Injection force stable output control mechanism and automatic injection pen

Abstract

The utility model discloses an injection force stable output control mechanism and an automatic injection pen, and relates to the technical field of medical instruments, an injection assembly and an adjusting assembly of the injection force stable output control mechanism are respectively provided with a pin shaft and a slideway; the supporting assembly and the adjusting assembly are provided with a joint structure and a gear structure respectively. When the injection assembly moves, the injection assembly drives the adjusting assembly to move, the adjusting assembly rotates to be separated from the joint position, then the second elastic piece drives the adjusting assembly to move, and the adjusting assembly rotates to the joint position again after moving towards the injection assembly. The same-direction movement of the pushing and injecting assembly and the adjusting assembly is achieved through the repeated process, the lengths of the first elastic pieces driving the pushing and injecting assembly at different axial positions are the same, and the stability of output elastic force is achieved. According to the injection force stable output control mechanism, the problem that the injection force of a traditional automatic injection pen is unstable due to the change of the elastic force of a spring is solved, stable output of liquid medicine in the injection process is achieved, and the injection accuracy and the use experience of a patient are improved.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a push force stable output control mechanism and an automatic injection pen. Background Art

[0002] An autoinjector pen is a portable drug delivery device used in the medical field that enables patients to self-administer medication injections. A key component of this device is its release mechanism, which initially locks the plunger and unlocks it when triggered by the user, pushing the medication through the needle and accurately injecting it into the patient's body.

[0003] While autoinjectors offer convenience to patients, existing technologies still have limitations. Traditional autoinjectors rely on spring force to inject medication, which makes it difficult to maintain a constant injection force. As the spring deforms during compression and release, its force fluctuates, leading to unstable injection force and uneven injection speed, impacting the effectiveness of the injection. Utility Model Content

[0004] The purpose of this application is to provide a stable injection force output control mechanism that solves the problem of unstable injection force caused by spring elasticity fluctuations in traditional automatic injection pens, achieving stable output during the injection process of liquid medicine, improving injection accuracy and patient experience. Another purpose of this application is to provide an automatic injection pen.

[0005] To achieve the above objectives, the present application provides a push force stable output control mechanism, comprising:

[0006] Support components;

[0007] a push assembly, disposed on the support assembly, and capable of axially moving relative to the support assembly;

[0008] An adjusting assembly is provided on the supporting assembly, and the adjusting assembly can move axially and rotate circumferentially relative to the supporting assembly;

[0009] A first elastic member is provided between the push injection assembly and the adjustment assembly, and the first elastic member is used to drive the push injection assembly to move in a direction away from the adjustment assembly, so that the push injection of the liquid medicine is achieved through the movement of the push injection assembly;

[0010] One of the push assembly and the adjustment assembly is provided with a slideway, and the other is provided with a pin, and the pin cooperates with the slideway to achieve axial movement and circumferential rotation of the adjustment assembly;

[0011] One of the support assembly and the adjustment assembly is provided with a step structure distributed along the axial direction, and the other is provided with a coupling structure, wherein the coupling structure cooperates with the step structure to limit the axial movement of the adjustment assembly;

[0012] A second elastic member is provided between the supporting assembly and the adjusting assembly;

[0013] When the adjusting assembly rotates to the engagement position, the engagement structure cooperates with the gear structure to limit the movement of the adjusting assembly; when the injection assembly moves, the injection assembly first drives the adjusting assembly to move, the adjusting assembly rotates out of the engagement position, and then the second elastic member drives the adjusting assembly to move, and the adjusting assembly moves toward the injection assembly and rotates to the engagement position again; the process is repeated to achieve the same-direction movement of the injection assembly and the adjusting assembly, so that the first elastic member has the same length at different axial positions, thereby achieving stable output elastic force.

[0014] In some embodiments, the adjustment assembly includes a pressure cylinder located inside the support assembly.

[0015] In some embodiments, the support assembly includes a sleeve, which is sleeved on the outside of the pressure cylinder.

[0016] In some embodiments, the first end of the sleeve is through and the second end of the sleeve is closed; the second elastic member is located inside the supporting assembly, and the second elastic member is connected to or abuts the inner side of the second end of the sleeve and the pressure cylinder.

[0017] In some embodiments, the first end of the pressure cylinder is closed and the second end of the pressure cylinder is through; the second elastic member is connected to or abuts the inner side of the first end of the pressure cylinder; the first elastic member is connected to or abuts the outer side of the first end of the pressure cylinder and the injection assembly.

[0018] In some embodiments, the injection assembly includes a push rod and an adjustment cylinder connected to each other, the push rod is sleeved on the outside of the sleeve, and the adjustment cylinder is sleeved on the outside of the pressure cylinder.

[0019] In some embodiments, the push rod is sleeved on the outside of the adjustment cylinder, and the push rod is snap-connected to the adjustment cylinder.

[0020] In some embodiments, the first end and the second end of the adjusting cylinder are connected; the injection force stable output control mechanism also includes an adjusting member, which is arranged at the first end of the adjusting cylinder, and the axial position of the adjusting member is adjustable; the first elastic member is connected to or abuts the adjusting member on the inner side of the first end of the adjusting cylinder.

[0021] In some embodiments, the support assembly includes a sleeve, the injection assembly includes a push rod and an adjustment cylinder, the adjustment assembly includes a pressure cylinder, and the injection force stable output control mechanism further includes an adjustment member;

[0022] The slideway is arranged inside the adjustment cylinder, and the pin is arranged outside the pressure cylinder; and / or,

[0023] The step structure is provided inside the sleeve, and the engagement structure is provided outside the pressure cylinder; and / or,

[0024] The first elastic member and / or the second elastic member is a spring; and / or,

[0025] The gear structure and / or the engagement structure is a rack; and / or,

[0026] The adjusting member is threadedly connected to the adjusting cylinder.

[0027] The present application also provides an automatic injection pen, comprising the above-mentioned injection force stable output control mechanism.

[0028] With respect to the above-mentioned background technology, the push force stable output control mechanism provided by the present application mainly includes a supporting component, a push component and an adjusting component. The push component is arranged on the supporting component, and the push component can move axially relative to the supporting component; the adjusting component is arranged on the supporting component, and the adjusting component can move axially and rotate circumferentially relative to the supporting component; a first elastic member is provided between the push component and the adjusting component, and the first elastic member is used to drive the push component to move in a direction away from the adjusting component, and the push of the liquid medicine is achieved by the movement of the push component; one of the push component and the adjusting component is provided with a slide, and the other is provided with a pin, and the pin cooperates with the slide to achieve axial movement and circumferential rotation of the adjusting component; the support component and the adjusting component are provided with a first elastic member. One of them is provided with a step structure distributed along the axial direction, and the other is provided with a coupling structure, and the coupling structure cooperates with the step structure to limit the axial movement of the adjusting component; a second elastic member is provided between the supporting component and the adjusting component; when the adjusting component rotates to the coupling position, the coupling structure cooperates with the step structure to limit the movement of the adjusting component; when the injection component moves, the injection component first drives the adjusting component to move, and the adjusting component rotates out of the coupling position, and then the second elastic member drives the adjusting component to move, and the adjusting component moves toward the injection component and rotates to the coupling position again; the process is repeated to realize the same-direction movement of the injection component and the adjusting component, so that the length of the first elastic member is the same at different axial positions, thereby realizing the stability of the output elastic force.

[0029] In traditional autoinjector pens, the spring force varies with its length, leading to unstable injection force. This instability can cause uneven injection speeds during the injection process, affecting accurate drug delivery and even causing pain to the patient, reducing injection accuracy and user experience.

[0030] To address this issue, the present invention provides a stable injection force output control mechanism that employs a series of innovative designs to ensure injection force stability. First, the mechanism comprises a support assembly, a push assembly, and an adjustment assembly. The push assembly is capable of axial movement relative to the support assembly, while the adjustment assembly is capable of both axial movement and circumferential rotation, increasing the mechanism's flexibility.

[0031] A first elastic member is positioned between the push assembly and the adjustment assembly, pushing the push assembly away from the adjustment assembly to facilitate injection of the medication solution. The slideway and pin design between the push assembly and the adjustment assembly allow the adjustment assembly to move axially and rotate circumferentially. Furthermore, a step structure and a joint structure are positioned between the support assembly and the adjustment assembly. These structures work together to limit axial movement of the adjustment assembly, ensuring that it can stably limit the push force when in a specific position.

[0032] The second elastic member is the key to making the adjustment component adapt to the movement of the push assembly, and then adapt to the change in the length of the first elastic member. When the adjustment component rotates to the engagement position, the cooperation of the engagement structure and the gear structure can limit the movement of the adjustment component, thereby ensuring that the length of the first elastic member is the same at different axial positions, and achieving stable output elastic force. When the push assembly moves, it will drive the adjustment component to move, causing the adjustment component to rotate out of the engagement position, and then the second elastic member will drive the adjustment component to move toward the push assembly and rotate to the engagement position again. At this time, the length of the first elastic member between the push assembly and the adjustment component is restored to its original state. This process is repeated to achieve the same-direction movement of the push assembly and the adjustment assembly, maintain the constant length of the first elastic member, and ensure the stable output of the push force.

[0033] Combined with the above structure and process description, it can be seen that the injection force stable output control mechanism has at least the following beneficial effects: the injection force stable output control mechanism solves the problem of unstable injection force caused by changes in spring elastic force in traditional automatic injection pens, realizes stable output during the injection of drug solution, and improves the accuracy of injection and the patient's usage experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0035] Figure 1 A schematic diagram of a push force stable output control mechanism provided in an embodiment of the present application;

[0036] Figure 2 A cross-sectional view of a push force stable output control mechanism provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a sleeve provided in an embodiment of the present application;

[0038] Figure 4 A cross-sectional view of a sleeve provided in an embodiment of the present application;

[0039] Figure 5 A schematic diagram of a push rod provided in an embodiment of the present application;

[0040] Figure 6 A cross-sectional view of a push rod provided in an embodiment of the present application;

[0041] Figure 7 A schematic diagram of an adjustment cylinder provided in an embodiment of the present application;

[0042] Figure 8 A cross-sectional view of an adjustment cylinder provided in an embodiment of the present application;

[0043] Figure 9 A schematic diagram of a pressure cylinder provided in an embodiment of the present application;

[0044] Figure 10 A partial diagram of a pressure cylinder provided in an embodiment of the present application;

[0045] Figure 11 A schematic diagram of an adjusting member provided in an embodiment of the present application;

[0046] Figure 12 A comparison chart of the experimental effects of the injection force stable output control mechanism provided in the embodiments of the present application.

[0047] in:

[0048] Support component 100, sleeve 1, level structure 11, limiting rib 12,

[0049] Injection assembly 200, push rod 2, clamping hole 21, limiting groove 22, adjusting cylinder 3, slide 31, protrusion 32, internal thread 33,

[0050] Adjustment assembly 300, pressure cylinder 4, pin 41, joint structure 42,

[0051] The first elastic member 5,

[0052] The second elastic member 6,

[0053] Adjusting member 7, external thread 71. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0055] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0056] Please refer to Figure 1 and Figure 2 ,in, Figure 1 This is a schematic diagram of the injection force stable output control mechanism provided in an embodiment of the present application. Figure 2 A cross-sectional view of the injection force stabilization output control mechanism provided in an embodiment of the present application.

[0057] In a first specific embodiment, Figure 1 and Figure 2 As shown, the injection force stable output control mechanism provided by the embodiment of the present application mainly includes a support component 100, a push component 200 and an adjustment component 300.

[0058] The push assembly 200 is provided on the support assembly 100 and can move axially relative to the support assembly 100 ; the adjustment assembly 300 is provided on the support assembly 100 and can move axially and rotate circumferentially relative to the support assembly 100 .

[0059] A first elastic member 5 is provided between the push assembly 200 and the adjustment assembly 300. The first elastic member 5 applies a force to the push assembly 200 and the adjustment assembly 300. When the adjustment assembly 300 is the support point, the first elastic member 5 is used to drive the push assembly 200 to move in a direction away from the adjustment assembly 300, thereby achieving push injection of the medicinal solution through the movement of the push assembly 200.

[0060] One of the push assembly 200 and the adjustment assembly 300 is provided with a slideway 31 , and the other is provided with a pin 41 . The pin 41 cooperates with the slideway 31 to achieve axial movement and circumferential rotation of the adjustment assembly 300 .

[0061] One of the supporting assembly 100 and the adjusting assembly 300 is provided with an axially distributed gear structure 11 , and the other is provided with a coupling structure 42 . The coupling structure 42 cooperates with the gear structure 11 to limit the axial movement of the adjusting assembly 300 .

[0062] A second elastic member 6 is provided between the supporting assembly 100 and the adjusting assembly 300. The second elastic member 6 applies a force to the supporting assembly 100 and the adjusting assembly 300. When the supporting assembly 100 is the supporting point and the movement of the adjusting assembly 300 is not restricted, the second elastic member 6 drives the adjusting assembly 300 to move.

[0063] Before the push force stable output control mechanism is used, the positions of the various components are fixed in the initial state, especially when the adjustment component 300 is rotated to the engagement position, the engagement structure 42 cooperates with the gear structure 11 to limit the movement of the adjustment component 300. At this time, the axial position of the adjustment component 300 is fixed at this specific circumferential angle; when the push force stable output control mechanism is used, it is switched from the initial state to the trigger state, and the push component 200 is no longer restricted (the prior restriction of the push component 200 can be achieved by a structure other than the push force stable output control mechanism, which is not within the scope of the description of this embodiment). In particular, when the push component 200 moves, due to the cooperation relationship between the pin 41 and the slide 31, the push component 200 first drives the adjustment component 300 to move, and the adjustment component 300 then moves. 00 rotates out of the engagement position 42, at which point the adjustment component 300 leaves the specific circumferential angle that keeps the axial position fixed, and the second elastic member 6 drives the adjustment component 300 to move. At this point, the adjustment component 300 simultaneously performs axial movement and circumferential rotation, so that the adjustment component 300 moves toward the injection component 200 and then rotates to the engagement position 42. At this point, the axial position of the adjustment component 300 remains fixed at this specific circumferential angle, but the axial position of the adjustment component 300 at this time has moved toward the injection component 200 compared to the axial position of the adjustment component 300 before this movement; the repeated process realizes the same-directional movement of the injection component 200 and the adjustment component 300, so that the first elastic member 5 has the same length at different axial positions, thereby achieving stable output elastic force.

[0064] In traditional autoinjector pens, the spring force varies with its length, leading to unstable injection force. This instability can cause uneven injection speeds during the injection process, affecting accurate drug delivery and even causing pain to the patient, reducing injection accuracy and user experience.

[0065] To address this issue, the present invention provides a stable injection force output control mechanism that employs a series of innovative designs to ensure injection force stability. First, the mechanism comprises a support assembly 100, a push assembly 200, and an adjustment assembly 300. The push assembly 200 is capable of axial movement relative to the support assembly 100, while the adjustment assembly 300 is capable of both axial movement and circumferential rotation, increasing the mechanism's flexibility.

[0066] A first elastic member 5 is positioned between the push assembly 200 and the adjustment assembly 300, pushing the push assembly 200 away from the adjustment assembly 300 to facilitate injection of the medication. The slideway 31 and pin 41, designed to coordinate between the push assembly 200 and the adjustment assembly 300, enable axial movement and circumferential rotation of the adjustment assembly 300. Furthermore, a step structure 11 and an engagement structure 42 are positioned between the support assembly 100 and the adjustment assembly 300. These structures, in concert, limit axial movement of the adjustment assembly 300, ensuring stable control of the push force when in a specific position.

[0067] The second elastic member 6 is the key to making the adjustment component 300 adapt to the movement of the injection component 200, and then adapt to the change in the length of the first elastic member 5. When the adjustment component 300 rotates to the engagement position, the cooperation between the engagement structure 42 and the gear structure 11 can limit the movement of the adjustment component 300, thereby ensuring that the length of the first elastic member 5 at different axial positions is the same, and achieving stable output elastic force. When the injection component 200 moves, it will drive the adjustment component 300 to move, causing the adjustment component 300 to rotate out of the engagement position 42, and then the second elastic member 6 will drive the adjustment component 300 to move toward the injection component 200 and rotate to the engagement position 42 again. At this time, the length of the first elastic member 5 between the injection component 200 and the adjustment component 300 is restored to its original state. This process is repeated to achieve the same-direction movement of the injection component 200 and the adjustment component 300, maintain the constant length of the first elastic member 5, and ensure the stable output of the injection force.

[0068] Combined with the above structure and process description, it can be seen that the injection force stable output control mechanism has at least the following beneficial effects: the injection force stable output control mechanism solves the problem of unstable injection force caused by changes in spring elastic force in traditional automatic injection pens, realizes stable output during the injection of drug solution, and improves the accuracy of injection and the patient's usage experience.

[0069] In some cases, the slide 31 is provided in the injection assembly 200 , and the pin 41 is provided in the adjustment assembly 300 ; the step structure 11 is provided in the support assembly 100 , and the coupling structure 42 is provided in the adjustment assembly 300 .

[0070] In some cases, the support assembly 100 includes a sleeve 1 ; the push assembly 200 includes a push rod 2 and an adjustment cylinder 3 ; and the adjustment assembly 300 includes a pressure cylinder 4 .

[0071] In some cases, the slideway 31 is provided on the regulating cylinder 3 , and the pin shaft 41 is provided on the pressure cylinder 4 ; the step structure 11 is provided on the sleeve 1 , and the engaging structure 42 is provided on the pressure cylinder 4 .

[0072] Please refer to Figure 3 and Figure 4 , Figure 3 A schematic diagram of a sleeve provided in an embodiment of the present application, Figure 4 A cross-sectional view of a sleeve provided in an embodiment of the present application.

[0073] like Figure 3 and Figure 4 As shown, in some embodiments, the support assembly 100 includes a sleeve 1 , the step structure 11 is disposed inside the sleeve 1 , and the limiting rib 12 is disposed outside the sleeve 1 .

[0074] The step structures 11 and the limiting ribs 12 can be arranged in two groups symmetrically in the circumferential direction of the sleeve 1 .

[0075] Please refer to Figure 5 and Figure 6 , Figure 5 A schematic diagram of a push rod provided in an embodiment of the present application, Figure 6 A cross-sectional view of a push rod provided in an embodiment of the present application.

[0076] like Figure 5 and Figure 6 As shown, in some embodiments, the injection assembly 200 includes a push rod 2, which is provided with a clamping hole 21 and a limiting groove 22. The limiting groove 22 is located inside the push rod 2. Through the cooperation between the limiting groove 22 and the limiting rib 12, the axial movement and circumferential fixation of the sleeve 1 relative to the push rod 2 are achieved.

[0077] The locking holes 21 and the limiting grooves 22 can be arranged in two groups symmetrically in the circumferential direction of the push rod 2 .

[0078] Please refer to Figure 7 and Figure 8 , Figure 7 This is a schematic diagram of the adjustment cylinder provided in an embodiment of the present application. Figure 8 A cross-sectional view of the adjustment cylinder provided in an embodiment of the present application.

[0079] like Figure 7 and Figure 8 As shown, in some embodiments, the injection assembly 200 includes an adjusting cylinder 3 , which is provided with a slide 31 , a protrusion 32 and an internal thread 33 . The slide 31 and the internal thread 33 are located inside the adjusting cylinder 3 , and the protrusion 32 is located outside the adjusting cylinder 3 .

[0080] The slideways 31 and the protrusions 32 may be arranged in two groups symmetrically in the circumferential direction of the adjusting cylinder 3 .

[0081] Please refer to Figure 9 and Figure 10 , Figure 9 This is a schematic diagram of a pressure cylinder provided in an embodiment of the present application. Figure 10 A partial view of the pressure cylinder provided in an embodiment of the present application.

[0082] like Figure 9 and Figure 10 As shown, in some embodiments, the adjustment assembly 300 includes a pressure cylinder 4 , and a pin 41 and a coupling structure 42 are disposed outside the pressure cylinder 4 .

[0083] The pins 41 and the coupling structures 42 may be arranged in two groups symmetrically in the circumferential direction of the pressure cylinder 41 .

[0084] In some embodiments, the adjustment assembly 300 includes a pressure cylinder 4 , which is located inside the support assembly 100 .

[0085] In this embodiment, this arrangement allows the pressure cylinder 4 to interact effectively with other components under the protection of the support assembly 100. The support assembly 100 not only provides physical support for the pressure cylinder 4, but also helps to organize the spatial layout within the mechanism, ensuring proper alignment and functional coordination between the various components.

[0086] In some embodiments, the support assembly 100 includes a sleeve 1 , which is sleeved on the outside of the pressure cylinder 4 .

[0087] In this embodiment, this design allows the sleeve 1 to protect and position the pressure barrel 4. By fitting the sleeve 1 over the pressure barrel 4, the structural stability and positioning accuracy of the pressure barrel 4 within the autoinjector pen are ensured. This configuration helps maintain the structural integrity of the entire injection force output control mechanism while also facilitating assembly and maintenance.

[0088] In some embodiments, the first end of the sleeve 1 is through and the second end of the sleeve 1 is closed; the second elastic member 6 is located inside the support assembly 100, and the second elastic member 6 is connected or abutted to the inner side of the second end of the sleeve 1 and the pressure cylinder 4.

[0089] In this embodiment, the design of the sleeve 1 features a through-hole at the first end and a closed second end. This structural design helps achieve specific functional requirements. The through-hole first end allows other components to pass through the sleeve 1 smoothly, while the closed second end provides a stable support point for the components inside the sleeve 1.

[0090] The second elastic member 6 is located within the support assembly 100 and is connected to or abuts the inner side of the second end of the sleeve 1 and the pressure cylinder 4. This arrangement enables the second elastic member 6 to effectively exert a force on the pressure cylinder 4, thereby fulfilling its function during operation of the autoinjector pen. The second elastic member 6 not only provides the necessary elastic force but also plays a role in regulating the interaction between the push assembly 200 and the adjustment assembly 300.

[0091] In some embodiments, the first end of the pressure cylinder 4 is closed and the second end of the pressure cylinder 4 is through; the second elastic member 6 is connected or abutted to the inner side of the first end of the pressure cylinder 4; the first elastic member 5 is connected or abutted to the outer side of the first end of the pressure cylinder 4 and the injection assembly 200.

[0092] In this embodiment, the design of the pressure cylinder 4 has the characteristics of being closed at the first end and being connected at the second end. Such a structural design allows the first end of the pressure cylinder 4 to serve as an effective fixing point, while the connected second end allows other components to pass through smoothly, thereby facilitating assembly and function realization.

[0093] The second elastic member 6 is connected to or abuts against the inner side of the first end of the pressure cylinder 4 . This configuration enables the second elastic member 6 to directly apply a force to the pressure cylinder 4 .

[0094] At the same time, the first elastic member 5 is connected to or abuts the outer side of the first end of the pressure cylinder 4 and the injection assembly 200. This arrangement allows the first elastic member 5 to play a key role in the injection process. The first elastic member 5 is responsible for providing the injection force, ensuring that the liquid medicine can be pushed out with a stable force.

[0095] In some embodiments, the injection assembly 200 includes a push rod 2 and an adjustment cylinder 3 connected to each other. The push rod 2 is sleeved on the outside of the sleeve 1, and the adjustment cylinder 3 is sleeved on the outside of the pressure cylinder 4.

[0096] In this embodiment, the push rod assembly 200 consists of a push rod 2 and an adjustment cylinder 3, which are respectively mounted on the outside of the sleeve 1 and the pressure cylinder 4, forming a compact and stable spatial layout. This layout not only reduces the overall volume of the structure, but also enhances its stability through the tight fit between the components, reducing vibration and displacement during use of the autoinjector pen. Furthermore, this design allows for precise control of the push force, ensuring that the drug solution is injected evenly and accurately. Furthermore, the external mounting of the components simplifies the assembly and maintenance of the autoinjector pen, improving its ease of maintenance.

[0097] In some embodiments, the push rod 2 is sleeved on the outside of the adjustment cylinder 3 , and the push rod 2 is snap-connected to the adjustment cylinder 3 .

[0098] In this embodiment, this design allows the push rod 2 to be securely positioned on the adjustment barrel 3 while allowing for quick disassembly and assembly when needed. The snap-fit ​​connection provides a simple and effective securing method, ensuring the stability and reliability of the push rod 2 during the injection process. Furthermore, this connection method simplifies production and maintenance, as the snap-fit ​​structure is easy to operate, helping to improve the assembly efficiency and maintenance convenience of the entire autoinjector pen.

[0099] Specifically, the snap connection between the push rod 2 and the adjusting cylinder 3 is achieved by the cooperation between the snap hole 21 and the protrusion 32 .

[0100] Please refer to Figure 11 , Figure 11 A schematic diagram of an adjusting member provided in an embodiment of the present application.

[0101] In some embodiments, the first end and the second end of the adjusting cylinder 3 are connected; the injection force stable output control mechanism also includes an adjusting member 7, which is arranged at the first end of the adjusting cylinder 3, and the axial position of the adjusting member 7 is adjustable; the first elastic member 5 is connected or abutted with the adjusting member 7 on the inner side of the first end of the adjusting cylinder 3.

[0102] In this embodiment, the adjustment tube 3 is designed to be through-hole at both ends. This structure allows for effective interaction between the internal adjustment member 7 and the first elastic member 5. The adjustment member 7 is located at the first end of the adjustment tube 3, and its axial position can be adjusted as needed. The key advantage of this design is that it provides a mechanism to change the length, or compression, of the first elastic member 5 by varying the position of the adjustment member 7, thereby adjusting the injection force generated.

[0103] This adjustment mechanism allows the autoinjector pen to adapt to different drug viscosities and injection depth requirements, ensuring the accuracy and consistency of the injection process. By adjusting the compression of the first elastic member 5, the injection speed and force of the drug can be precisely controlled, thereby optimizing the injection effect and reducing patient discomfort.

[0104] In some embodiments, the adjusting member 7 is threadedly connected to the adjusting cylinder 3 .

[0105] In this embodiment, this threaded connection not only provides a reliable fixing method, but also allows the adjusting member 7 to be precisely adjusted along the axial direction of the adjusting barrel 3. By rotating the adjusting member 7, its position on the adjusting barrel 3 can be changed, thereby changing the tension of the first elastic member 5, thereby achieving precise control of the injection force.

[0106] The advantages of a threaded connection lie in its reversibility and repeatability, meaning it can be easily adjusted to the optimal position, and the same adjustment can be repeated as needed without compromising the stability of the connection. Furthermore, the threaded connection provides a certain degree of self-locking, preventing accidental movement of the adjustment member 7 during use, ensuring stability and safety during the injection process. This design makes the autoinjector pen more flexible and adaptable, enabling it to meet the specific needs of different patients.

[0107] Specifically, the threaded connection between the adjusting member 7 and the adjusting cylinder 3 is achieved by the cooperation between the internal thread 33 on the adjusting cylinder 3 and the external thread 71 on the adjusting member 7 .

[0108] In some embodiments, the first elastic member 5 and / or the second elastic member 6 is a spring. In addition, the first elastic member 5 and / or the second elastic member 6 may also adopt other elastic structures, which should also fall within the scope of the description of this application.

[0109] In some embodiments, the step structure 11 and / or the engaging structure 42 is a rack. In addition, the step structure 11 and / or the engaging structure 42 may also adopt other snap-fit ​​structures, which should also fall within the scope of the description of this application.

[0110] Please continue to refer to Figures 1 to 11 In a specific embodiment, the slideway 31 is provided inside the regulating cylinder 3, and the pin 41 is provided outside the pressure cylinder 4. The gear structure 11 is provided inside the sleeve 1, and the engaging structure 42 is provided outside the pressure cylinder 4.

[0111] The present application discloses a spring elastic force stable output control mechanism, namely a push force stable output control mechanism, which can achieve stable output of the elastic force of the first elastic member 5, and the stable output elastic force can be adjusted. Unlike conventional spring elastic force which is output in a proportional linear manner, this mechanism can output stably under a specific elastic force, and can maintain force stability even when the elastic force changes from a high compression amount to a low compression amount. The spring elastic force stable output control mechanism is mainly composed of a support component 100, a push component 200, and an adjustment component 300, wherein the support component 100 includes a sleeve 1, the push component 200 includes a push rod 2 and an adjustment cylinder 3, and the adjustment component 300 includes a pressure cylinder 4. The magnitude of the spring output force is adjusted by the adjustment member 7.

[0112] Taking the first end as the front end or lower end near the injection site and the second end as the rear end or upper end away from the front end as an example, the innermost portion of the mechanism, from the inside out, is the second elastic member 6. The second elastic member 6 is housed within the pressure tube 4, with its exposed end resting on the bottom of the sleeve 1. The pressure tube 4 can move downward with the release of the second elastic member 6, but the engagement structure 42 and the step structure 11 engage to restrict the release of the second elastic member 6. The pin 41 moves within the slide 31, causing the pressure tube 3 to rotate counterclockwise as the adjustment tube 3 moves downward. The protrusion 32 engages with the retaining hole 21, securing the adjustment tube 3 relative to the push rod 2. The external thread 71 is used to assemble the adjustment member 7, pressing against the first elastic member 5. Rotating the adjustment member 7 adjusts the outward release force of the entire mechanism. One end of the first elastic member 5 rests on the adjustment member 7, and the other end rests on the pressure tube 4. The second elastic member 6 is formed by the interlocking pressure tube 4 and sleeve 1. The two ends of the second elastic member 6 press against the bottoms of the pressure tube 4 and sleeve 1, respectively. When the pressure is released, the two separate. During operation, the unopened end of the sleeve 1 is fixed, serving as the support point for the entire mechanism. One end of the push rod 2, which is also the end where the adjustment tube 3 is assembled, acts as the release force, pushing outward. Inward rotation of the adjustment member 7 increases the outward release force of the entire mechanism, while outward rotation reduces the release force.

[0113] The function of this device requires the following two prerequisites: the pressure of the second elastic member 6 at its minimum compression (the amount of compression of the second elastic member 6 when the entire mechanism is fully operational) must be greater than the pressure set by the first elastic member 5; and the force exerted by the push rod 2 to push an object, such as a piston, must be less than the elastic force set by the first elastic member 5. Both of these conditions can be met at the outset of the design.

[0114] The first elastic member 5 is regarded as an adjustment spring, the second elastic member 6 is regarded as a pressure spring, the gear structure 11 and the engagement structure 42 are regarded as racks, and it is assumed that this device is used in an automatic injection pen, as described below.

[0115] The initial state is a restricted state, that is, the engaging structure 42 (rack) on the pressure cylinder 4 and the gear structure 11 (rack) on the regulating cylinder 3 are engaged with each other, and the second elastic member 6 (pressure spring) is restricted from exerting force on the push rod 2. At this time, the first elastic member 5 (regulating spring) is not restricted and can exert force externally. When the first elastic member 5 releases the force outward, it pushes the regulating member 7, regulating cylinder 3, and push rod 2 downward, thereby pushing the piston in the prefilled syringe to move. Assuming that the elastic force of the first elastic member 5 before movement is 8N, the elastic force gradually decreases as the force is released; the regulating cylinder 3, push rod 2, and sleeve 1 are circumferentially fixed to each other. When the first elastic member 5 drives the regulating cylinder 3 to move downward, the interaction between the slideway 31 of the regulating cylinder 3 and the pin 41 of the pressure cylinder 4 drives the pressure cylinder 4 to rotate clockwise. After the regulating cylinder 3 moves downward a certain distance, the pressure of the first elastic member 5 is 7.5N, and the engaging structure 42 on the pressure cylinder 4 and the gear structure 11 (rack) on the pressure cylinder 4 are engaged with each other. The step structures 11 inside the sleeve 1 are separated from each other. At this time, the second elastic member 6 is no longer restricted and begins to release force outward. Because the push rod 2 moves relatively slowly under the action of the piston resistance, the pressure cylinder 4 moves at a speed greater than the downward movement speed of the push rod 2 under the action of the second elastic member 6. The adjusting cylinder 3 drives the pressure cylinder 4 to rotate counterclockwise, and the engaging structure 42 on the pressure cylinder 4 and the step structure 11 inside the sleeve 1 are engaged with each other again. The second elastic member 6 is restricted again. At this time, the first elastic member 5 continues to release force outward, pushing the adjusting member 7, the adjusting cylinder 3, and the push rod 2 to move downward, and the elastic force of the first elastic member 5 is restored to 8N. This cycle is repeated reciprocally to achieve the function of this mechanism to output stable force.

[0116] To adjust the output force of the mechanism, the adjusting member 7 is adjusted to adjust the outward output force of the entire mechanism. Rotating the adjusting member 7 inward compresses the first elastic member 5. Because the elastic force of the second elastic member 6 is always greater than that of the first elastic member 5, the pressure cylinder 4 does not move upward when the first elastic member 5 is compressed. This process is repeated to achieve a change in the output force.

[0117] Please refer to Figure 12 , Figure 12 A comparison chart of the experimental effects of the injection force stable output control mechanism provided in the embodiments of the present application.

[0118] Figure 12 In the figure, line ① is the elastic effect of the second elastic member 6, line ② is the elastic effect of the first elastic member 5 after adjustment by the adjusting member 7, and line ③ is the elastic effect of the first elastic member 5 before adjustment by the adjusting member 7.

[0119] The spring force stable output control mechanism of the present application has many advantages: First, it can stably output the spring force, ensure the stability during the drug injection process, and avoid injection speed fluctuations caused by changes in spring force. Secondly, the adjustment mechanism equipped with this mechanism allows the output force to be adjusted, which not only helps to reduce the pain of the patient during injection, but also can adjust the injection speed according to the needs of different drugs. In addition, this design also significantly reduces the time for new product development because it supports the use of the same components for different drugs, thereby improving the versatility and production efficiency of the product. In general, this control mechanism plays an important role in improving the performance and user experience of the injection pen.

[0120] This application also provides an autoinjector pen, including the aforementioned injection force stabilization output control mechanism. The autoinjector pen also includes other mechanisms, such as a mechanism for locking and unlocking the push rod 2. The autoinjector pen can be installed with a prefilled syringe, which has a piston. When the autoinjector pen is unlocked, the push rod 2 pushes the piston, pushing the liquid in the prefilled syringe out.

[0121] The automatic injection pen should have all the beneficial technical effects of the above-mentioned injection force stable output control mechanism, which will not be described in detail here.

[0122] It should be noted that many of the components mentioned in this application are universal standard parts or components known to those skilled in the art, and their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0123] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0124] The above is a detailed introduction to the injection force stable output control mechanism and automatic injection pen provided by this application. Specific examples are used herein to illustrate the principles and implementation methods of this application. The description of the above embodiments is only intended to help understand the method and core concept of this application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of this application, several improvements and modifications can be made to this application, and these improvements and modifications also fall within the scope of protection of the claims of this application.

Claims

1. A push force stable output control mechanism, characterized in that: include: Support components; a push assembly, disposed on the support assembly, and capable of axially moving relative to the support assembly; An adjusting assembly is provided on the supporting assembly, and the adjusting assembly can move axially and rotate circumferentially relative to the supporting assembly; A first elastic member is provided between the push injection assembly and the adjustment assembly, and the first elastic member is used to drive the push injection assembly to move in a direction away from the adjustment assembly, so that the push injection of the liquid medicine is achieved through the movement of the push injection assembly; One of the push assembly and the adjustment assembly is provided with a slideway, and the other is provided with a pin, and the pin cooperates with the slideway to achieve axial movement and circumferential rotation of the adjustment assembly; One of the support assembly and the adjustment assembly is provided with a step structure distributed along the axial direction, and the other is provided with a coupling structure, wherein the coupling structure cooperates with the step structure to limit the axial movement of the adjustment assembly; A second elastic member is provided between the supporting assembly and the adjusting assembly; When the adjusting assembly rotates to the engagement position, the engagement structure cooperates with the gear structure to limit the movement of the adjusting assembly; when the injection assembly moves, the injection assembly first drives the adjusting assembly to move, the adjusting assembly rotates out of the engagement position, and then the second elastic member drives the adjusting assembly to move, and the adjusting assembly moves toward the injection assembly and rotates to the engagement position again; the process is repeated to achieve the same-direction movement of the injection assembly and the adjusting assembly, so that the first elastic member has the same length at different axial positions, thereby achieving stable output elastic force.

2. The injection force stable output control mechanism according to claim 1, characterized in that: The adjustment assembly includes a pressure cylinder, which is located inside the supporting assembly.

3. The injection force stable output control mechanism according to claim 2, characterized in that: The supporting component includes a sleeve, and the sleeve is sleeved on the outside of the pressure cylinder.

4. The injection force stable output control mechanism according to claim 3, characterized in that: The first end of the sleeve is through, and the second end of the sleeve is closed; the second elastic member is located inside the supporting assembly, and the second elastic member is connected to or abuts against the inner side of the second end of the sleeve and the pressure cylinder.

5. The injection force stable output control mechanism according to claim 4, characterized in that: The first end of the pressure cylinder is closed, and the second end of the pressure cylinder is through; the second elastic member is connected to or abuts the inner side of the first end of the pressure cylinder; the first elastic member is connected to or abuts the outer side of the first end of the pressure cylinder and the injection assembly.

6. The injection force stable output control mechanism according to claim 3, characterized in that: The push injection assembly includes a push rod and an adjustment cylinder connected to each other. The push rod is sleeved on the outside of the sleeve, and the adjustment cylinder is sleeved on the outside of the pressure cylinder.

7. The injection force stable output control mechanism according to claim 6, characterized in that: The push rod is sleeved on the outside of the adjusting cylinder, and the push rod is buckled and connected to the adjusting cylinder.

8. The injection force stable output control mechanism according to claim 6, characterized in that: The first end and the second end of the adjusting cylinder are connected; the injection force stable output control mechanism also includes an adjusting member, which is arranged at the first end of the adjusting cylinder and the axial position of the adjusting member is adjustable; the first elastic member is connected to or abuts against the adjusting member on the inner side of the first end of the adjusting cylinder.

9. The injection force stable output control mechanism according to any one of claims 1 to 8, characterized in that: The support assembly includes a sleeve, the push assembly includes a push rod and an adjustment cylinder, the adjustment assembly includes a pressure cylinder, and the push force stable output control mechanism also includes an adjustment member; The slideway is arranged inside the regulating cylinder, and the pin is arranged outside the pressure cylinder; and / or, The step structure is arranged inside the sleeve, and the engagement structure is arranged outside the pressure cylinder; and / or, The first elastic member and / or the second elastic member is a spring; and / or, The gear structure and / or the engagement structure is a rack; and / or, The adjusting member is threadedly connected to the adjusting cylinder.

10. An automatic injection pen, characterized in that: It includes the injection force stable output control mechanism as described in any one of claims 1 to 9.

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