An injection pen

Abstract

The application relates to the technical field of medical devices, in particular to an injection pen, which comprises a main shell part, an operation part which is partially installed in the interior of the main shell part in a circumferential limiting mode and is movable in an axial direction, a dose setting part which is in threaded connection with the operation part and is in axial limiting connection with the main shell part and is movable in a circumferential direction, a driving rod part which is provided with a first one-way limiting structure between the main shell part and the operation part and is provided with a second one-way limiting structure between the dose setting part, the driving rod part and the main shell part are relatively static in the state that the operation part moves towards a proximal end, the driving rod part and the dose setting part rotate synchronously in the state that the operation part moves towards a distal end, a screw rod part which passes through the interior of the driving rod, one of the main shell part and the driving rod part is in threaded connection with the screw rod part, and the other is in circumferential limiting connection with the screw rod part and is movable in an axial direction. The application realizes dose setting and injection through the push-pull action of the operation part, and solves the problem that the dose setting and injection operation is complex.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to an injection pen. BACKGROUND

[0002] In the related art, the operation of setting dose and injection is relatively complex when the injection pen is used in a single fixed dose injection environment. SUMMARY

[0003] The present application aims to provide an injection pen to solve the problem of complex operation of setting dose and injection. The specific scheme is as follows:

[0004] An injection pen comprises:

[0005] a main housing portion;

[0006] an operation portion, part of which is installed in the interior of the main housing portion in circumferential limiting manner and is movable in a preset range in axial direction;

[0007] a dose setting portion, which is threadedly connected with the operation portion and axially limitedly connected with the main housing portion and is movable in circumferential direction;

[0008] a drive rod portion, which is provided with a first one-way limiting structure between the drive rod portion and the main housing portion and a second one-way limiting structure between the drive rod portion and the dose setting portion, so that the drive rod portion and the main housing portion are relatively stationary in the state that the operation portion moves toward the proximal end of the injection pen, and the drive rod portion and the dose setting portion rotate synchronously in the state that the operation portion moves toward the distal end of the injection pen;

[0009] a screw rod portion, which passes through the interior of the drive rod portion, one of the main housing portion and the drive rod portion is threadedly connected with the screw rod portion, and the other of the main housing portion and the drive rod portion is circumferentially limitedly connected with the screw rod portion and is movable in axial direction.

[0010] Optionally, the first one-way limiting structure comprises first one-way clamping grooves distributed in circumferential direction on one of the drive rod portion and the main housing portion, and a first elastic clamping portion on the other of the drive rod portion and the main housing portion, which is clamped into any of the first one-way clamping grooves;

[0011] In the state that the operation portion moves toward the proximal end of the injection pen, the first elastic clamping portion and the circumferential wall surrounding the first one-way clamping groove abut to realize circumferential limiting; in the state that the operation portion moves toward the distal end of the injection pen, the first elastic clamping portion slides along the circumferential wall surrounding the first one-way clamping groove to be clamped into the first one-way clamping groove at the front end.

[0012] Optionally, the second one-way limiting structure comprises a second one-way clamping groove arranged in one of the driving rod part and the dose setting part and distributed in the circumference, and a second elastic clamping part arranged in the other of the driving rod part and the dose setting part, the second elastic clamping part clamping into any of the second one-way clamping grooves;

[0013] In the state that the operation part moves towards the proximal end of the injection pen, the second elastic clamping part slides along the circumferential wall surrounding the second one-way clamping groove to clamp into one of the second one-way clamping grooves at the front end; in the state that the operation part moves towards the distal end of the injection pen, the second elastic clamping part and the circumferential wall surrounding the second one-way clamping groove abut to achieve circumferential limiting.

[0014] Optionally, the main housing part comprises an outer housing part and a bottle holder cover part, the outer housing part and the bottle holder cover part are independent structures and are fixedly connected in a mechanical manner, the bottle holder cover part is provided with one of the first elastic clamping part and the first one-way clamping groove, the bottle holder cover part and the screw rod part are threadedly connected, or the bottle holder cover part and the screw rod part are circumferentially limitedly connected and axially movable.

[0015] Optionally, one of the dose setting part and the operation part is provided with a helical protrusion, and the other is provided with a helical groove, the helical protrusion is embedded in the inside of the helical groove, the proximal end of the helical groove is a closed end, and in the state that the proximal end wall of the helical protrusion and the proximal end wall of the helical groove abut, the operation part moves towards the proximal end of the injection pen to the limit position.

[0016] Optionally, the dose setting part comprises a scale disc and a fixed clamp, the scale disc and the fixed clamp are independent structures and are fixedly connected in a mechanical manner, the scale disc is provided with one of the helical protrusion and the helical groove, and the fixed clamp and the main housing part are axially limitedly connected and circumferentially movable.

[0017] Optionally, one of the operation part and the dose setting part is provided with a blocking part, and the other is provided with a blocking groove, in the state that the blocking part is sunk into the blocking groove to fix the operation part and the dose setting part relative to each other, the operation part moves towards the distal end of the injection pen to the limit position.

[0018] Optionally, the injection pen further comprises a rotating wheel, the rotating wheel is sleeved with the driving rod part and is circumferentially limitedly connected and axially movable, the rotating wheel and the dose setting part are threadedly connected, the driving rod part has a stop part configured to abut with the rotating wheel to limit the limit position of the rotating wheel moving towards the proximal end of the injection pen.

[0019] Optionally, the injection pen further comprises a bottle support part, the main housing part and the bottle support part are threadedly connected, the injection pen further comprises a medicine bottle, the medicine bottle is installed on the bottle support part, the inside of the medicine bottle is provided with a sealing plug, the screw rod part extends into the inside of the medicine bottle, the bottle support part has a pre-assembly position and a working position and can move from the pre-assembly position to the working position, wherein:

[0020] In the pre-assembly position, there is a gap between the screw rod part and the sealing plug, the sealing plug is in a first position; in the working position, the screw rod part abuts against the sealing plug, the sealing plug is in a second position, the second position is closer to the distal end of the medicine bottle than the first position.

[0021] Optionally, one of the main housing part and the bottle support part is provided with an elastic clamping part, the other is provided with a first hole part and a second hole part, in the pre-assembly position, the elastic clamping part and the first hole part are clamped and matched; in the working position, the elastic clamping part and the second hole part are clamped and matched.

[0022] When the injection pen of the present application sets the dose, the operator pulls the operation part towards the proximal end of the injection pen, the operation part drives the dose setting part to rotate circumferentially through threaded transmission, under the action of the first one-way limiting structure and the second one-way limiting structure, the driving rod part remains relatively static with the main housing part, that is, the movement of the operation part towards the proximal end of the injection pen does not drive the driving rod part to act, the screw rod part remains static due to the static driving rod part, through the corresponding relationship between the rotation amount of the dose setting part and the axial displacement amount of the operation part, the setting of the target dose is completed; after the dose setting is completed, the operator pushes the operation part towards the distal end of the injection pen, the operation part drives the dose setting part to reversely rotate circumferentially through threaded transmission, under the action of the first one-way limiting structure and the second one-way limiting structure, the driving rod part rotates synchronously with the dose setting part, the screw rod part moves axially towards the distal end, the screw rod part can push the sealing plug in the medicine bottle to move towards the distal end, when the operation part moves to the limit position towards the distal end of the injection pen, the set dose of liquid medicine is discharged, the injection is completed. It can be seen that the injection pen of the present application can realize the setting of the dose and the injection only through the push-pull action of the operation part, significantly simplifying the dose setting and injection operation, effectively solving the problem of complex dose setting and injection operation in the related art. At the same time, the cooperation of the first one-way limiting structure and the second one-way limiting structure ensures that the screw rod part is static during dose setting and acts during injection, avoiding the misdischarge of liquid medicine during the dose setting stage, avoiding the occurrence of dose deviation, and improving the dose accuracy; the threaded connection transmission mode between the dose setting part and the operation part, and between one of the main housing part and the driving rod part and the screw rod part, is beneficial to improving the accuracy of dose setting, thereby ensuring the controllability of the dose. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 This is a breakdown diagram of a specific embodiment of the injection pen provided in this application;

[0024] Figure 2 for Figure 1 Axial sectional view of the injection pen in its assembled state;

[0025] Figure 3 for Figure 1 Another axial sectional view of the injection pen in its assembled state;

[0026] Figure 4 for Figure 1 A schematic diagram of the drive lever and bottle holder cap in an injection pen;

[0027] Figure 5 for Figure 1 A schematic diagram of the drive lever and dosage setting part in an injection pen;

[0028] Figure 6 for Figure 1 A schematic diagram of the bottle holder cap in an injection pen;

[0029] Figure 7 for Figure 1 A partial sectional view of the main housing of the injection pen;

[0030] Figure 8 for Figure 1 A partial sectional view of the bottle holder cap and main housing of an injection pen in the assembled state;

[0031] Figure 9 for Figure 1 A schematic diagram of the bottle holder cap and screw in the assembled state of an injection pen;

[0032] Figure 10 for Figure 1 A schematic diagram of the drive rod and screw section of an injection pen in their assembled state;

[0033] Figure 11 for Figure 1 A schematic diagram of the separate structure of the main shell and the operating part in an injection pen;

[0034] Figure 12 for Figure 1 A schematic diagram of the dosage setting section in an injection pen;

[0035] Figure 13 for Figure 1 A schematic diagram of the operating section in an injection pen;

[0036] Figure 14 for Figure 1 A partial sectional view of the dial and sleeve of the injection pen in the assembled state;

[0037] Figure 15 for Figure 12 A schematic diagram of the middle dial;

[0038] Figure 16 for Figure 12 A schematic diagram of the structure of the fixing clip;

[0039] Figure 17 for Figure 12 A partial sectional view;

[0040] Figure 18 for Figure 1 A partial cross-sectional view of the main housing and dosage setting section of the injection pen in the assembled state;

[0041] Figure 19 for Figure 1 Another partial cross-sectional view of the main housing of the injection pen;

[0042] Figure 20 for Figure 19 A partial sectional view of the middle and outer shell sections;

[0043] Figure 21 for Figure 17 Schematic diagram of the middle fixing ring;

[0044] Figure 22 for Figure 1 A breakdown diagram of the tail cap and dosage setting section of an injection pen;

[0045] Figure 23 for Figure 1 A schematic diagram of the tail cap and dosage setting part when the operating part of the injection pen is moved to the extreme position towards the distal end of the injection pen;

[0046] Figure 24 for Figure 1 A partial cross-sectional view of the rotary wheel, drive lever, and dosage setting unit of the injection pen in its assembled state;

[0047] Figure 25 for Figure 1 A schematic diagram of the rotating wheel and drive rod in the assembled state of an injection pen;

[0048] Figure 26 for Figure 3 Enlarged view of region A in the middle;

[0049] Figure 27 for Figure 1 A magnified view of the support section of the syringe pen in its pre-assembly position;

[0050] Figure 28 for Figure 1 A magnified view of the support section of the syringe pen in its working position;

[0051] Figure 29 For Figure 1 Structure diagram of the connection between the main housing part and the bottle support part in the injection pen;

[0052] Wherein, the reference signs are as follows:

[0053] 100 - main housing part;

[0054] 100-1 - outer housing part; 100-11 - barrel part; 100-12 - end plate part;

[0055] 100-2 - bottle support cover part; 100-A - fixing groove part; 100-B - abutting wall part; 100-C - fixing convex part; 100-D - convex rib part; 100-E - recessed part;

[0056] 100-3 - fixing ring part; 100-31 - connecting arm; 100-32 - stepped wall part;

[0057] 101 - operation part; 101-1 - sleeve part; 101-2 - tail cover part;

[0058] 102 - dose setting part; 102-1 - dial; 102-2 - fixing clamp; 102-A - fixing protrusion; 102-B - fixing hole; 102-C - limiting convex rib; 102-D - limiting groove; 102-E - stepped part;

[0059] 103 - drive rod part; 103-A - stop part;

[0060] 104 - first one-way limiting structure; 104-1 - first one-way clamping groove; 104-2 - first elastic clamping part;

[0061] 105 - second one-way limiting structure; 105-1 - second one-way clamping groove; 105-2 - second elastic clamping part;

[0062] 106 - screw rod part;

[0063] 107 - limiting protrusion; 108 - limiting groove;

[0064] 109 - clamping protrusion; 110 - clamping hole;

[0065] 111 - helical convex strip; 112 - helical groove;

[0066] 113 - annular clamping groove; 114 - protrusion part;

[0067] 115 - abutting wall; 116 - first end wall; 117 - convex part; 118 - second end wall;

[0068] 119 - fixing groove; 120 - first limiting wall; 121 - second limiting wall;

[0069] 122 - blocking part; 123 - blocking groove;

[0070] 124 - rotating wheel;

[0071] 125 - bottle support part;

[0072] 126 - elastic clamping part; 127 - first hole part; 128 - second hole part;

[0073] 129 - indication mark;

[0074] 130 - shell cover part; 131 - screw gasket;

[0075] 001 - medicine bottle; 002 - sealing plug; DETAILED DESCRIPTION

[0076] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0077] The terms "first", "second", and the like in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be exchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally a class, and are not limited to the number of objects, for example, the first object can be one or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / ", generally indicates that the front and rear associated objects are in an "or" relationship.

[0078] It should be understood that the "some embodiments" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiments are included in at least one embodiment of the present application. Therefore, "in some embodiments" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner.

[0079] In the description herein, unless specifically defined and limited otherwise, the terms "connected", "connected", "fixed" should be understood broadly, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in this paper can be understood according to the specific circumstances.

[0080] Definition: when the operator operates the injection pen, the injection pen is located between the operator and the injection site, wherein the end of the injection pen and other components in the injection pen close to the operator is the proximal end, and the end close to the injection site is the distal end.

[0081] Please refer to Figures 1-5 , Figure 1 The exploded view of a specific embodiment of the injection pen provided in the present application; Figure 2 The axial sectional view of the injection pen in the assembled state; Figure 1 The axial sectional view of the injection pen in the assembled state; Figure 3 The axial sectional view of the injection pen in the assembled state; Figure 1 The structure diagram of the driving rod part and the bottle cover part in the injection pen; Figure 4 The structure diagram of the driving rod part and the dose setting part in the injection pen. Figure 1 Figure 5 The structure diagram of the driving rod part and the dose setting part in the injection pen. Figure 1 The injection pen provided by the embodiment of the present application comprises:

[0082] The main shell part 100;

[0083] The operation part 101 is partially installed in the interior of the main shell part 100 in the circumferential direction and is movable in the axial direction within a preset range;

[0084] The dose setting part 102 is threadedly connected with the operation part 101, and the dose setting part 102 is axially limitedly connected with the main shell part 100 and is movable in the circumferential direction;

[0085] The driving rod part 103 is provided with the first one-way limiting structure 104 between the driving rod part 103 and the main shell part 100, and the second one-way limiting structure 105 between the driving rod part 103 and the dose setting part 102, so that in the state that the operation part 101 moves towards the proximal end of the injection pen, the driving rod part 103 and the main shell part 100 are relatively static, and in the state that the operation part 101 moves towards the distal end of the injection pen, the driving rod part 103 and the dose setting part 102 rotate synchronously;

[0086]

[0087] ​​The screw rod part 106 passes through the inside of the driving rod part 103, one of the main housing part 100 and the driving rod part 103 and the screw rod part 106 are threadedly connected, and the other of the main housing part 100 and the driving rod part 103 and the screw rod part 106 are circumferentially limitedly connected and axially movable.

[0088] The steps of the injection pen in the dose setting process are as follows:

[0089] The operator pulls the operation part 101 towards the proximal end of the injection pen, and the operation part 101 drives the dose setting part 102 to rotate along the circumference through the threaded transmission. Under the action of the first one-way limiting structure 104 and the second one-way limiting structure 105, the driving rod part 103 remains relatively static with the main housing part 100, that is, the movement of the operation part 101 towards the proximal end of the injection pen does not drive the driving rod part 103 to move. The screw rod part 106 remains static due to the static driving rod part 103. Through the corresponding relationship between the rotation amount of the dose setting part 102 and the axial displacement amount of the operation part 101, the setting of the target dose is completed.

[0090] The steps of the injection pen in the injection process are as follows:

[0091] After the dose setting is completed, the operator pushes the operation part 101 towards the distal end of the injection pen, and the operation part 101 drives the dose setting part 102 to reversely rotate along the circumference through the threaded transmission. Under the action of the first one-way limiting structure 104 and the second one-way limiting structure 105, the driving rod part 103 rotates along the circumference synchronously with the dose setting part 102. Since the screw rod part 106 passes through the inside of the driving rod part 103, one of the main housing part 100 and the driving rod part 103 and the screw rod part 106 are threadedly connected, and the other of the main housing part 100 and the driving rod part 103 and the screw rod part 106 are circumferentially limitedly connected and axially movable, specifically: if the driving rod part 103 and the screw rod part 106 are threadedly connected, the main housing part 100 and the screw rod part 106 are circumferentially limitedly connected and axially movable, then the rotation of the driving rod part 103 drives the screw rod part 106 to move axially towards the distal end through the threaded transmission; if the main housing part 100 and the screw rod part 106 are threadedly connected, the driving rod part 103 and the screw rod part 106 are circumferentially limitedly connected and axially movable, then the rotation of the driving rod part 103 drives the screw rod part 106 to rotate synchronously, and then drives the screw rod part 106 to move axially towards the distal end through the threaded cooperation with the main housing part 100. The screw rod part 106 can push the sealing plug 002 in the medicine bottle 001 to move towards the distal end. When the operation part 101 moves to the limit position towards the distal end of the injection pen, the set dose of the liquid medicine is discharged, and the injection is completed.

[0092] It can be seen that the injection pen of the embodiment of the application can realize dose setting and injection only by the pushing and pulling action of the operation part 101, significantly simplifies the dose setting and injection operation, and effectively solves the problem of complex dose setting and injection operation in the related art. Meanwhile, the cooperation of the first one-way limiting structure 104 and the second one-way limiting structure 105 ensures that the screw rod part 106 is static during dose setting and moves during injection, avoids the mis-discharge of the drug liquid during the dose setting stage, avoids causing dose deviation, and improves the dose accuracy; the transmission mode of the threaded connection between the dose setting part 102 and the operation part 101, one of the main shell part 100 and the drive rod part 103 and the screw rod part 106 is beneficial to improve the accuracy of dose setting, thereby ensuring the controllability of the dose.

[0093] Please continue to refer to Figure 4 In the embodiment of the application, the first one-way limiting structure 104 includes the first one-way clamping groove 104-1 arranged on one of the drive rod part 103 and the main shell part 100 and distributed in the circumferential direction, and the first elastic clamping part 104-2 arranged on the other one of the drive rod part 103 and the main shell part 100, the first elastic clamping part 104-2 is clamped into any first one-way clamping groove 104-1.

[0094] In the state that the operation part 101 moves towards the proximal end of the injection pen, the first elastic clamping part 104-2 and the circumferential wall surrounding the first one-way clamping groove 104-1 abut to realize circumferential limiting; in the state that the operation part 101 moves towards the distal end of the injection pen, the first elastic clamping part 104-2 slides along the circumferential wall surrounding the first one-way clamping groove 104-1 to be clamped into one of the first one-way clamping grooves 104-1 at the front end.

[0095] As set forth above, in the dose setting stage, the first elastic clamping portion 104-2 and the circumferential wall surrounding the first one-way clamping groove 104-1 abut to achieve circumferential limiting, so that the driving rod portion 103 and the main housing portion 100 remain relatively static, ensuring that the screw rod portion 106 is static during dose setting, avoiding the initiation of dose deviation, and improving dose accuracy; in the injection stage, the first elastic clamping portion 104-2 can slide along the circumferential wall surrounding the first one-way clamping groove 104-1 to clamp into one of the first one-way clamping grooves 104-1 at the front end, where the front end refers to the end pointed by the sliding direction of the first elastic clamping portion 104-2, avoiding the interference of the main housing portion 100 with the rotation of the driving rod portion 103, and ensuring the normal operation of the injection action. In the process of the first elastic clamping portion 104-2 gradually sliding out of the current first one-way clamping groove 104-1, the first elastic clamping portion 104-2 is deformed under compression, and the first elastic clamping portion 104-2 gradually accumulates energy; when the first elastic clamping portion 104-2 passes the current first one-way clamping groove 104-1, the elastic potential energy of the first elastic clamping portion 104-2 is released, and the first elastic clamping portion 104-2 is instantly snapped into the next first one-way clamping groove 104-1. The impact of the first elastic clamping portion 104-2 and the circumferential wall surrounding the first one-way clamping groove 104-1 will produce a "click" sound, or cause a slight vibration of the injection pen. Through the impact sound or vibration, the user can be prompted about the current operation state, and the use safety is improved.

[0096] Please continue to refer to Figure 5 In the embodiments of the present application, the second one-way limiting structure 105 includes a second one-way clamping groove 105-1 arranged on one of the driving rod portion 103 and the dose setting portion 102 and distributed circumferentially, and a second elastic clamping portion 105-2 arranged on the other of the driving rod portion 103 and the dose setting portion 102, the second elastic clamping portion 105-2 clamping into any second one-way clamping groove 105-1;

[0097] In the state that the operation portion 101 moves towards the proximal end of the injection pen, the second elastic clamping portion 105-2 slides along the circumferential wall surrounding the second one-way clamping groove 105-1 to clamp into one of the second one-way clamping grooves 105-1 at the front end; in the state that the operation portion 101 moves towards the distal end of the injection pen, the second elastic clamping portion 105-2 and the circumferential wall surrounding the second one-way clamping groove 105-1 abut to achieve circumferential limiting.

[0098] As set forth above, during the dose setting stage, the second elastic clamping portion 105-2 slides along the circumferential wall of the second one-way clamping groove 105-1 to be clamped into one of the second one-way clamping grooves 105-1 at the front end, where the front end refers to the end pointed by the sliding direction of the second elastic clamping portion 105-2, to avoid interference of the rotation of the dose setting portion 102 by the driving rod portion 103, so that the dose setting portion 102 can be circumferentially rotated with the axial movement of the operation portion 101 to complete dose setting; during the process that the second elastic clamping portion 105-2 gradually slides out of the current second one-way clamping groove 105-1, the second elastic clamping portion 105-2 is deformed by extrusion, and the second elastic clamping portion 105-2 gradually stores energy; when the second elastic clamping portion 105-2 passes the current second one-way clamping groove 105-1, the elastic potential energy of the second elastic clamping portion 105-2 is released, and the second elastic clamping portion 105-2 is instantly elastically clamped into the next second one-way clamping groove 105-1, and the impact between the second elastic clamping portion 105-2 and the circumferential wall of the second one-way clamping groove 105-1 produces a "click" sound or a slight vibration of the injection pen, so that the user can be prompted about the current operation state through the impact sound or vibration, and the use safety is improved. During the injection stage, the second elastic clamping portion 105-2 and the circumferential wall of the second one-way clamping groove 105-1 abut to achieve circumferential limiting, so that the driving rod portion 103 can be synchronously rotated with the dose setting portion 102, the driving screw portion 106 pushes the liquid medicine, and the injection is completed.

[0099] In the embodiments of the present application, the first elastic clamping portion 104-2 and the second elastic clamping portion 105-2 are both made of a material capable of producing elastic deformation, such as plastic with a certain elasticity.

[0100] In the embodiments of the present application, the first elastic clamping portion 104-2 and the second elastic clamping portion 105-2 are both made of a material capable of producing elastic deformation, such as plastic with a certain elasticity. Figure 4 As can be seen, in the embodiments of the present application, the number of the first elastic clamping portion 104-2 is two, and the two first elastic clamping portions 104-2 are arranged along the circumference of the other one of the driving rod portion 103 and the main housing portion 100. The two first elastic clamping portions 104-2 are used to realize one-way locking in cooperation with the first one-way clamping groove 104-1, which is beneficial to dispersing load and improving the carrying capacity of the injection pen and the locking precision of the driving rod portion 103 and the main housing portion 100. In some other embodiments of the present application, the other one of the driving rod portion 103 and the main housing portion 100 has at least one first elastic clamping portion 104-2.

[0101] In the embodiments of the present application, the first elastic clamping portion 104-2 and the second elastic clamping portion 105-2 are both made of a material capable of producing elastic deformation, such as plastic with a certain elasticity. Figure 5It can be seen that, in the embodiment of the application, the number of the second elastic clamping portions 105-2 is two, and the two second elastic clamping portions 105-2 are arranged at intervals in the circumferential direction of the other one of the drive rod portion 103 and the dose setting portion 102, and the one-way locking is achieved by cooperation of the two second elastic clamping portions 105-2 and the second one-way clamping groove 105-1, which is beneficial to dispersing the load, improving the carrying capacity of the injection pen of the embodiment of the application, and improving the locking accuracy of the drive rod portion 103 and the dose setting portion 102. In some other embodiments of the application, the other one of the drive rod portion 103 and the dose setting portion 102 has at least one second elastic clamping portion 105-2.

[0102] By Figure 4 It can be seen that, in the embodiment of the application, one of the drive rod portion 103 and the main housing portion 100 is provided with a plurality of first ratchets distributed in the circumferential direction, and a first ratchet groove is formed between adjacent first ratchets, and the first ratchet groove is the aforementioned first one-way clamping groove 104-1.

[0103] The wall surface of the first ratchet has a blocking surface and an inclined surface. In a state in which the operation portion 101 moves toward the proximal end of the injection pen, the first elastic clamping portion 104-2 abuts against the blocking surface to achieve circumferential limiting, so that the drive rod portion 103 and the main housing portion 100 remain relatively stationary. In a state in which the operation portion 101 moves toward the distal end of the injection pen, the first elastic clamping portion 104-2 can slide along the inclined surface, so as to smoothly slide over the top end of the current first ratchet and fall into the next first ratchet groove, thereby avoiding interference of the main housing portion 100 with the rotation of the drive rod portion 103. The inclined surface can reduce the operation resistance and improve the operation convenience.

[0104] By Figure 5 It can be seen that, in the embodiment of the application, one of the drive rod portion 103 and the dose setting portion 102 is provided with a plurality of second ratchets distributed in the circumferential direction, and a second ratchet groove is formed between adjacent second ratchets, and the second ratchet groove is the aforementioned second one-way clamping groove 105-1.

[0105] Similarly, the wall surface of the second ratchet has a blocking surface and an inclined surface. In a state in which the operation portion 101 moves toward the proximal end of the injection pen, the second elastic clamping portion 105-2 can slide along the inclined surface, so as to smoothly slide over the top end of the current second ratchet and fall into the next second ratchet groove, thereby avoiding interference of the drive rod portion 103 with the rotation of the dose setting portion 102. The inclined surface can reduce the operation resistance and improve the operation convenience. In a state in which the operation portion 101 moves toward the distal end of the injection pen, the second elastic clamping portion 105-2 abuts against the blocking surface to achieve circumferential limiting, so that the drive rod portion 103 can rotate synchronously with the dose setting portion 102, the drive screw portion 106 pushes the liquid medicine, and the injection is completed.

[0106] It can be seen that the first one-way clamping groove 104-1 and the second one-way clamping groove 105-1 are obtained by designing the ratchet structure, the shape of the ratchet is relatively standard, and the ratchet is convenient to manufacture by machining, stamping, casting or injection molding, etc., thereby improving the molding convenience and reducing the production cost.

[0107] Please refer to Figures 6-8 , Figure 6 for Figure 1 the structure of the bottle rack cover part in the injection pen; Figure 7 for Figure 1 the partial cross-sectional view of the main shell part in the injection pen; Figure 8 for Figure 1 the partial cross-sectional view of the bottle rack cover part and the main shell part in the injection pen in the assembled state.

[0108] In the embodiment of the application, the main shell part 100 includes an outer shell part 100-1 and a bottle rack cover part 100-2, the outer shell part 100-1 and the bottle rack cover part 100-2 are independent structures and are fixedly connected in a mechanical manner, the bottle rack cover part 100-2 is provided with one of the first elastic clamping part 104-2 and the first one-way clamping groove 104-1, the bottle rack cover part 100-2 is threadedly connected with the screw rod part 106, or the bottle rack cover part 100-2 is circumferentially limitedly connected with the screw rod part 106 and is axially movable.

[0109] As arranged above, in the embodiment of the application, the main shell part 100 adopts the structure that the outer shell part 100-1 and the bottle rack cover part 100-2 are independently designed and mechanically fixedly connected, the outer shell part 100-1 and the bottle rack cover part 100-2 can be separately formed, the structure of the outer shell part 100-1 and the bottle rack cover part 100-2 is simpler, which is beneficial to simplify the forming process of the outer shell part 100-1 and the bottle rack cover part 100-2 and improve the forming efficiency of the outer shell part 100-1 and the bottle rack cover part 100-2.

[0110] The outer shell part 100-1 and the bottle rack cover part 100-2 are fixedly connected in a mechanical manner. In the embodiment, the outer shell part 100-1 comprises a cylinder part 100-11, the inside of the cylinder part 100-11 is hollow, and the two axial ends are open ends. The end plate part 100-12 is fixed in the inside of the cylinder part 100-11, and the end plate part 100-12 is arranged along the radial direction of the cylinder part 100-11. Among the inner wall of the outer shell part 100-1 and the outer wall of the bottle rack cover part 100-2, one has a fixed groove part 100-A arranged along the axial direction, the fixed groove part 100-A has an abutting wall part 100-B facing the end plate part 100-12, and the other has a fixed convex part 100-C. In the connected state, the fixed convex part 100-C is clamped in the inside of the fixed groove part 100-A, the wall part of the fixed convex part 100-C away from the end plate part 100-12 abuts against the abutting wall part 100-B, the end wall of the bottle rack cover part 100-2 facing the end plate part 100-12 abuts against the end plate part 100-12, and the fixed connection of the outer shell part 100-1 and the bottle rack cover part 100-2 is achieved.

[0111] In addition, among the inner wall of the outer shell part 100-1 and the outer wall of the bottle rack cover part 100-2, one is provided with a convex rib part 100-D, and the other is provided with a recessed part 100-E. In the connected state, the convex rib part 100-D is inserted into the inside of the corresponding recessed part 100-E. In this way, the outer shell part 100-1 and the bottle rack cover part 100-2 are rigidly matched through the embedded design of the convex rib part 100-D and the recessed part 100-E, so that the outer shell part 100-1 and the bottle rack cover part 100-2 are reliably constrained in the circumferential direction, and the power transmission reliability is improved.

[0112] Please refer to Figure 6 , Figure 9 and Figure 10 , Figure 9 for Figure 1 the structure schematic diagram of the bottle rack cover part and the screw rod part in the injection pen in the assembled state; Figure 10 for Figure 1 the structure schematic diagram of the driving rod part and the screw rod part in the injection pen in the assembled state.

[0113] In the embodiment, the bottle rack cover part 100-2 and the screw rod part 106 are threadedly connected, the driving rod part 103 and the screw rod part 106 are circumferentially limited and connected, and are axially movable. During injection, the driving rod part 103 drives the screw rod part 106 to rotate synchronously, and then moves the screw rod part 106 axially to the far end through the thread cooperation with the bottle rack cover part 100-2, the screw rod part 106 pushes the sealing plug 002 in the medicine bottle 001 to move to the far end, and the injection is completed.

[0114] In the embodiment, the outer peripheral wall of the screw rod part 106 comprises a first plane, the inner peripheral wall of the driving rod part 103 comprises a second plane, in the mounted state, the driving rod part 103 is sleeved outside the screw rod part 106, the first plane and the second plane are attached to each other, the first plane and the second plane form a circumferential limiting part, the circumferential limiting of the driving rod part 103 and the screw rod part 106 is guaranteed to be reliable, the processing technology of the driving rod part 103 and the screw rod part 106 is simplified, and the processing efficiency is improved.

[0115] Please refer to Figure 11 , Figure 11 For Figure 1 The schematic view of the split structure of the main housing part and the operation part in the injection pen.

[0116] As described above, the partial operation part 101 is mounted in the interior of the main housing part 100 in the circumferential limiting manner and is movable in the preset range in the axial direction. In the embodiment, one of the operation part 101 and the main housing part 100 is provided with a limiting protrusion 107 extending in the axial direction, and the other is provided with a limiting groove 108 extending in the axial direction, the limiting protrusion 107 is inserted into the interior of the corresponding limiting groove 108, the circumferential limiting of the operation part 101 and the main housing part 100 is realized, and the axial relative movement of the operation part 101 and the main housing part 100 is not interfered, the normal performance of the dose setting and the injection action is guaranteed.

[0117] By Figure 11 It can be seen that, in the embodiment, the operation part 101 comprises a sleeve part 101-1 and a tail cover part 101-2, the sleeve part 101-1 and the tail cover part 101-2 are independent structures and are connected to each other in a mechanical manner, so that the sleeve part 101-1 and the tail cover part 101-2 can be formed separately, the forming process is simplified, and the forming efficiency is improved.

[0118] In the embodiment, one of the sleeve part 101-1 and the tail cover part 101-2 is provided with a clamping protrusion 109, and the other is provided with a clamping hole 110, the clamping protrusion 109 and the clamping hole 110 are clamped and matched to realize the fixed connection of the sleeve part 101-1 and the tail cover part 101-2, while guaranteeing the reliable connection of the sleeve part 101-1 and the tail cover part 101-2, the assembly steps of the sleeve part 101-1 and the tail cover part 101-2 are simplified, and the assembly efficiency of the sleeve part 101-1 and the tail cover part 101-2 is improved.

[0119] In some other embodiments of the application, the sleeve part 101-1 and the tail cover part 101-2 can be fixed by thread connection, interference fit, etc.

[0120] Please refer to Figures 12-14 , Figure 12 For Figure 1 The schematic view of the structure of the dose setting part in the injection pen.Figure 13 As Figure 1 Structure diagram of the operation part in the injection pen; Figure 14 As Figure 1 Partial sectional view of the dial and sleeve part in the injection pen in the assembled state.

[0121] In the embodiment, one of the dose setting part 102 and the operation part 101 is provided with the helical protrusion 111, and the other is provided with the helical groove 112. The helical protrusion 111 is embedded in the interior of the helical groove 112. The proximal end of the helical groove 112 is a closed end. In the state that the proximal end wall of the helical protrusion 111 and the proximal end wall of the helical groove 112 abut, the operation part 101 moves to the limit position towards the proximal end of the injection pen.

[0122] As above, in the process of setting the dose, when the proximal end wall of the helical protrusion 111 and the proximal end wall of the helical groove 112 abut, the operation part 101 cannot continue to move towards the proximal end of the injection pen, indicating that the current set dose has reached the maximum value. It can be seen that the proximal end wall of the helical groove 112 defines the end point of each dose setting and the starting point of each injection. This mechanical limiting method is beneficial to improve the accuracy of dose setting and thus improve the consistency of each injection dose. Moreover, when the proximal end wall of the helical protrusion 111 and the proximal end wall of the helical groove 112 abut, the operator will feel obvious resistance when continuing to pull the operation part 101. The operator does not need to read the complex scale to determine that the operation part 101 has reached the set end point, which improves the operation efficiency and ensures the accuracy and safety of dose setting.

[0123] In addition, the size parameters of the helical groove 112 directly determine the maximum movement stroke of the operation part 101. By adjusting the size parameters of the helical groove 112, different fixed dose specifications can be flexibly set. For example, increasing the axial length of the helical groove 112 can increase the movement range of the operation part 101 to adapt to larger dose requirements, and shortening the axial length of the helical groove 112 can reduce the movement range of the operation part 101 to adapt to small dose injection.

[0124] In the embodiment, the dose setting part 102 includes a dial 102-1 and a fixed card 102-2. The dial 102-1 and the fixed card 102-2 are independent structures and are fixedly connected in a mechanical manner. The dial 102-1 is provided with one of the helical protrusion 111 and the helical groove 112. The fixed card 102-2 is axially limitedly connected with the main shell part 100 and is circumferentially movable.

[0125] As set above, the dial 102-1 and the fixed card 102-2 are independent structures from each other, and the dial 102-1 and the fixed card 102-2 can be formed separately, thus simplifying the forming process and improving the forming efficiency. Meanwhile, only different dials 102-1 need to be replaced to realize different fixed dose specifications, thus adapting to the injection requirements of different doses, and the fixed card 102-2 can still be reused, thus improving the utilization rate of the fixed card 102-2 and reducing the cost.

[0126] Please refer to Figure 12 , Figures 15-17 , Figure 15 As Figure 12 the structure diagram of the dial in FIG. 1; Figure 16 As Figure 12 the structure diagram of the fixed card in FIG. 1; Figure 17 As Figure 12 the partial cross-sectional view of FIG. 1.

[0127] In the embodiment of the present application, the dial 102-1 is a cylindrical structure, the inside of the dial 102-2 is hollow, and the two axial ends are open ends. The fixed card 102-2 is partially fixed and inserted into the inside of the dial 102-2. One of the helical protrusions 111 and the helical grooves 112 is arranged on the outer wall of the dial 102-1, and the fixed card 102-2 is exposed at one end of the dial 102-2 for connection with the main shell part 100.

[0128] One of the outer peripheral wall of the fixed card 102-2 and the inner peripheral wall of the dial 102-1 is provided with a fixed protrusion 102-A, and the other is provided with a fixed hole 102-B. In the installed state, the fixed protrusion 102-A is clamped in the inside of the fixed hole 102-B, so as to realize the fixed connection of the dial 102-1 and the fixed card 102-2.

[0129] One of the outer peripheral wall of the fixed card 102-2 and the inner peripheral wall of the dial 102-1 has at least one limiting protruding rib 102-C arranged in the axial direction, and the other has at least one limiting groove 102-D arranged in the axial direction. In the installed state, the limiting protruding rib 102-C is inserted into the inside of the corresponding limiting groove 102-D.

[0130] As set above, the dial 102-1 and the fixed card 102-2 of the embodiment of the present application are formed in a rigid fit through the embedding design of the limiting protruding rib 102-C and the limiting groove 102-D, so that the dial 102-1 and the fixed card 102-2 are reliably constrained in the circumferential direction, and the dial 102-1 and the fixed card 102-2 can reliably rotate synchronously, thus improving the power transmission reliability and ensuring that the injection pen can still work stably in long-term use, and significantly optimizing the performance of the injection pen.

[0131] Please refer to Figure 18 , Figure 18 AsFigure 1 Partial cross-sectional view of the main housing portion and the dose setting portion in the assembled state in the injection pen.

[0132] As mentioned above, the dose setting portion 102 and the main housing portion 100 are axially limitedly connected and circumferentially movable. In the embodiment of the present application, the interior of the main housing portion 100 has an annular clamping groove 113, and the peripheral wall of the dose setting portion 102 is provided with a protruding portion 114 which can be inserted into the interior of the annular clamping groove 113. The axially one end of the protruding portion 114 forms an abutting wall 115 which is in contact with the first end wall 116 surrounding the annular clamping groove 113. The end of the dose setting portion 102 is provided with a plurality of circumferentially distributed protruding portions 117 which are in contact with the second end wall 118 surrounding the annular clamping groove 113. The axially limited connection of the dose setting portion 102 and the main housing portion 100 is realized by the abovementioned structure. The protruding portion 114 can rotate in the interior of the annular clamping groove 113, ensuring the circumferential movability of the dose setting portion 102 and the main housing portion 100, and ensuring the normal performance of the dose setting and injection actions.

[0133] As mentioned above, the protruding portion 114 and the annular clamping groove 113 are clamped and matched, realizing the reliable axial limitation of the dose setting portion 102 and the main housing portion 100. The protruding portions 117 can reduce the contact area between the dose setting portion 102 and the main housing portion 100, reduce the friction between the dose setting portion 102 and the main housing portion 100, and improve the rotating smoothness of the dose setting portion 102.

[0134] Please refer to Figures 19-21 , Figure 19 for Figure 1 Another partial cross-sectional view of the main housing portion in the injection pen; Figure 20 for Figure 19 Partial cross-sectional view of the main housing portion in the injection pen; Figure 21 for Figure 17 Structure schematic view of the fixing ring portion in the injection pen.

[0135] In the embodiment, the inner wall of the barrel part 100-11 is provided with a fixing groove 119 extending in the axial direction, and the end plate part 100-12 is located in the axial extension range of the fixing groove 119; the main shell part 100 further comprises a fixing ring part 100-3, the outer shell part 100-1 and the fixing ring part 100-3 are independent structures, one of the end walls of the fixing ring part 100-3 forms a first limiting wall 120, and the end part of the fixing ring part 100-3 is provided with a plurality of connecting arms 100-31 distributed in the circumferential direction, and the connecting arm 100-31 has a second limiting wall 121 facing the first limiting wall 120; the connecting arm 100-31 can pass from the inside of the fixing groove 119, and when the connecting arm 100-31 is installed in place, the end plate part 100-12 is clamped in the axial direction between the first limiting wall 120 and the second limiting wall 121, so as to realize the fixed connection of the outer shell part 100-1 and the fixing ring part 100-3.

[0136] The inner part of the fixing ring part 100-3 has a stepped wall part 100-32 facing the end plate part 100-12, and in the connected state, the stepped wall part 100-32 and the opposite wall part between the end plate part 100-12 form the aforementioned annular clamping groove 113, and the stepped wall part 100-32 forms the aforementioned first end wall 116, and the side wall of the end plate part 100-12 facing the stepped wall part 100-32 forms the aforementioned second end wall 118.

[0137] As arranged above, in the embodiment, the outer shell part 100-1 and the fixing ring part 100-3 are independent structures and are fixedly connected in a mechanical manner, and the outer shell part 100-1 and the fixing ring part 100-3 can be separately formed, and the structures of the outer shell part 100-1 and the fixing ring part 100-3 are both simpler, which is beneficial to simplify the forming process and improve the forming efficiency. The outer shell part 100-1 and the fixing ring part 100-3 are fixedly connected in a clamping manner, which is beneficial to simplify the assembly steps of the outer shell part 100-1 and the fixing ring part 100-3 and improve the assembly efficiency of the outer shell part 100-1 and the fixing ring part 100-3 while ensuring the reliable connection of the outer shell part 100-1 and the fixing ring part 100-3.

[0138] In the embodiment, the fixing groove 119 and the fixing groove part 100-A are the same recess structure provided on the inner wall of the outer shell part 100-1, which simultaneously realizes the fixed connection of the fixing ring part 100-3 and the outer shell part 100-1, and the bottle rack cover part 100-2 and the outer shell part 100-1. In some other embodiments of the application, the fixing groove 119 and the fixing groove part 100-A can be independent recess structures.

[0139] Please refer to Figures 22-23 , Figure 22 to Figure 1 the split figure of the tail cover part and the dose setting part in the injection pen;Figure 23 For Figure 1 Structure diagram of tail cover part and dose setting part when operation part in injection pen moves to limit position towards distal end of injection pen.

[0140] In the embodiment of the present application, one of the operation part 101 and the dose setting part 102 is provided with a blocking part 122, and the other is provided with a blocking groove 123. When the blocking part 122 is sunk into the blocking groove 123 to make the operation part 101 and the dose setting part 102 relatively fixed, the operation part 101 moves to the limit position towards the distal end of the injection pen.

[0141] As above, in the injection stage, when the blocking part 122 is sunk into the blocking groove 123 to make the operation part 101 and the dose setting part 102 relatively fixed, the operation part 101 cannot continue to move towards the distal end of the injection pen, indicating that the set dose of liquid medicine has been injected. It can be seen that the cooperation design of the blocking part 122 and the blocking groove 123 limits the end point of each injection, and this mechanical limiting method can realize the consistency of each injection dose. Moreover, when the blocking part 122 is sunk into the blocking groove 123 to make the operation part 101 and the dose setting part 102 relatively fixed, the operator will feel obvious resistance when continuing to push the operation part 101. The operator can clearly perceive that the operation part 101 has reached the injection end point, and the user experience is better.

[0142] In addition, the blocking part 122 and the blocking groove 123 limit the first limit position of the operation part 101 moving towards the distal end of the injection pen by mechanical limiting method, and the proximal end wall of the helical convex strip 111 and the proximal end wall of the helical groove 112 limit the second limit position of the operation part 101 moving towards the proximal end of the injection pen by mechanical limiting method. The first limit position and the second limit position jointly determine the axial movement range of the operation part 101. When performing dose setting each time, the operation part 101 moves from the first limit position to the second limit position, ensuring the consistency of each dose setting. When performing injection each time, the operation part 101 moves from the second limit position to the first limit position, ensuring the consistency of each injection dose, meeting the fixed dose injection requirement.

[0143] Please refer to Figure 24 , Figure 24 For Figure 1 Local sectional view of the rotating wheel, the driving rod part and the dose setting part in the injection pen in the assembled state.

[0144] In the embodiment, the injection pen further comprises a rotating wheel 124, the rotating wheel 124 is sleeved with the driving rod part 103 and is connected in a circumferential limiting manner and is movable in an axial direction, the rotating wheel 124 is threadedly connected with the dose setting part 102, and the driving rod part 103 is provided with a stop part 103-A configured to abut against the rotating wheel 124 to limit the limit position of the rotating wheel 124 moving towards the proximal end of the injection pen.

[0145] As arranged above, in the state that the operation part 101 moves towards the proximal end of the injection pen (dose setting stage), the driving rod part 103 is relatively stationary, and the dose setting part 102 rotates in a circumferential direction, thus the rotating wheel 124 can move towards the proximal end of the injection pen by a preset distance under the action of the thread of the dose setting part 102 and the circumferential limiting action of the driving rod part 103; in the state that the operation part 101 moves towards the distal end of the injection pen (injection stage), the driving rod part 103 rotates synchronously with the dose setting part 102, and the position of the rotating wheel 124 remains unchanged. Thus, the rotating wheel 124 can continue to move towards the proximal end of the injection pen by a preset distance on the basis of the last time each time the dose setting is performed; it can be seen that the rotating wheel 124 can gradually move towards the proximal end of the injection pen in the process of multiple dose settings through the thread cooperation with the dose setting part 102 and the circumferential limiting of the driving rod part 103, so as to accurately accumulate and record the total injection dose set; when the rotating wheel 124 abuts against the stop part 103-A, the rotating wheel 124 moves to the limit position towards the proximal end of the injection pen, at this time, the injection pen cannot set the dose any more, and thus cannot inject any more, prompting the user that the injection pen has completed the injection of the total effective dose, so as to enable the user to accurately master the medication situation.

[0146] By Figure 24 It can be seen that, in the embodiment, the stop part 103-A comprises a clamping hook arranged on the driving rod part 103, the clamping hook is provided with a stop wall facing the rotating wheel 124, and the stop wall is used for abutting against the rotating wheel 124 to limit the limit position of the rotating wheel 124 moving towards the proximal end of the injection pen.

[0147] Please refer to Figure 25 , Figure 25 To Figure 1 The structure schematic diagram of the rotating wheel and the driving rod part in the injection pen in an assembled state.

[0148] In the embodiment, the outer circumferential wall of the driving rod part 103 comprises a first plane part, the inner circumferential wall of the rotating wheel comprises a second plane part, in the mounted state, the rotating wheel 124 is sleeved with the driving rod part 103, the first plane part and the second plane part abut against each other, the first plane part and the second plane part form a circumferential limiting part, so as to ensure the circumferential limiting of the rotating wheel 124 and the driving rod part 103 is reliable, simplify the machining process of the rotating wheel 124 and the driving rod part 103, and improve the machining efficiency.

[0149] The circumferential limit of the rotating wheel 124 and the driving rod part 103 can be achieved in different ways. For example, the outer circumferential wall of the driving rod part 103 has protrusions extending along the axial direction, the inner circumferential wall of the rotating wheel 124 has grooves extending along the axial direction, the protrusions and the grooves are correspondingly inserted and fitted to achieve the circumferential limit of the rotating wheel 124 and the driving rod part 103, and the rotating wheel 124 is movable along the axial direction.

[0150] Please continue to refer to Figure 24 In the embodiment of the present application, the inner wall of the dose setting part 102 has a stepped portion 102-E, and when the rotating wheel 124 is in the initial position, the rotating wheel 124 abuts against the stepped portion 102-E.

[0151] The initial position mentioned here is the position of the injection pen when it has not been set any dose, and the stepped portion 102-E provides an accurate starting position for the rotating wheel 124, so that the axial movement stroke of the rotating wheel 124 is accurately limited between the stepped portion 102-E and the stop portion 103-A, ensuring the controllability and accuracy of the rotating wheel 124 during the dose accumulation process.

[0152] Please refer to Figures 26-28 , Figure 26 For Figure 3 is an enlarged view of the A area in FIG. 10; Figure 27 is Figure 1 is a partial enlarged view of the bottle holder part in the injection pen in the pre-assembly position; Figure 28 is Figure 1 is a partial enlarged view of the bottle holder part in the injection pen in the working position.

[0153] In the embodiment of the present application, the injection pen further comprises a bottle holder part 125, the main housing part 100 and the bottle holder part 125 are threadedly connected, and the injection pen further comprises a medicine bottle 001, the medicine bottle 001 is installed on the bottle holder part 125, the inside of the medicine bottle 001 has a sealing plug 002, and the sealing plug 002 is Figure 26 As can be seen, the inside of the medicine bottle 001 forms a containing cavity for containing the medicine liquid in the part area close to the distal end of the medicine bottle 001, and the screw rod part 106 extends into the inside of the medicine bottle 001, the bottle holder part 125 has a pre-assembly position and a working position, and can move from the pre-assembly position to the working position, wherein:

[0154] In the pre-assembly position, the screw rod part 106 and the sealing plug 002 have a spacing, and the sealing plug 002 is in the first position; in the working position, the screw rod part 106 and the sealing plug 002 abut, and the sealing plug 002 is in the second position, which is closer to the distal end of the medicine bottle 001 than the first position.

[0155] The related art injection pen replaces emptying with one injection when the fixed injection dose is large, causing drug waste. In the injection pen of the present application, the bottle holder part 125 has a pre-assembly position and a working position. Before use, the bottle holder part 125 is in the pre-assembly position, and there is a gap between the screw rod part 106 and the sealing plug 002, which can avoid the problem of drug overflow caused by the early contact between the screw rod part 106 and the sealing plug 002. When in use, the needle is installed at the distal end of the medicine bottle 001, and the user can rotate the bottle holder part 125 to switch the bottle holder part 125 from the pre-assembly position to the working position. During this process, the screw rod part 106 and the sealing plug 002 gradually approach each other and continue to move a distance after they abut each other. The completion of the emptying and exhaust before injection is confirmed by observing the overflow of the liquid medicine at the needle, which effectively avoids the problem of drug waste caused by one-time emptying operation during traditional large-dose injection, improves the reliability and user experience of the injection preparation stage, and ensures the accuracy and safety of the drug dose.

[0156] In the embodiment of the present application, one of the main housing part 100 and the bottle holder part 125 is provided with an elastic clamping part 126, and the other is provided with a first hole part 127 and a second hole part 128. In the pre-assembly position, the elastic clamping part 126 and the first hole part 127 are clamped and matched; in the working position, the elastic clamping part 126 and the second hole part 128 are clamped and matched.

[0157] As described above, the injection pen of the embodiment of the present application provides reliable mechanical locking for the bottle holder part 125 through the limiting structure composed of the elastic clamping part 126, the first hole part 127 and the second hole part 128 between the main housing part 100 and the bottle holder part 125. Specifically, through the clamping and matching of the elastic clamping part 126 and the first hole part 127, the bottle holder part 125 can be reliably in the pre-assembly position, effectively preventing the early contact between the screw rod part 106 and the sealing plug 002 caused by accidental relative rotation during transportation and storage, which can cause drug overflow and ensure the sealing and safety of the drug. When needed, the user rotates the bottle holder part 125, the elastic clamping part 126 can be detached from the first hole part 127 and finally clamped with the second hole part 128, which ensures that the bottle holder part 125 can be reliably in the working position, and the relative position of the screw rod part 106 and the sealing plug 002 is reliable, ensuring the accuracy and safety of the dose, and improving the dose reliability and user experience of the injection pen.

[0158] Please refer to Figure 29 , Figure 29 for Figure 1 the structure diagram of the connection between the main housing part and the bottle holder part in the injection pen.

[0159] In the embodiment of the present application, the injection pen is provided with an indication mark 129, through which the user can clearly know the rotating direction of the bottle support part 125, so as to facilitate the switching of the position of the bottle support part 125 and complete the injection preparation.

[0160] In the embodiment of the present application, the indication mark 129 adopts an arrow, and the end of the arrow points to the rotating direction of the bottle support part 125.

[0161] As shown in Figure 1 In the embodiment of the present application, the injection pen further comprises a shell cover part 130, which can be detachably sleeved on the outer periphery of the bottle support part 125 and plays a safety protection role.

[0162] As shown in Figure 26 In the embodiment of the present application, the injection pen further comprises a screw rod gasket 131, which is connected to the distal end of the screw rod part 106. The screw rod part 106 abuts against the sealing plug 002 through the screw rod gasket 131, so as to increase the contact area of the screw rod part 106 and the sealing plug 002, better transmit the pushing force to the sealing plug 002, and complete the injection action.

[0163] The above is only the preferred embodiment of the present application, and it should be pointed out that, for those skilled in the art, some improvements and refinements can be made without departing from the principle of the present application, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. An injection pen, characterized in that, include: Main housing section; The operating part is partially installed inside the main housing part in a circumferential direction and can move within a preset range in an axial direction; The dosage setting unit is threadedly connected to the operation unit, and the dosage setting unit is axially limited to the main housing unit and is circumferentially movable. The driving rod portion and the main housing portion are provided with a first one-way limiting structure, and the driving rod portion and the dose setting portion are provided with a second one-way limiting structure, such that when the operating portion moves toward the proximal end of the injection pen, the driving rod portion and the main housing portion are relatively stationary, and when the operating portion moves toward the distal end of the injection pen, the driving rod portion and the dose setting portion rotate synchronously. The screw portion passes through the interior of the drive rod portion. One of the main housing portion and the drive rod portion is threadedly connected to the screw portion. The other of the main housing portion and the drive rod portion is circumferentially limited and axially movable to the screw portion. The first one-way limiting structure includes a first one-way slot disposed in one of the drive rod portion and the main housing portion and distributed circumferentially, and a first elastic snap-fit ​​portion disposed in the other of the drive rod portion and the main housing portion, wherein the first elastic snap-fit ​​portion snaps into either of the first one-way slots. When the operating part moves toward the proximal end of the injection pen, the first elastic locking part and the peripheral wall surrounding the first one-way slot abut against each other to achieve circumferential limiting; when the operating part moves toward the distal end of the injection pen, the first elastic locking part slides along the peripheral wall surrounding the first one-way slot to engage with one of the first one-way slots at the front end. The second one-way limiting structure includes a second one-way slot disposed in one of the drive rod portion and the dose setting portion and distributed circumferentially, and a second elastic locking portion disposed in the other of the drive rod portion and the dose setting portion, wherein the second elastic locking portion is engaged in either of the second one-way slots; When the operating part moves toward the proximal end of the injection pen, the second elastic locking part slides along the peripheral wall surrounding the second one-way slot to engage with one of the second one-way slots at the front end; when the operating part moves toward the distal end of the injection pen, the second elastic locking part and the peripheral wall surrounding the second one-way slot abut against each other to achieve circumferential limiting.

2. The injection pen according to claim 1, characterized in that, The main housing includes an outer shell and a bottle holder cap. The outer shell and the bottle holder cap are independent structures and are mechanically fixed together. The bottle holder cap is provided with one of the first elastic snap-fit ​​part and the first one-way snap-fit ​​groove. The bottle holder cap and the screw part are threaded together, or the bottle holder cap and the screw part are circumferentially limited and axially movable.

3. The injection pen according to any one of claims 1-2, characterized in that, In the dosage setting unit and the operation unit, one is provided with a spiral protrusion and the other is provided with a spiral groove. The spiral protrusion is embedded inside the spiral groove. The proximal end of the spiral groove is a closed end. When the proximal end wall of the spiral protrusion and the proximal end wall of the spiral groove are in contact, the operation unit moves toward the proximal end of the injection pen to its limit position.

4. The injection pen according to claim 3, characterized in that, The dosage setting unit includes a dial and a fixing clip. The dial and the fixing clip are independent structures and are mechanically fixedly connected. The dial is provided with one of the helical protrusion and the helical groove. The fixing clip is axially limited to the main housing and is movable in the circumferential direction.

5. The injection pen according to any one of claims 1-2, characterized in that, At one end of the operating part and the dose setting part that are relatively close to each other along the axial direction, one is provided with a blocking part and the other is provided with a blocking groove. When the blocking part is inserted into the blocking groove, making the operating part and the dose setting part relatively fixed, the operating part moves toward the distal end of the injection pen to the limit position.

6. The injection pen according to any one of claims 1-2, characterized in that, The injection pen also includes a rotating wheel, which is fitted onto the drive rod and circumferentially limited, and is axially movable. The rotating wheel is threadedly connected to the dose setting part. The drive rod has a stop part, which is configured to abut against the rotating wheel to limit the extreme position of the rotating wheel's movement toward the proximal end of the injection pen.

7. The injection pen according to any one of claims 1-2, characterized in that, The injection pen also includes a vial support portion, the main housing portion and the vial support portion are threadedly connected, the injection pen also includes a medicine bottle, the medicine bottle is mounted on the vial support portion, the medicine bottle has a sealing plug inside, the screw portion extends into the medicine bottle, the vial support portion has a pre-assembly position and a working position, and can move from the pre-assembly position to the working position, wherein: In the pre-assembled position, there is a gap between the screw and the sealing plug, and the sealing plug is in a first position; in the working position, the screw and the sealing plug abut against each other, and the sealing plug is in a second position, which is closer to the far end of the vial than the first position.

8. The injection pen according to claim 7, characterized in that, In the main housing and the bottle support, one is provided with an elastic snap-fit ​​part, and the other is provided with a first hole and a second hole. In the pre-assembly position, the elastic snap-fit ​​part and the first hole are engaged; in the working position, the elastic snap-fit ​​part and the second hole are engaged.

Images