A disposable injection pen

Abstract

The utility model relates to a kind of disposable injection pen, at least including needle holder, pen barrel and the anti-disassembly connecting structure for connecting needle holder and pen barrel, the distal end of needle holder is provided with needle head fixed part for fixing needle head, the proximal end of needle holder is provided with opening, anti-disassembly connecting structure includes clamping groove and connecting column, clamping groove is set to the proximal end side of needle holder and penetrates the cavity wall of needle holder, connecting column is set to the distal end of pen barrel, the outside wall of connecting column is provided with gap, gap is provided with elastic cantilever, the free end of elastic cantilever is provided with the outwardly protruding boss of radial;When needle holder and pen barrel are assembled, boss passes through the clamping groove from the side of inner cavity.Compared with prior art, the utility model has the advantages that: the connecting structure of the clamping groove of needle holder and the boss of the elastic cantilever on connecting column is used, needle holder can be quickly assembled to pen barrel and is not easy to disassemble, avoid the problem of drug misuse and needle infection caused by needle head being reused.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, specifically to a disposable injection pen. Background Technology

[0002] In clinical practice, syringes are among the most commonly used medical devices, primarily used for the aspiration, delivery, or injection of medications. Specialized syringes, such as interferon or hormone injection pens, resemble pens in shape; therefore, the syringe barrel is sometimes referred to as the pen barrel. The medication is often pre-stored in the cartridge of the pen barrel at the factory. Before use, the needle hub and pen barrel are usually separate; during use, they are typically connected via a Luer connector on the needle hub and pen barrel. Luer connectors come in two types: sliding and fixed. The threaded fixed type offers better connection strength than the friction-based sliding type, effectively preventing accidental detachment of the needle hub and pen barrel. However, the threaded structure is also easily disassembled in the reverse direction. To avoid misuse of specialized medications, needle contamination, and other improper use, these specialized syringes are usually for single use. However, the easily detachable connection structure allows for improper reuse.

[0003] In existing technologies, the connection structure between the needle hub and the pen barrel in disposable injection pens has been optimized. For example, Chinese patent document CN221332250U discloses an insulin injection pen needle mounting structure. The output end of the syringe is connected to a connecting tube, and the outer wall of the connecting tube is connected to an elastic snap-fit ​​structure. The outer ring of the needle tip is connected to a protruding ring that engages with the elastic snap-fit ​​structure. By pressing the elastic snap-fit ​​structure, the needle can be released, separating it from the connecting tube and quickly removing it. Conversely, the needle can be placed back into the connecting tube, where the elastic snap-fit ​​structure engages with the protruding ring. Compared to the threaded structure in a fixed Luer connector, the snap-fit ​​structure aims to achieve rapid needle installation and removal, significantly reducing assembly and disassembly time.

[0004] Chinese patent document CN213312523U discloses an improved snap-fit ​​syringe. Two sets of locking blocks are symmetrically installed on the outer side of the syringe barrel near the nozzle. A latex head is snapped into the nozzle, and a needle is fixedly connected to the other end of the latex head. Two sets of symmetrical L-shaped slots are formed on the inner wall of the latex head, and the slot positions correspond to the positions of the locking blocks on the outer side of the nozzle. The snap-fit ​​rotational connection is added to the existing frictional connection between the syringe barrel and the latex head to increase the connection's strength. This rotational snap-fit ​​connection can also be quickly disassembled by rotating in the opposite direction.

[0005] In summary, existing technical solutions have improved the connection structure between the needle hub and the pen holder in terms of quick assembly and disassembly of the syringe or the stability of the connection. However, problems such as easy disassembly of the needle hub and the possibility of improper reuse still exist, leading to drug misuse and needle infection. Summary of the Invention

[0006] The technical problem to be solved by this utility model is to provide a disposable injection pen that allows the needle hub to be quickly assembled onto the pen holder. The assembly is convenient and not easy to disassemble, thus avoiding the problems of drug misuse and needle infection caused by the reuse of needles.

[0007] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows: A disposable injection pen, comprising at least: The needle hub has a hollow internal design and an inner cavity. The distal end of the needle hub is provided with a needle fixing part for fixing the needle tip, and the proximal end of the needle hub is provided with an opening. A pen holder, wherein the pen holder has a hollow interior and is provided with a medicine cavity; It also includes a detachable connection structure for connecting the needle holder and the pen holder, the detachable connection structure comprising: A slot is provided on one side of the proximal end of the needle hub and penetrates the cavity wall of the needle hub; A connecting post is provided at the far end of the pen holder. A notch is provided on the outer side wall of the connecting post. An elastic cantilever is provided at the notch of the connecting post. A radially outward protrusion is provided at the free end of the elastic cantilever. When the needle seat and the pen holder are assembled, the protrusion passes through the slot from one side of the inner cavity.

[0008] The beneficial effects of this plan are:

[0009] (1) When assembling the needle holder and the pen holder, as the connecting post of the pen holder enters the inner cavity of the needle holder through the opening of the needle holder, the protrusion of the elastic cantilever is pressed against the inner wall of the needle holder, causing the elastic cantilever to bend inward at the notch. When the protrusion reaches the slot position, the elastic cantilever loses pressure and the protrusion passes through the slot from one side of the inner cavity. Compared with the threaded structure in the prior art, the present invention adopts a connection structure composed of the slot on the needle holder and the protrusion of the elastic cantilever on the connecting post, which enables the needle holder to be quickly assembled onto the pen holder, making the assembly more convenient.

[0010] (2) When the needle holder and pen holder are assembled, the elastic cantilever is located in the inner cavity of the needle holder. The protrusion passes through the slot from the inner cavity and supports the protrusion through the proximal end face of the slot, thus preventing the pen holder from being removed from the needle holder. Compared with the snap-fit ​​structure and rotary snap-fit ​​structure in the prior art, the anti-disassembly connection structure of this utility model has the function of preventing the needle holder from being disassembled. The operator cannot directly disconnect the connection through the elastic cantilever. In addition, in order to support the protrusion, the cavity wall at the slot of the needle holder itself has a certain thickness. It is difficult for the operator to directly press the protrusion by hand to make the outer edge of the protrusion disengage from the slot and remove the needle holder from the pen holder, thereby avoiding the problems of drug misuse and needle infection caused by the reuse of the needle.

[0011] Furthermore, a first guide surface is provided on the inner wall of the opening of the needle holder.

[0012] The beneficial effects of this solution are as follows: by setting the first guide surface, on the one hand, it allows the connecting post to be better inserted into the inner cavity of the needle seat; on the other hand, it allows the protrusion on the elastic cantilever to gradually bend towards the inside of the notch by contacting the first guide surface, making assembly more convenient.

[0013] Furthermore, the first guide surface is an arc surface or an inclined surface.

[0014] Furthermore, the elastic cantilever is provided with a second guide surface at the distal end of the protrusion.

[0015] Furthermore, the slot is a square hole or a semi-circular hole.

[0016] Furthermore, a flange is provided on the outer side wall of the proximal end of the needle seat, and the distal end of the flange is connected to the slot.

[0017] Furthermore, the distal end of the flange is provided with a groove communicating with the slot in the radial direction, and the protrusion passes through the slot and is placed into the groove.

[0018] The beneficial effects of this solution are as follows: the needle holder, combined with the flange on the slot, supports the protrusion on the elastic cantilever, which can improve the reliability of the connection; in addition, by placing the part of the protrusion protruding from the slot into the groove of the flange, the protrusion on the elastic cantilever can be protected, further preventing the operator from disassembling or accidentally disassembling the needle holder through the protrusion, thus improving the safety of the connection between the needle holder and the pen holder.

[0019] Furthermore, it also includes a needle holder housing, which is sleeved on the outside of the needle holder and fixedly connected to the needle holder.

[0020] Furthermore, a window is provided on the outer wall of the needle holder housing corresponding to the slot.

[0021] The beneficial effect of this solution is that when the operator installs the needle holder onto the pen holder through the needle holder housing, the window set on the needle holder housing allows the operator to clearly see the position of the slot and clearly observe whether the protrusion has passed through the slot, thus improving the accuracy of assembly.

[0022] Furthermore, the protrusion does not extend beyond the window of the pin housing after passing through the slot.

[0023] The beneficial effect of this solution is that the part of the protrusion exposed in the slot does not extend out of the window, which can further prevent the operator from contacting the protrusion, thereby avoiding the operator from disassembling or accidentally disassembling the pin seat through the protrusion, and improving the safety of the connection. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a disposable injection pen according to this embodiment.

[0025] Figure 2 This is a structural schematic diagram of the disposable injection pen from another perspective in this embodiment.

[0026] Figure 3 This is a schematic diagram of the needle holder structure in this embodiment.

[0027] Figure 4 This is a schematic diagram of the needle holder from another perspective in this embodiment.

[0028] Figure 5 This is a schematic diagram of the pen holder in this embodiment.

[0029] Figure 6 This is a schematic diagram of the needle holder housing in this embodiment.

[0030] Figure 7 This is a schematic diagram of the syringe structure after the needle hub housing is installed in this embodiment.

[0031] Figure 8 This is a schematic diagram of the syringe after the needle hub housing is installed, from another perspective.

[0032] Figure 9 This is a schematic diagram of the anti-disassembly connection structure of the disposable injection pen in this embodiment.

[0033] Figures 1-9 middle: 1. Needle hub; 10. Inner cavity; 11. Needle fixing part; 12. Opening; 121. First guide surface; 13. Slot; 14. Flange; 141. Groove; 2. Pen holder; 20. Medicine cavity; 21. Connecting post; 211. Notch; 212. Elastic cantilever; 2121. Protrusion; 2122. Second guide surface; 3. Needle; 4. Needle base housing; 41. Striped texture; 42. Window. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0035] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0036] In the description of this utility model, it should be noted that, 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, an integral connection, or a detachable connection; they can refer to the internal connection of two components; they can refer to a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0037] In the description of this utility model, "proximal end" refers to the end closer to the operator, and "distal end" refers to the end further away from the operator, that is, closer to the patient.

[0038] like Figure 1-2 As shown, a disposable injection pen according to this embodiment includes a needle holder 1, a pen barrel 2, and a needle 3. In this embodiment, the structure of the needle holder 1 is as follows: Figure 3-4 As shown, the needle holder 1 has a hollow interior with an inner cavity 10. The distal end of the needle holder 1 has a needle fixing part 11 for fixing the needle tip 3, and the proximal end of the needle holder 1 has an opening 12. In this embodiment, the structure of the pen holder 2 is as follows... Figure 5 As shown, the pen holder 2 has a hollow interior and a medicine cavity 20, and a connecting post 21 is provided at the distal end of the pen holder 2. The connecting post 21 of the pen holder 2 is inserted into the inner cavity 10 of the needle holder 1 through the opening 12 of the needle holder 1.

[0039] As a special feature of this embodiment, it also includes an anti-disassembly connection structure for connecting the needle holder 1 and the pen holder 2, the anti-disassembly connection structure as follows: Figure 1 , Figure 2 , Figure 7 , Figure 8 and Figure 9 As shown. The anti-disassembly connection structure includes a slot 13 and a connecting post 21. In this embodiment, the structure of the pin holder 1 is as follows. Figure 3-4 As shown, the slot 13 is located on the proximal side of the needle holder 1 and penetrates the cavity wall of the needle holder 1. In this embodiment, the structure of the pen holder 2 is as follows: Figure 5As shown, a notch 211 is provided on the outer wall of the connecting post 21, and an elastic cantilever 212 is provided at the notch 211 of the connecting post 21. The free end of the elastic cantilever 212 is provided with a radially outward protrusion 2121. When the needle holder 1 and the pen holder 2 are assembled, the protrusion 2121 passes through the slot 13 from one side of the inner cavity 10.

[0040] The advantage of this design is that, during the assembly of the needle holder 1 and the pen holder 2, as the connecting post 21 of the pen holder 2 enters the inner cavity 10 of the needle holder 1 through the opening 12, the protrusion 2121 of the elastic cantilever 212 presses against the inner wall of the needle holder 1, causing the elastic cantilever 212 to be compressed and bend inward at the notch 211. When the protrusion 2121 reaches the slot 13, the elastic cantilever 212 loses pressure, allowing the protrusion 2121 to pass through the slot 13 from one side of the inner cavity 10. This allows the needle holder 1 to be quickly assembled onto the pen holder 2, making assembly more convenient.

[0041] Another advantage of this design is that when the needle holder 1 and the pen holder 2 are assembled, the elastic cantilever 212 is located in the inner cavity 10 of the needle holder 1. The protrusion 2121 passes through the slot 13 from the inner cavity 10, and supports the protrusion 2121 through the proximal end face of the slot 13, thus preventing the pen holder 2 from being dislodged from the needle holder 1. This prevents the needle holder 1 from being disassembled, and the operator cannot directly disconnect it through the elastic cantilever 212. In addition, in order to support the protrusion 2121, the cavity wall of the slot 13 of the needle holder 1 itself has a certain thickness, making it difficult for the operator to directly press the protrusion 2121 by hand to disengage the outer edge of the protrusion 2121 from the slot 13 and remove the needle holder 1 from the pen holder 2. This avoids problems such as drug misuse and needle infection caused by the reuse of the needle 3.

[0042] Preferably, in this embodiment, the structure of the needle holder 1 is as follows: Figure 3-4 As shown. The card slot 13 is a square hole. It should be noted that in this embodiment, the card slot 13 being set as a square hole is only a preferred embodiment. Those skilled in the art should understand that the card slot 13 can also be set as a semi-circular hole, etc.

[0043] Preferably, in this embodiment, a first guide surface 121 is provided on the inner wall of the opening 12 of the needle holder 1. Further, in this embodiment, the first guide surface 121 is an arc surface. It should be noted that in this embodiment, the first guide surface 121 being an arc surface is merely a preferred implementation; those skilled in the art should understand that the first guide surface 121 can also be an inclined surface, etc. Further, in this embodiment, the structure of the pen holder 2 is as follows... Figure 5 As shown. The elastic cantilever 212 is further provided with a second guide surface 2122 at the distal end of the protrusion 2121.

[0044] The advantage of this design is that the connecting post 21 can be quickly inserted into the inner cavity 10 of the needle holder 1 through the first guide surface 121 at the opening 12. In addition, the protrusion 2121 on the elastic cantilever 212 contacts the first guide surface 121 through the second guide surface 2122, guiding the elastic cantilever 212 to gradually bend towards the inside of the notch 211, making assembly more convenient.

[0045] Preferably, in this embodiment, a flange 14 is provided on the outer side wall of the proximal end of the needle seat 1, and the distal end of the flange 14 is connected to the slot 13. Further, in this embodiment, a groove 141 communicating with the slot 13 is provided on the distal end of the flange 14 in the radial direction, and the protrusion 2121 passes through the slot 13 and is placed in the groove 141.

[0046] The advantage of this setup is that, based on the support of the proximal end face of the slot 13, the pin seat 1, combined with the flange 14, supports the protrusion 2121 on the elastic cantilever 212, which can improve the reliability of the connection.

[0047] Another advantage of this arrangement is that by inserting the part of the protrusion 2121 exposed in the slot 13 into the groove 141 of the flange 14, the protrusion 2121 can be protected, further preventing the operator from disassembling or accidentally disassembling the needle holder 1 through the protrusion 2121, thereby improving the safety of the connection between the needle holder 1 and the pen holder 2.

[0048] Preferably, this embodiment also includes a needle holder housing 4, the structure of which is as follows: Figure 6-8 As shown, the outer wall of the needle holder housing 4 is provided with a striped texture 41. The striped texture 41 is used to assist the operator in rotating the needle holder housing 4. Further, in this embodiment, a window 42 is provided on the outer wall of the needle holder housing 4 corresponding to the slot 13.

[0049] The advantage of this design is that when the operator installs the needle holder 1 onto the pen holder 2 through the needle holder housing 4, the window 42 provided on the needle holder housing 4 allows the operator to clearly see the position of the slot 13 and clearly observe whether the protrusion 2121 passes through the slot 13, thus improving the accuracy of assembly.

[0050] Preferably, in this embodiment, the syringe structure after the needle hub housing 4 is installed is as follows: Figure 7-9 As shown. The needle holder housing 4 is sleeved on the outside of the needle holder 1 and fixedly connected to the needle holder 1. Further, in this embodiment, the protrusion 2121 does not protrude from the window 42 of the needle holder housing 4 after passing through the slot 13.

[0051] The advantage of this design is that the part of the protrusion 2121 that protrudes from the slot 13 does not extend out of the window 42, which can further prevent the operator from contacting the protrusion 2121, thereby preventing the operator from disassembling or accidentally disassembling the needle holder 1 through the protrusion 2121, and improving the safety of the connection between the needle holder 1 and the pen holder 2.

[0052] In summary, the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A disposable injection pen, comprising at least: The needle seat (1) has a hollow interior and an inner cavity (10). The distal end of the needle seat (1) is provided with a needle fixing part (11) for fixing the needle (3). The proximal end of the needle seat (1) is provided with an opening (12). Pen holder (2), the pen holder (2) has a hollow interior and is provided with a medicine cavity (20); The feature is that it further includes an anti-disassembly connection structure for connecting the needle holder (1) and the pen holder (2), the anti-disassembly connection structure comprising: The slot (13) is located on the proximal side of the needle seat (1) and penetrates the cavity wall of the needle seat (1); A connecting post (21) is provided at the far end of the pen holder (2). A notch (211) is provided on the outer side wall of the connecting post (21). An elastic cantilever (212) is provided at the notch (211) of the connecting post (21). A radially outward protrusion (2121) is provided at the free end of the elastic cantilever (212). When the needle seat (1) and the pen holder (2) are assembled, the protrusion (2121) passes through the slot (13) from the inner cavity (10) side.

2. The single-use injection pen of claim 1, wherein, A first guide surface (121) is provided on the inner wall of the opening (12) of the needle seat (1).

3. The single-use injection pen of claim 2, wherein, The first guide surface (121) is an arc surface or an inclined surface.

4. The single-use injection pen of claim 1, wherein, The elastic cantilever (212) has a second guide surface (2122) at the far end of the protrusion (2121).

5. The single-use injection pen of claim 1, wherein, The slot (13) is a square hole or a semi-circular hole.

6. The disposable injection pen according to claim 1, characterized in that, A flange (14) is provided on the outer side wall of the proximal end of the needle seat (1), and the distal end of the flange (14) is connected to the slot (13).

7. The disposable injection pen according to claim 6, characterized in that, The distal end of the flange (14) is provided with a groove (141) communicating with the slot (13) in the radial direction, and the protrusion (2121) passes through the slot (13) and is placed in the groove (141).

8. The disposable injection pen according to claim 1, characterized in that, It also includes a needle holder housing (4), which is sleeved on the outside of the needle holder (1) and fixedly connected to the needle holder (1).

9. The disposable injection pen according to claim 8, characterized in that, A window (42) is provided on the outer wall of the needle holder housing (4) corresponding to the slot (13).

10. The disposable injection pen according to claim 9, characterized in that, The protrusion (2121) does not protrude from the window (42) of the pin housing (4) after passing through the slot (13).

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