Insulin injection pen

Abstract

The utility model discloses an insulin injection pen, and belongs to the technical field of medical instruments. Comprising a main body shell, a connecting sleeve and a medicine bin, and the main body shell is connected with the medicine bin through the connecting sleeve; the adjusting mechanism comprises a dosage rotating cylinder and a transmission pipe, the dosage rotating cylinder is arranged in the main body shell and is in threaded connection with the main body shell, and the transmission pipe is arranged in the dosage rotating cylinder and is in clutch connection with the dosage rotating cylinder; the driving mechanism is arranged in the transmission pipe, and the driving mechanism is matched with the connecting sleeve to form an injection sound production structure; the insulin injection pen is switched from a dose adjusting state to an injection state through up-down separation and reunion of the transmission tube, and injection administration is performed through the driving mechanism. The connecting sleeve is made of a plastic part with high hardness, even if the medicament bottle gives reactive force to the driving mechanism during injection, the matching precision between the driving mechanism and the connecting sleeve is not affected, the reliability of the injection sound production structure is improved, and the problem of deformation or failure possibly occurring after the reactive force during long-term injection administration is avoided.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of medical apparatus and instruments, and particularly relates to an insulin injection pen. BACKGROUND

[0002] In recent years, with the continuous rise of the incidence of diabetes, the demand for convenient, safe and efficient drug delivery devices has also increased. As an indispensable part of diabetes treatment, insulin injection pens have been widely used.

[0003] However, the existing insulin injection pen has the problems of inconvenient assembly, insufficient reliability of the overall structure after assembly, and low assembly precision of some parts due to unreasonable design, large number of required parts and complex structure. UTILITY MODEL CONTENTS

[0004] The utility model provides an insulin injection pen which is simple in structure, convenient to assemble and high in reliability after assembly.

[0005] The utility model can be implemented through the following technical solutions:

[0006] An insulin injection pen comprises:

[0007] A main body shell, a connecting sleeve and a cartridge, the main body shell and the cartridge are connected through the connecting sleeve, and the cartridge is used for installing a medicine bottle;

[0008] An adjusting mechanism, which comprises a dose drum and a transmission pipe, the dose drum is arranged in the main body shell and is threadedly connected with the main body shell, and the transmission pipe is arranged in the dose drum and is connected with the dose drum through clutching;

[0009] A driving mechanism, which is arranged in the transmission pipe, is used for pushing a plug in the medicine bottle to move forward and administer medicine, and the driving mechanism is matched with the connecting sleeve and forms an injection sound generating structure;

[0010] The insulin injection pen is switched from a dose adjusting state to an injection state through the up-down clutching of the transmission pipe, and the driving mechanism is used for injection and administration.

[0011] As a further improvement of the utility model, the transmission pipe has a clutching surface for clutching connection with the dose drum, the clutching surface has dose drum meshing teeth which protrude downward, and the dose drum has transmission pipe matching teeth which protrude upward, wherein,

[0012] During the dose adjusting process, the dose drum engaging teeth are separated from the transmission pipe mating teeth, at this time, the transmission pipe jumps up and down along with the rotation of the dose drum;

[0013] During the injection action, the transmission pipe is directly pressed down through the injection button and the dose drum engaging teeth are engaged with the transmission pipe mating teeth, at this time, the transmission pipe rotates synchronously with the dose drum.

[0014] As a further improvement of the utility model, the driving mechanism comprises a driving pipe, the driving pipe is arranged in the transmission pipe, the inner wall of the transmission pipe is provided with a guide rib along the axial direction, and the outer wall of the driving pipe is provided with a guide groove, and the guide rib is embedded in the guide groove.

[0015] As a further improvement of the utility model, the driving mechanism further comprises a screw rod, the screw rod is arranged in the driving pipe, and the cross section of the inner wall of the driving pipe and the cross section of the screw rod are both in a waist drum shape and are connected in cooperation.

[0016] As a further improvement of the utility model, the connecting sleeve is internally provided with a threaded seat connected integrally, the screw rod passes through the threaded seat and is threadedly connected therebetween, and the end of the screw rod close to the medicine bin passes through the threaded seat and is connected with a piston push piece.

[0017] As a further improvement of the utility model, the inner wall of the connecting sleeve is further provided with at least a pair of arc-shaped baffles, the arc-shaped baffles are spaced apart from the threaded seat and form a rotating space, the arc-shaped baffles are provided with limiting convex parts, the end part of the driving pipe is provided with a limiting baffle edge arranged in a ring shape, the limiting baffle edge is located in the rotating space between the arc-shaped baffles and the threaded seat, and the limiting convex parts are connected with the limiting baffle edge in an up-down manner.

[0018] As a further improvement of the utility model, an adjusting sound emitting ring is further arranged, which is located in the accommodating space between the top of the dose drum and the transmission pipe and is sleeved on the transmission pipe, the adjusting sound emitting ring and the dose drum are connected to form a forward adjusting sound emitting structure, and the adjusting sound emitting ring and the transmission pipe are connected to form a reverse adjusting sound emitting structure.

[0019] As a further improvement of the utility model, the inner wall of the dose drum is provided with a first thorn arranged in a one-way skewing manner, the outer wall of the adjusting sound emitting ring is provided with a first elastic tooth protruding outward, the first elastic tooth is connected with the first thorn in an up-down manner and forms the forward adjusting sound emitting structure.

[0020] As a further improvement of the utility model, the outer wall of the transmission pipe is provided with a second thorn, the second thorn and the first thorn are unidirectional deflection in opposite directions, the inner wall of the adjusting sound ring is provided with a second elastic tooth protruding inward, the second elastic tooth and the second thorn are buckled and form the reverse adjusting sound structure.

[0021] As a further improvement of the utility model, the inner wall of the connecting sleeve is provided with a third thorn, and the driving pipe is provided with a third elastic tooth protruding outward, the third thorn and the third elastic tooth cooperate to form the injection sound structure.

[0022] Compared with the prior art, the utility model has the beneficial effects that:

[0023] 1, the main body shell, the connecting sleeve, the medicine bin are respectively injection molded, it is convenient for production, and the connecting sleeve is connected with the main body shell and the medicine bin respectively by adopting the buckling mode, the stability and reliability of the overall structure are improved, and then the use precision of the product is ensured.

[0024] 2, the connecting sleeve is made of high-hardness plastic parts, even if the reaction force of the medicine bottle is given to the driving mechanism during injection, the cooperation precision between the driving mechanism and the connecting sleeve will not be affected, the reliability of the injection sound structure is improved, the deformation or failure problem that may occur after long-term injection is avoided, and the service life of the product is prolonged.

[0025] 3, the connecting sleeve is made of high-hardness plastic parts, the injection sound structure composed of the third thorn of the connecting sleeve and the third elastic tooth of the driving pipe can provide clearer and more explicit sound feedback, help the user to confirm the injection process, and also can reduce the risk of sound weakening caused by long-term use.

[0026] 4, the injection button directly contacts and presses the transmission pipe, no transition part is needed between the two, and the adjusting sound ring will not be deformed or have reduced cooperation precision due to the pressure generated when pressing the injection button, thereby ensuring that the adjusting sound ring will not accidentally come out during the up-and-down movement of the transmission pipe, and the reliability of the adjusting sound structure is enhanced.

[0027] 5, the threaded seat, the arc-shaped baffle and the limiting convex part cooperating with the driving pipe and the screw rod are integrally integrated on the connecting sleeve, without the need to add additional parts, further improving the convenience of product assembly and the reliability during use.

[0028] 6, only one part of the adjusting sound ring is needed to realize the sound generation when the dose drum rotates forward and reversely, the overall structure is optimized, the number of parts is simplified, and the overall structure is more reliable. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a sectional view of the insulin injection pen of the utility model;

[0030] Figure 2 is the utility model's Figure 1 the local enlarged view of A in the middle;

[0031] Figure 3 is the utility model's insulin injection pen distinguishes from Figure 1 the sectional view of the perspective angle;

[0032] Figure 4 is the utility model's Figure 3 the local enlarged view of B in the middle;

[0033] Figure 5 is the structure schematic diagram of the positive direction adjustment sound production structure of the utility model;

[0034] Figure 6 is the structure schematic diagram of the reverse direction adjustment sound production structure of the utility model;

[0035] Figure 7 is the structure schematic diagram of the injection sound production structure of the utility model;

[0036] Figure 8 is the structure schematic diagram of the dose rotating cylinder of the utility model;

[0037] Figure 9 is the structure schematic diagram of the transmission pipe of the utility model;

[0038] Figure 10 is the structure schematic diagram of the adjustment sound production ring of the utility model;

[0039] Figure 11 is the structure schematic diagram of the driving pipe of the utility model;

[0040] Figure 12 is the structure schematic diagram of the screw rod of the utility model;

[0041] Figure 13 is the structure schematic diagram of the connecting sleeve of the utility model;

[0042] Figure 14 is the structure schematic diagram of the medicine bin of the utility model;

[0043] Figure 15 is the structure schematic diagram of the insulin injection pen of the utility model.

[0044] In the drawing, 100, main body shell;

[0045] 200, connecting sleeve; 210, threaded seat; 220, arc baffle; 221, limiting convex part; 230, third thorn;

[0046] 300, cartridge; 310, cap;

[0047] 400, adjustment mechanism; 410, dose drum; 411, transmission tube mating tooth; 412, first thorn; 420, transmission tube; 421, dose drum engagement tooth; 422, second thorn; 423, guide rib; 430, adjustment sound ring; 431, first elastic tooth; 432, second elastic tooth;

[0048] 500, drive mechanism; 510, drive tube; 511, guide groove; 512, limiting stop; 513, third elastic tooth; 520, screw rod; 521, piston push piece; 530, memory ring;

[0049] 600, injection button. DETAILED DESCRIPTION

[0050] The following is a specific embodiment of the present application and further describes the technical method of the present application in combination with the drawings, but the present application is not limited to these embodiments.

[0051] As shown in the drawings, the present application provides an insulin injection pen, comprising: Figures 1-15

[0052] The main body shell 100, the connecting sleeve 200 and the cartridge 300 are connected through the connecting sleeve 200 between the main body shell 100 and the cartridge 300, and the cartridge 300 is used for installing a medicine bottle in it;

[0053] The adjustment mechanism 400 comprises a dose drum 410 and a transmission tube 420, the dose drum 410 is arranged in the main body shell 100 and is threadedly connected with the main body shell 100, and the transmission tube 420 is arranged in the dose drum 410 and is clutch-connected with the dose drum 410;

[0054] The drive mechanism 500 is arranged in the transmission tube 420 and cooperates with the connecting sleeve 200, the drive mechanism 500 is used for pushing the plug in the medicine bottle to move forward and administer medicine, and the drive mechanism 500 cooperates with the connecting sleeve 200 to form an injection sound structure, that is, the injection sound structure will continuously emit sound for prompting during the process of injection and administration of the drive mechanism 500;

[0055] Specifically, the insulin injection pen has a dose adjustment state and an injection state, and the insulin injection pen is converted between the dose adjustment state and the injection state by the up-down clutching of the transmission tube 420, and when converted into the injection state, the drive mechanism 500 can be used for injection and administration.

[0056] ​It should be noted that the main body shell 100, the connecting sleeve 200 and the medicine bin 300 are each injection molded. Since the driving mechanism 500 is pushed forward to move the inner plug of the medicine bottle during the dispensing process, the medicine bottle will give a reaction force to the driving mechanism 500. At this time, the injection structure is also subjected to force. The injection molded plastic part will have a problem of poor reliability under long-term stress.

[0057] To solve the above problems, the connecting sleeve 200 in the embodiment is made of a plastic part with high hardness. Even if the medicine bottle gives a reaction force to the driving mechanism 500 during injection, it will not affect the fitting accuracy between the driving mechanism 500 and the connecting sleeve 200. Therefore, the structural reliability of the insulin injection pen at this position is improved.

[0058] In addition, the connecting sleeve 200 is connected with the main body shell 100 and the medicine bin 300, which can further improve the connection stability of the main body shell 100 and the medicine bin 300. Since the sound of injection is related to the hardness of the material, the connecting sleeve 200 with high hardness can provide clearer sound between the driving mechanism 500 and the injection sound structure.

[0059] Preferably, the transmission pipe 420 has a clutch surface for clutch connection with the dose drum 410. The clutch surface has downward protruding dose drum engagement teeth 421, and the dose drum 410 has upward protruding transmission pipe matching teeth 411. Wherein,

[0060] During dose adjustment, the dose drum engagement teeth 421 are separated from the transmission pipe matching teeth 411. At this time, with the rotation of the dose drum 410, the transmission pipe 420 jumps up and down, and since the transmission pipe 420 is supported on the dose drum 410, when the dose drum 410 moves up and down along the threads of the main body shell 100, the transmission pipe 420 is driven to move up and down synchronously.

[0061] During the injection action, the transmission pipe 420 is directly pressed down by the injection button 600, and the dose drum engagement teeth 421 are engaged with the transmission pipe matching teeth 411. At this time, the transmission pipe 420 and the dose drum 410 rotate synchronously.

[0062] To better provide feedback during dose adjustment, an adjustment sound ring 430 is also provided. The adjustment sound ring 430 is located in the accommodation space between the top of the dose drum 410 and the transmission pipe 420 and is sleeved on the transmission pipe 420. The adjustment sound ring 430 and the dose drum 410 cooperate to form a forward adjustment sound structure, and the adjustment sound ring 430 and the transmission pipe 420 cooperate to form a reverse adjustment sound structure.

[0063] Specifically, the inner wall of the dose drum 410 is provided with the first ratchet 412 arranged in a one-way skewing manner, and the outer wall of the sound adjusting ring 430 is provided with the first elastic tooth 431 protruding outward, the first elastic tooth 431 is buckled with the first ratchet 412 and forms a forward sound adjusting structure.

[0064] Preferably, the outer wall of the transmission pipe 420 is provided with the second ratchet 422 arranged in a one-way skewing manner in the opposite direction of the first ratchet 412, and the inner wall of the sound adjusting ring 430 is provided with the second elastic tooth 432 protruding inward, the second elastic tooth 432 is buckled with the second ratchet 422 and forms a reverse sound adjusting structure.

[0065] That is to say, the outer wall and the inner wall of the sound adjusting ring 430 are respectively integrated with the first elastic tooth 431 and the second elastic tooth 432, and during the dose adjustment process, since the clutch surface of the transmission pipe 420 and the dose drum 410 are in a relative separation state, with the rotation of the dose drum 410, the transmission pipe 420 only jumps up and down all the time, and does not rotate with it;

[0066] Specifically, during the forward rotation of the dose drum 410, the transmission pipe 420 does not rotate, and when the surface where the first ratchet 412 is located rotates, the second ratchet 422 limits the second elastic tooth 432 to rotate, thereby the first ratchet 412 and the first elastic tooth 431 can contact to sound;

[0067] Conversely, when the dose drum 410 rotates reversely, the first ratchet 412 limits the first elastic tooth 431, at this time, the dose drum 410 drives the sound adjusting ring 430 to rotate, and the transmission pipe 420 does not rotate, and the second ratchet 422 and the second elastic tooth 432 can contact to sound.

[0068] Therefore, only one part of the sound adjusting ring 430 is needed to realize the sound problem of the forward rotation and the reverse rotation of the dose drum 410, which optimizes the overall structure, simplifies the number of parts, and makes the overall structure more reliable.

[0069] Preferably, the driving mechanism 500 includes a driving pipe 510 arranged in the transmission pipe 420, the inner wall of the transmission pipe 420 is provided with a guide rib 423 along the axial direction, and the outer wall of the driving pipe 510 is provided with a guide groove 511, and the guide rib 423 is embedded in the guide groove 511;

[0070] That is to say, through the cooperation of the guide rib 423 and the guide groove 511, the transmission pipe 420 and the driving pipe 510 can only rotate synchronously, but the transmission pipe 420 can move up and down in a linear direction along the guide rib 423, that is, during the dose adjustment process, the transmission pipe 420 moves up and down along the direction of the guide rib 423.

[0071] Further, the driving mechanism 500 further comprises a screw rod 520, which is arranged in the driving pipe 510, the cross section of the inner wall of the driving pipe 510 and the cross section of the screw rod 520 are both arranged in a waist drum shape and are connected in cooperation, through the cooperation of the waist drum shapes, the screw rod 520 and the driving pipe 510 can only rotate synchronously, that is, the transmission pipe 420, the driving pipe 510 and the screw rod 520 form a linkage structure rotating synchronously.

[0072] Preferably, the connecting sleeve 200 is provided with an integrally connected threaded seat 210, the screw rod 520 passes through the threaded seat 210 and is threadedly connected therebetween, and the end of the screw rod 520 close to the cartridge 300 passes through the threaded seat 210 and is connected with a piston push piece 521.

[0073] Preferably, the injection button 600 is further included, which is buckled with the end of the dose drum 410 away from the cartridge 300, and the transmission pipe 420 is pressed downward by pressing the injection button 600.

[0074] Specifically, when the injection action is performed, the transmission pipe 420 is directly pressed downward by the injection button 600, so that the clutch surface of the transmission pipe 420 is engaged with the dose drum 410, at this time, the dose drum 410 is rotated and lowered along the thread of the main body shell 100, thereby driving the transmission pipe 420 to rotate and lower synchronously, and since the transmission pipe 420, the driving pipe 510 and the screw rod 520 can only rotate synchronously, the screw rod 520 can extend downward along the threaded seat 210 and push the piston push piece 521 forward, thereby achieving the purpose of injection.

[0075] It is worth mentioning here that the injection button 600 directly contacts and presses the transmission pipe 420, and no transition piece is needed between them, and the adjusting sound ring 430 will not be deformed or the matching precision will not be reduced due to the pressure generated when the injection button 600 is pressed, thereby ensuring that the adjusting sound ring 430 will not be accidentally pulled out during the up-and-down movement of the transmission pipe 420, and enhancing the reliability of the adjusting sound structure.

[0076] Preferably, the inner wall of the connecting sleeve 200 is further provided with at least a pair of arc-shaped baffles 220, which are spaced apart from the threaded seat 210 and form a rotating space, wherein,

[0077] The arc-shaped baffle 220 is provided with a limiting protrusion 221, and the end of the driving pipe 510 is provided with a limiting baffle 512 arranged in a ring shape. The limiting baffle 512 is located in the rotating space between the arc-shaped baffle 220 and the threaded seat 210, and the limiting protrusion 221 is buckled with the limiting baffle 512 upward and downward, that is, the limiting protrusion 221 arranged on the driving pipe 510 plays a limiting role in the axial direction, so as to ensure that the driving pipe 510 always remains in place during the injection process, and the screw rod 520 gradually extends forward and pushes the plug in the medicine bottle through the piston push piece 521.

[0078] In addition, it should be noted that the threaded seat 210, the arc-shaped baffle 220 and the limiting protrusion 221 are integrally arranged on the connecting sleeve 200, so as to meet the linkage purpose of the driving pipe 510 and the screw rod 520, without the need to add additional parts, thereby further improving the convenience of product assembly and the reliability during use.

[0079] Preferably, the inner wall of the connecting sleeve 200 is provided with a third thorn 230, and the driving pipe 510 is provided with a third elastic tooth 513 protruding outward. The third thorn 230 and the third elastic tooth 513 cooperate to form an injection sound generating structure.

[0080] Specifically, during the injection operation, with the in-place rotation of the driving pipe 510, the third elastic tooth 513 can be moved along the third thorn 230, so as to achieve the purpose of injection sound generation.

[0081] Moreover, since the third elastic tooth 513 is integrated on the outer wall of the driving pipe 510, during assembly, it can be clearly seen whether the third elastic tooth 513 and the third thorn 230 are matched in place, and the problem of damage to the third elastic tooth 513 due to blocked vision during assembly can be avoided.

[0082] Preferably, the memory ring 530 is further arranged, which is sleeved on the driving pipe 510 and is threadedly connected therebetween. During the injection operation, with the in-place rotation of the driving pipe 510, the memory ring 530 moves upward along the driving pipe 510 and memorizes the single-dose medicine dose. The up-and-down stroke of the memory ring 530 is determined by the stop position on the driving pipe 420 and the stop position in the inner hole of the dose rotating cylinder 410.

[0083] In addition, the medicine bin 300 is further provided with a pen cap 310, which is buckled with the connecting sleeve 200.

[0084] The technical means disclosed in the utility model scheme is not limited to the technical means disclosed in the above technical means, and also includes a technical scheme composed of any combination of the above technical features. The above is the specific embodiment of the utility model, and it should be pointed out that, for ordinary technical personnel in the technical field, some improvements and decorations can be made without departing from the principle of the utility model, and these improvements and decorations are also regarded as the protection scope of the utility model.

[0085] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the utility model are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly.

[0086] In addition, the description of "first", "second", "one" and the like in the utility model is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the utility model, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited. The terms "connection", "fixation" and the like should be understood broadly, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through intermediate medium, can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For ordinary technical personnel in the art, the specific meaning of the above terms in the utility model can be understood according to the specific situation.

[0087] The technical solutions of each embodiment of the utility model can be combined with each other, but it must be based on the realization of ordinary technical personnel in the art, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the utility model.

[0088] The specific embodiments described herein are only illustrative of the spirit of the utility model. Those skilled in the art to which the utility model belongs can make various modifications or supplements to the described specific embodiments or replace them with similar ways, but without departing from the spirit of the utility model or exceeding the scope defined by the appended claims.

Claims

1. An insulin injection pen, characterized in that, include: The main body shell, the connecting sleeve, and the medicine compartment are connected by the connecting sleeve, and the medicine compartment is used to install medicine bottles. The adjustment mechanism includes a dose rotating cylinder and a transmission tube. The dose rotating cylinder is disposed inside the main body housing and the two are threadedly connected. The transmission tube is disposed inside the dose rotating cylinder and the two are engaged or disengaged. A drive mechanism is disposed inside the transmission tube. The drive mechanism is used to push the stopper inside the medicine bottle forward and administer the medicine. The drive mechanism cooperates with the connecting sleeve to form an injection sound-generating structure. The insulin pen switches from dosage adjustment to injection mode by engaging and disengaging the upper and lower clutches of the transmission tube, and the drug is injected via the drive mechanism.

2. The insulin injection pen according to claim 1, characterized in that, The transmission tube has a engagement surface for disengaging with the dosing cylinder, the engagement surface having downwardly protruding dosing cylinder engagement teeth, while the dosing cylinder has upwardly protruding transmission tube engagement teeth. During the dosage adjustment process, the meshing teeth of the dosage drum separate from the meshing teeth of the transmission tube. At this time, as the dosage drum rotates, the transmission tube jumps up and down. During the injection process, the transmission tube is pressed down directly by pressing the injection button, causing the meshing teeth of the dosage drum to mesh with the teeth of the transmission tube. At this time, the transmission tube and the dosage drum rotate synchronously.

3. An insulin injection pen according to claim 1, characterized in that, The driving mechanism includes a driving tube disposed inside the transmission tube. The inner wall of the transmission tube is provided with guide ribs along its axial direction, and the outer wall of the driving tube is provided with a guide groove, in which the guide ribs are embedded.

4. An insulin injection pen according to claim 3, characterized in that, The driving mechanism also includes a screw, which is disposed inside the driving tube. The cross-section of the inner wall of the driving tube and the cross-section of the screw are both arranged in a waist-drum shape and are connected together.

5. An insulin injection pen according to claim 4, characterized in that, The connecting sleeve is provided with an integrally connected threaded seat, the screw passes through the threaded seat and the two are threadedly connected, and the end of the screw near the medicine tank passes through the threaded seat and is connected to a piston pusher.

6. An insulin injection pen according to claim 5, characterized in that, The inner wall of the connecting sleeve is also provided with at least one pair of arc-shaped baffles. There is a distance between the arc-shaped baffles and the threaded seat to form a rotation space. The arc-shaped baffles have a limiting protrusion. The end of the drive tube is provided with a ring-shaped limiting stop. The limiting stop is located in the rotation space between the arc-shaped baffles and the threaded seat. The limiting protrusion and the limiting stop are engaged vertically.

7. An insulin injection pen according to claim 1, characterized in that, It also includes an adjusting sound-emitting ring, which is located in the receiving space between the top of the dose rotating cylinder and the transmission tube and is sleeved on the transmission tube. The adjusting sound-emitting ring and the dose rotating cylinder cooperate to form a positive adjusting sound-emitting structure, and the adjusting sound-emitting ring and the transmission tube cooperate to form a reverse adjusting sound-emitting structure.

8. An insulin injection pen according to claim 7, characterized in that, The inner wall of the dosing cylinder is provided with a first thorn that is unidirectionally oblique, and the outer wall of the adjusting sound ring is provided with a first elastic tooth that protrudes outward. The first elastic tooth is engaged with the first thorn to form the positive adjusting sound structure.

9. An insulin injection pen according to claim 8, characterized in that, The outer wall of the transmission tube is provided with a second thorn, which is unidirectionally deflected in the opposite direction to the first thorn. The inner wall of the adjusting sound ring is provided with an inwardly protruding second elastic tooth, which is engaged with the second thorn to form the reverse adjusting sound structure.

10. An insulin injection pen according to claim 3, characterized in that, The inner wall of the connecting sleeve is provided with a third thorn, and the driving tube is provided with a third elastic tooth protruding outward. The third thorn and the third elastic tooth cooperate to form the injection sound-generating structure.

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