Safety auto-injector
The safety-enhancing automated injection pen with a dual-confirmation mechanism solves the problem of unauthorized activation during transportation and storage, improving safety and operational flexibility, and preventing accidental triggering and needle prick injuries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGSU WANHAI MEDICAL INSTR CO LTD
- Filing Date
- 2025-12-19
- Publication Date
- 2026-07-21
Smart Images
Figure CN121371390B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of medical technology, specifically relating to syringes, and more particularly to a safety-type automatic injection pen. Background Technology
[0002] Automatic injection devices, especially those employing a two-step activation mechanism, are commonly used in routine treatments. These devices typically require the user to first press the injection tip against the injection site and then trigger the activation button to administer the medication.
[0003] However, these injection pens also face serious challenges during transportation and storage; that is, the injection pen is activated involuntarily; specifically, its activation mechanism, such as the needle cap, is easily triggered by accidental drops, squeezing, or improper operation, or by unintended users (such as children or unsuspecting others) accidentally touching the activation mechanism; this not only leads to waste of the medication, but may also cause needle prick injuries, affecting the overall safety of the injection pen.
[0004] Therefore, how to prevent the injection pen from being activated without authorization is a technical problem that urgently needs to be solved in this field.
[0005] It should be noted that the information disclosed in this background section is only for understanding the background technology of the present application concept, and therefore, the above description is not considered to constitute prior art information. Summary of the Invention
[0006] This disclosure provides at least one safe automated injection pen to address the technical problem of unauthorized activation of the injection pen.
[0007] This disclosure provides a safe automatic injection pen, including: a pen body sleeve, with a button at the distal end and a needle cover at the proximal end; An actuator is axially movable inside the pen body sleeve, with its distal end connected to the button and its proximal end having a protrusion. The excitation sleeve is axially movable and sleeved on the outer wall of the actuator. When the injection pen is not excited, the actuator is radially limited inside the excitation sleeve. A push rod, which is fitted inside the actuator; The outer wall of the push rod is provided with an annular groove, and the protrusion is stuck in the annular groove; a plunger rod spring is housed inside the push rod; When the needle sleeve presses against the injection site, the excitation sleeve moves a first displacement H1 relative to the actuator in the direction away from the needle. When the button is pressed, the actuator moves a second displacement H2 relative to the excitation sleeve in the direction of the needle. When both the first displacement H1 and the second displacement H2 occur, the protrusion separates from the annular groove to release the plunger rod spring, allowing the push rod to drive the rubber stopper to move towards the needle to complete the injection. The injection pen also includes: a needle cover spring, which is sleeved on the surface of the excitation sleeve. One end of the needle cover spring abuts against the outer wall protrusion ring of the excitation sleeve, and the other end is adapted to abut against the stop part. When the first displacement H1 or the second displacement H2 occurs, the needle cover spring is compressed. After the injection is completed, the needle cover is moved away from the injection site, and the needle cover spring drives the sleeve to move the needle cover towards the needle to cover the needle.
[0008] In one alternative embodiment, the injection pen further includes an intermediate component and a refill holder, with the intermediate component located axially between the actuator and the refill holder. When the button is pressed, the actuator causes the intermediate component and the refill holder to move together along the needle direction.
[0009] In one optional embodiment, the injection pen includes: a hook at one end of a middle component and a boss at the other end; a first limiter at the end of the pen refill holder adjacent to the middle component; the hook engaging in an annular groove; and the boss stopping the first limiter.
[0010] In one alternative embodiment, a second limit is provided at the end of the pen sleeve near the needle tip, and the actuator drives the intermediate part and the pen refill holder to move together along the needle tip direction until the pen refill holder stops at the second limit.
[0011] In one alternative embodiment, the other end of the actuator is provided with an elastic tongue in the direction away from the protrusion, and the inner wall of the actuating sleeve is provided with a first step; In the unactivated state, the elastic tongue of the injection pen is stuck in the first step.
[0012] In one alternative embodiment, the inner wall of the excitation sleeve is provided with a second step. After the injection is completed, the needle cover is displaced from the injection part, and the needle cover spring drives the excitation sleeve to move towards the needle, with the elastic tongue abutting against the second step.
[0013] In one optional embodiment, a third limit is provided on the pen body sleeve, which is located on the side of the second limit away from the needle tip. A fourth limit is provided on the needle tip cover. After injection, the needle tip cover is displaced from the injection site, and the needle tip cover spring drives the needle tip cover to move towards the needle tip until the third and fourth limits stop.
[0014] In one alternative embodiment, the push rod is provided with an annular boss, the push rod drives the rubber stopper to move towards the needle, and when the annular boss on the push rod slides past the hook, an injection completion prompt sound is emitted.
[0015] In one alternative embodiment, the boss of the intermediate component abuts against the end face of the medicine bottle, thereby limiting the axial movement of the medicine bottle.
[0016] The beneficial effect of this invention is that it provides a safe automatic injection pen. Through the coordinated action of components such as the button, actuator, activation sleeve, push rod, and needle cover on the pen body sleeve, it ensures that the injection process must undergo two independent confirmation actions before it can be triggered. When not activated, the protrusion of the actuator is stuck in the annular groove of the push rod, and the actuator is radially limited by the activation sleeve, thereby constraining the plunger rod spring and preventing it from being activated.
[0017] During activation, the needle sleeve presses against the injection site, and the activation sleeve moves a first displacement H1 relative to the actuator away from the needle. Then, pressing the button causes the actuator to move a second displacement H2 relative to the activation sleeve towards the needle. Only when both displacements H1 and H2 are successfully completed will the activation sleeve release the radial constraint on the actuator, causing the protrusion to disengage from the annular groove. The push rod is then driven by the plunger rod spring to complete the injection.
[0018] Thus, the dual confirmation mechanism effectively prevents accidental activation caused by a single unexpected action, such as accidentally pressing a button or applying pressure, greatly improving the safety of the injection pen.
[0019] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.
[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description
[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0022] Figure 1 A cross-sectional view of an injection pen provided in an embodiment of this disclosure; Figure 2 for Figure 1 Enlarged schematic diagram at point I; Figure 3 A perspective view of the button and brake provided in an embodiment of this disclosure; Figure 4 A cross-sectional view of the actuator provided in an embodiment of this disclosure; Figure 5A schematic diagram showing the connection between the middleware and the pen refill holder provided in an embodiment of this disclosure; Figure 6 This is a schematic diagram of the push rod provided in an embodiment of the present disclosure; Figure 7 A perspective sectional view of the pen body provided in an embodiment of this disclosure; Figure 8 A perspective sectional view of the needle cap provided in an embodiment of this disclosure; Figure 9 This is a cross-sectional view of the actuator provided in an embodiment of the present disclosure within the actuation sleeve; Figure 10 This is a cross-sectional view of the actuator disengaging from the excitation sleeve according to an embodiment of this disclosure.
[0023] In the picture: 1. Button; 2. Actuator; 21. Elastic tongue; 22. Protrusion; 23. Stop; 24. Groove; 3. Intermediate component; 31. Hook; 32. Boss; 4. Pen refill holder; 41. First limit switch; 5. Push rod; 51. Annular groove; 52. Annular boss; 6. Piston rod spring; 7. Excitation sleeve; 71. First step; 72. Outer wall protruding ring; 73. Second step; 8. Needle tip cover spring; 9. Medicine bottles; 10. Pen body sleeve; 101. Second limit; 102. Third limit; 103. External viewing window; 11. Needle cap; 111. Fourth limit switch; 112. Internal viewing window; 12. Rubber stopper; 13. Hook platform. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] In this document, when it is mentioned that a first component is located on a second component, this can mean that the first component can be directly formed on the second component, or that a third component can be inserted between the first and second components. Furthermore, in the accompanying drawings, the thickness of the components may be exaggerated or reduced for the purpose of effectively describing the technical content.
[0026] In this document, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. As used herein, expressions such as “at least one of…” modify the entire list of elements when following a list of elements, rather than individual elements in the list. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.
[0027] The terminology used herein is for the purpose of describing specific exemplary configurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may also be intended to include plural forms unless otherwise clearly stated herein. The terms “comprising,” “including,” and “having” are inclusive and thus specify the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein should not be construed as requiring them to be performed in the specific order discussed or shown, unless specifically identified as such. Additional or alternative steps may be employed.
[0028] As used herein, the phrases “in one embodiment,” “according to one embodiment,” “in some embodiments,” etc., generally refer to the fact that a particular feature, structure, or characteristic following the phrase can be included in at least one embodiment of this disclosure. Therefore, a particular feature, structure, or characteristic can be included in more than one embodiment of this disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, the terms “example,” “exemplary,” etc., are used to “serve as an example, instance, or illustration.” Any implementation, aspect, or design described herein as “example” or “exemplary” is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. Rather, the use of the terms “example,” “exemplary,” etc., is intended to present concepts in a specific manner.
[0029] Research has revealed shortcomings in existing technologies: the injection pen also faces significant challenges during transportation and storage; specifically, the pen can be activated without authorization; in particular, its activation mechanism, such as the needle cap, is easily triggered by accidental drops, squeezing, or improper operation, or by unintended users (such as children or unsuspecting others) accidentally activating the mechanism; this not only leads to waste of medication but may also result in needle prick injuries, affecting the overall safety of the injection pen.
[0030] Therefore, how to prevent the injection pen from being activated without authorization is a technical problem that urgently needs to be solved in this field.
[0031] The shortcomings of the above solutions are the result of the inventor's practical experience and careful research. Therefore, the discovery process of the above problems and the solutions proposed in this disclosure should be considered as the inventor's contribution to this disclosure.
[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0033] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0034] like Figure 1 As shown, some embodiments provide a safety-type automatic injection pen, which may include: a pen body sleeve 10, an actuator 2, an actuation sleeve 7, and a push rod 5.
[0035] Specifically, a button 1 is provided at the distal end of the pen sleeve 10, and a needle cover 11 is provided at the proximal end. An actuator 2 is axially movable within the pen sleeve 10, its distal end connected to the button 1, and its proximal end having a protrusion 22. An activation sleeve 7 is axially movable and fitted onto the outer wall of the actuator 2. When the injection pen is not activated, the protrusion 22 is radially limited within the activation sleeve 7. A push rod 5 is fitted inside the actuator 2, and its outer wall has an annular groove 51. A pre-compressed plunger spring 6 is housed inside the push rod 5, which abuts against the rubber stopper 12 to inject the medication. The protrusion 22 is engaged within the annular groove 51. Because the protrusion 22 is radially limited by the activation sleeve 7 and cannot open, the push rod 5 is locked, preventing it from being pushed out by the plunger spring 6. The proximal end is closer to the needle, and the distal end is further away from the needle.
[0036] like Figure 2 As shown, the distance between the protrusion 22 and the proximal end of the excitation sleeve 7 is H1+H2. When the needle cover 11 presses against the injection site, the needle cover 11 drives the excitation sleeve 7 to move a first displacement H1 relative to the actuator 2 in the direction away from the needle, that is, the distal end of the injection pen. When the button 1 is pressed, the actuator 2 moves a second displacement H2 relative to the excitation sleeve 7 in the direction of the needle, that is, in the direction of the proximal end of the injection pen. When both the first displacement H1 and the second displacement H2 occur, the protrusion 22 disengages from the circumferential limit of the excitation sleeve 7 and separates from the annular groove 51 to release the plunger rod spring 6, allowing the push rod 5 to drive the rubber stopper 12 to move towards the needle to complete the injection.
[0037] The safety-type automatic injection pen provided by this invention ensures that the injection process requires two independent confirmation actions—a first displacement H1 and a second displacement H2—through the coordinated action of components such as the button 1, actuator 2, activation sleeve 7, push rod 5, and needle cover 11 on the pen body sleeve 10, before it can be triggered. The conditions for achieving H1 and H2 are not sequential. Furthermore, when the needle cover 11 presses against the injection site and H1 occurs, if the user wants to cancel the injection, they simply move the injection pen away from the injection site, and the needle cover 11 returns to its initial position. Similarly, when the button 1 is pressed and H2 occurs, if the user wants to cancel the injection, releasing the button 1 will also return it to its initial position. When not activated, the protrusion 22 of the actuator 2 is engaged within the annular groove 51 of the push rod 5, and the actuator 2 is radially limited by the activation sleeve 7, thereby constraining the plunger spring 6 and preventing it from being activated.
[0038] See Figures 1 to 2 When activated, the pen cap is removed, the needle sleeve 11 presses against the injection site, and the activation sleeve 7 moves a first displacement H1 relative to the actuator 2 away from the needle. Then, the button 1 is pressed, which drives the actuator 2 to move a second displacement H2 relative to the activation sleeve 7 towards the needle. Only when both displacements H1 and H2 are successfully completed will the activation sleeve 7 release the radial constraint on the actuator 2, thereby causing the protrusion 22 to disengage from the annular groove 51. The push rod 5 is driven by the plunger rod spring 6 to complete the injection.
[0039] Alternatively, after removing the pen cap, press button 1 first, and then press the needle cover 11 against the injection site. This application does not limit the activation sequence; as long as the displacement of H1 and H2 is achieved, the injection pen can be activated.
[0040] Therefore, the technical solution of this application, through a dual confirmation mechanism, improves the safety of the injection pen on the one hand, effectively preventing accidental activation due to a single accidental action such as accidental touch of button 1 or accidental pressure, thus greatly enhancing the safety of the injection pen. On the other hand, it also gives users the opportunity to temporarily cancel the injection, increasing flexibility and improving the user experience.
[0041] See Figure 2 and Figure 5 The injection pen may also include an intermediate component 3 and a refill holder 4, with the intermediate component 3 located axially between the actuator 2 and the refill holder 4, such as... Figure 2 As shown, combined with Figure 6 The intermediate component 3 has a hook 31 at its distal end, which engages with the annular groove 51 and is axially adjacent to the actuator 2. The intermediate component 3 has a boss 32 at its proximal end, and the pen refill holder 4 has a first limit 41 at its end adjacent to the intermediate component 3, with the boss 32 and the first limit 41 acting as a stop. (See also...) Figure 1 and Figure 2When button 1 is pressed, actuator 2 moves a second displacement H2 relative to the trigger sleeve 7 along the proximal direction of the injection pen. Simultaneously, it moves intermediate component 3 and pen cartridge holder 4 together along the proximal end by H2. The movement of pen cartridge holder 4 causes the proximal end of the vial 9 to move, thus the needle also moves closer to the proximal end. However, the needle has not yet protruded from the needle sleeve 11, so injection cannot be performed yet. If the needle sleeve 11 continues to press against the skin, after the needle sleeve 11 moves H1 relative to the trigger sleeve 7, the needle protrudes and can be inserted into the skin for injection.
[0042] Similarly, see Figure 1 and Figure 2 If the needle cap 11 is pressed against the skin first, and the needle cap 11 moves H1 relative to the excitation sleeve 7, the needle cannot be exposed for injection. It is necessary to continue pressing the button 1 to move the actuator 2 along the proximal end of the injection pen relative to the excitation sleeve 7 by a second displacement H2, thereby pushing the pen cartridge holder 4 to move H2 along the needle direction, so that the needle can be exposed for injection.
[0043] refer to Figure 2 and Figure 7 To ensure that the displacement of the actuator 2 is H2 when the button 1 is pressed, a second limit 101 is provided at the end of the pen sleeve 10 near the needle tip. The actuator 2 drives the intermediate part 3 and the pen tip support 4 to move together along the needle tip direction until the pen tip support 4 stops at the second limit 101, and H2 is achieved.
[0044] like Figure 4 The figure shown is an exploded view of the connection structure between actuator 2 and button 1. A groove 24 is provided at the distal end of actuator 2, and a hook 13 is provided at button 1. The hook 13 is hooked to the groove 24. When button 1 is pressed, button 1 can drive actuator 2 to move towards the proximal end of the injection pen. When button 1 is released, actuator 2 drives button 1 to return to the distal end.
[0045] See Figure 1 The injection pen also includes: a needle cover spring 8, which is sleeved on the surface of the excitation sleeve 7. One end of the needle cover spring 8 abuts against the outer wall protrusion ring 72 of the excitation sleeve 7, and the other end is adapted to abut against the stop portion 23 (marked on...). Figure 4 When the first displacement H1 or the second displacement H2 occurs, the needle cover spring 8 is compressed. After the injection is completed, the needle cover cylinder 11 is displaced from the injection part, and the needle cover spring 8 drives the excitation sleeve 7 to move the needle cover cylinder 11 towards the needle to cover the needle. At the same time, the needle cover spring 8 drives the actuator 2 to move towards the distal end of the injection pen, thereby resetting the button 1.
[0046] Specifically, see Figure 1 and Figure 2When the needle cap 11 presses against the injection site, the outer wall protrusion 72 of the actuation sleeve 7 applies an axial force to the needle cap spring 8 in the direction away from the needle. When button 1 is pressed, the stop part 23 applies an axial force to the needle cap spring 8 in the direction of the needle. That is, when the user actuates and uses the device, i.e., completes the H1 or H2 displacement, the needle cap spring 8 is compressed, thereby storing elastic potential energy for the needle cap spring 8. When the injection is completed and the external pressure disappears, such as when the finger leaves button 1, the needle cap 11 leaves the skin, the needle cap spring 8 is released, and the actuation sleeve 7 drives the needle cap 11 to move towards the needle, covering the needle. At the same time, the actuator 2 is driven to move towards the distal end of the injection pen, causing button 1 to reset.
[0047] like Figure 2 and Figure 9 As shown, the inner wall of the excitation sleeve 7 is provided with a first step 71; wherein, in the unexcited state, the elastic tongue 21 of the injection pen is locked within the first step 71. That is to say, in the unexcited state, the elastic tongue 21 at the proximal end of the actuator 2 is radially constrained by the first step 71 and cannot open outward. Furthermore, the protrusion 22 of the actuator 2 is locked within the annular groove 51 of the push rod 5, thereby firmly locking the actuator 2 and the push rod 5 radially within the excitation sleeve 7, thus ensuring the safe locking of the injection pen in the storage and carrying state and preventing accidental excitation.
[0048] See Figure 9 and Figure 10 The inner wall of the excitation sleeve 7 is provided with a second step 73. After injection, the needle cover 11 is displaced from the injection site, and the needle cover spring 8 drives the excitation sleeve 7 to move towards the needle. The elastic tongue 21 abuts against the second step 73. Thus, the elastic tongue 21 is abutted against by the second step 73 in the axial direction, and the needle cover 11 cannot be pushed to move towards the needle, effectively preventing the needle from being exposed again after injection.
[0049] like Figures 7 to 8 As shown, a third limit 102 is provided on the pen body sleeve 10. The third limit 102 is located on the side away from the needle tip of the second limit 101. The needle cover 11 is provided with a fourth limit 111. After the injection is completed, the needle cover 11 is displaced from the injection part. The needle cover spring 8 drives the needle cover 11 to move towards the needle tip until the third limit 102 and the fourth limit 111 stop.
[0050] like Figures 7 to 8As shown, the pen sleeve 10 has an external viewing window 103, and the third limiter 102 is a protrusion arranged around the distal end of the external viewing window 103; the needle cover 11 has an internal viewing window 112 corresponding to the external viewing window 103, and the fourth limiter 111 is the distal sidewall of the internal viewing window 112. The needle cover 11, as a whole, always slides against the inner wall of the pen sleeve 10. When the third limiter 102 collides with the fourth limiter 111, a rigid mechanical stop is formed, thereby limiting the final position of the needle cover 11 in the direction of the needle tip and completing the reset. This limiting mechanism relies entirely on the impact stop of the internal axial structure, rather than through the radial reduction of the needle cover 11 body or the snap-fit mechanism. The structure is simple, stable, reliable, and highly versatile, and can be adapted to needle covers with various inner diameters.
[0051] See Figures 5 to 6 The distal end of the plunger 5 is provided with an annular protrusion 52. After the injection pen is activated, the plunger 5 drives the rubber stopper 12 to move towards the needle. When the annular protrusion 52 slides past the latch 31, it emits an injection completion prompt sound. The annular protrusion 52 can also be located at the proximal end of the plunger 5, and when it slides past the latch 31, it emits an injection start prompt sound. Alternatively, the plunger 5 can have an annular protrusion 52 from both the proximal and distal ends, meaning that a prompt sound will be emitted throughout the entire injection process, and the silence of the prompt sound indicates that the injection is complete. This provides the user with clear auditory feedback, allowing them to safely remove the injection pen without visual confirmation, greatly enhancing the reliability and safety of the operation.
[0052] See Figure 1 and Figure 5 The boss 32 of the intermediate part 3 abuts against the end face of the medicine bottle 9, thus limiting the axial movement of the medicine bottle 9.
[0053] Specifically, see Figure 5 The boss 32 on the intermediate component 3 serves as the axial positioning surface for the vial 9. The direct contact between the boss 32 and the end face of the vial 9 restricts the free movement of the vial 9 within the pen refill holder 4 away from the needle. This achieves stable and reliable axial fixation of the vial 9, effectively preventing movement during transportation or operation and ensuring the precise and stable position of the vial 9 before injection.
[0054] In summary, combined with the appendix Figures 1 to 9 Describe the overall workflow: (a) When not stimulated In the non-use state, all components are in a stable locked position. The elastic tongue 21 at the proximal end of the actuator 2 is engaged in the first step 71 on the inner wall of the actuation sleeve 7, restricting its radial movement and preventing it from opening. At the same time, the protrusion 22 of the actuator 2 is engaged in the annular groove 51 of the push rod 5, preventing the pre-compressed plunger rod spring 6 inside from releasing. The hook 31 of the intermediate component 3 is also engaged in the annular groove 51 of the push rod 5, and the boss 32 at its other end stops with the first limit 41 of the pen refill holder 4, axially limiting the medicine bottle 9 inside the pen refill holder 4. The needle cover spring 8 is in a natural or slightly compressed state.
[0055] (II) Stimulation and Injection In use, first remove the pen cap and press the needle sleeve 11 against the injection site. The actuation sleeve 7 moves a first displacement H1 away from the needle relative to the actuator 2. Then press button 1, and the actuator 2 moves a second displacement H2 relative to the actuation sleeve 7 towards the needle, pushing the intermediate part 3 and the pen refill holder 4 forward along with the medicine bottle 9 and the needle until the pen refill holder 4 stops at the second limit 101 on the pen sleeve 10. When both displacements H1 and H2 are completed, the radial constraint of the first step 71 on the elastic tongue 21 is released, and the protrusion 22 of the actuator 2 disengages from the annular groove 51 of the push rod 5. The plunger rod spring 6 drives the push rod 5 and the rubber stopper 12 forward at high speed to complete the injection. When the annular boss 52 on the push rod 5 slides past the hook 31 of the intermediate part 3, a prompt sound is emitted, indicating that the injection is complete. During this process, the needle sleeve spring 8 is further compressed and stores energy due to the actuation action.
[0056] Alternatively, after removing the pen cap, press button 1 first. The actuator 2 moves a second displacement H2 relative to the excitation sleeve 7 towards the needle. Then, press the needle cover 11 against the injection site. The excitation sleeve 7 moves a first displacement H1 relative to the actuator 2 away from the needle. At this time, the push rod 5 is released, and the needle is exposed and inserted into the skin, starting the injection.
[0057] (III) Reset the needle cap 11 After injection, the user removes their thumb and withdraws the pen from the skin. Once the external pressure disappears, the compressed needle cover spring 8 releases, driving the actuation sleeve 7 to move the needle cover 11 towards the needle, thus covering it. When the needle cover 11 reaches its endpoint, its internal fourth limit 111 impacts the third limit 102 on the inner wall of the pen sleeve 10, forming a hard stop and completing the reset. Simultaneously, the actuator 2, pushed distally by the needle cover spring 8 due to the release of button 1, has its elastic tongue 21 engaged within the second step 73 on the inner wall of the actuation sleeve 7, effectively preventing the needle from being exposed again after the needle cover 11 is pressed.
[0058] In the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.
[0059] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention 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, and therefore should not be construed as a limitation of the invention. Furthermore, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence unless expressly indicated herein. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed above may be referred to as a second element, component, region, layer, or segment.
[0060] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. A safety-type automatic injection pen, characterized in that, include: The pen body sleeve (10) has a button (1) at its far end and a needle cover (11) at its near end. The actuator (2) is axially movable inside the pen body sleeve (10), its distal end is connected to the button (1), and its proximal end is provided with a protrusion (22). The excitation sleeve (7) is axially movable and sleeved on the outer wall of the actuator (2). When the injection pen is not excited, the actuator (2) is radially limited inside the excitation sleeve (7). Push rod (5), which is sleeved inside the actuator (2); The outer wall of the push rod (5) is provided with an annular groove (51), and the protrusion (22) is stuck in the annular groove (51); The push rod (5) contains a plunger rod spring (6). When the needle cap (11) presses against the injection site, the excitation sleeve (7) moves a first displacement H1 relative to the actuator (2) in the direction away from the needle. When the button (1) is pressed, the actuator (2) moves a second displacement H2 relative to the excitation sleeve (7) in the direction of the needle. When both the first displacement H1 and the second displacement H2 occur, the protrusion (22) separates from the annular groove (51) to release the plunger rod spring (6), allowing the push rod (5) to drive the rubber stopper (12) to move towards the needle to complete the injection. The injection pen also includes: A needle cover spring (8) is sleeved on the surface of the excitation sleeve (7). One end of the needle cover spring (8) abuts against the outer wall protrusion ring (72) of the excitation sleeve (7), and the other end is adapted to abut against the stop part (23) of the actuator (2). When the first displacement H1 or the second displacement H2 occurs, the needle cover spring (8) is compressed. After the injection is completed, the needle cover (11) is displaced from the injection site, and the needle cover spring (8) drives the excitation sleeve (7) to move the needle cover (11) toward the needle to cover the needle.
2. The injection pen as described in claim 1, characterized in that, It also includes an intermediate component (3) and a pen tip holder (4). In the axial direction, the intermediate component (3) is located between the actuator (2) and the pen tip holder (4). When the button (1) is pressed, the actuator (2) drives the intermediate component (3) and the pen tip holder (4) to move together along the needle direction.
3. The injection pen as described in claim 2, characterized in that, One end of the intermediate component (3) is provided with a hook (31) and the other end is provided with a boss (32). The pen refill bracket (4) is provided with a first limit (41) at the end adjacent to the intermediate component (3). The hook (31) is engaged in the annular groove (51), and the boss (32) stops the first limit (41).
4. The injection pen as described in claim 2, characterized in that, The pen sleeve (10) is provided with a second limit (101) at the end near the needle tip. The actuator (2) drives the intermediate part (3) and the pen tip support (4) to move together along the needle tip direction until the pen tip support (4) stops at the second limit (101).
5. The injection pen as described in claim 4, characterized in that, The actuator (2) has an elastic tongue (21) at the other end away from the protrusion (22). The inner wall of the excitation sleeve (7) is provided with a first step (71); In the unactivated state, the elastic tongue (21) of the injection pen is stuck in the first step (71).
6. The injection pen as described in claim 5, characterized in that, The inner wall of the excitation sleeve (7) is provided with a second step (73). After the injection is completed, the needle cover (11) is displaced from the injection part, and the needle cover spring (8) drives the excitation sleeve (7) to move towards the needle. The elastic tongue (21) abuts against the second step (73).
7. The injection pen as described in claim 5, characterized in that, The pen body sleeve (10) is provided with a third limit (102), which is located on the side away from the needle tip from the second limit (101). The needle cover sleeve (11) is provided with a fourth limit (111). After the injection is completed, the needle cover sleeve (11) is displaced from the injection part, and the needle cover spring (8) drives the needle cover sleeve (11) to move towards the needle tip until the third limit (102) and the fourth limit (111) stop.
8. The injection pen as described in claim 3, wherein the push rod (5) is provided with an annular boss (52), the push rod (5) drives the rubber stopper (12) to move toward the needle, and the annular boss (52) provided on the push rod (5) slides past the hook (31) and emits an injection completion prompt sound.
9. The injection pen as described in claim 3, wherein the boss (32) of the intermediate part (3) abuts against the end face of the vial (9) to axially limit the vial (9).