Automatic injection pen

Abstract

The utility model relates to the technical field of medical instruments and discloses an automatic injection pen which comprises an injection pen body, a limiting sleeve and a button. The limiting sleeve is connected to one end, in the first direction, of the injection pen body, the limiting sleeve is provided with a first limiting groove and a second limiting groove, the first limiting groove extends in the circumferential direction of the limiting sleeve, the second limiting groove extends in the first direction, the first limiting groove is communicated with the second limiting groove, and in the first direction, the second limiting groove is communicated with the limiting sleeve. The second limiting groove is at least partially located on the side, close to the injection pen body, of the first limiting groove. In the first direction, the button is connected to the end, away from the injection pen body, of the limiting sleeve, the button is provided with a clamping part, the clamping part is inserted into the first limiting groove, and when the automatic injection pen does not inject, under the limitation of the first limiting groove, the button cannot move towards the side where the injection pen body is located in the first direction; even if the button is touched accidentally, injection work cannot be triggered, and the automatic injection pen has the function of preventing mistaken touch.

Description

TECHNICAL FIELD

[0001] The utility model relates to medical instrument technical field, in particular to an automatic injection pen. BACKGROUND

[0002] Automatic injection pen is a kind of medical instrument for assisting drug injection, in relevant technologies, some automatic injection pens are used to inject insulin, growth hormone and other drugs with more accurate dosage requirements, thus, if automatic injection pen inadvertently bumps into injection button and other operating components during carrying and storage, it can cause drug to be accidentally injected, so that the originally set dosage of drug appears deviation, which can cause inaccurate dosage when normally taking drug subsequently, thus, automatic injection pen needs to have anti-mis-touch function to avoid the problem of injection dosage error in actual application. SUMMARY

[0003] The utility model discloses a kind of automatic injection pens with anti-mis-touch function.

[0004] To achieve the above purpose, the utility model provides an automatic injection pen, including injection pen main body, limit sleeve and button;

[0005] The axial direction of the injection pen main body is the first direction;

[0006] The axial direction of the limit sleeve is the same as the first direction, and the limit sleeve is connected to one end of the injection pen main body in the first direction. The limit sleeve is provided with a first limiting groove and a second limiting groove. The first limiting groove extends along the circumferential direction of the limit sleeve, and the second limiting groove extends along the first direction. The first limiting groove is in communication with the second limiting groove, and in the first direction, the second limiting groove is at least partially located on the side of the first limiting groove close to the injection pen main body.

[0007] In the first direction, the button is connected to one end of the limit sleeve away from the injection pen main body. The button has a clamping portion, and the clamping portion is inserted into the first limiting groove.

[0008] The button can rotate relative to the limit sleeve around the axis of the injection pen main body. The first limiting groove can allow the clamping portion to move along the extension direction of the first limiting groove, and the second limiting groove can allow the clamping portion to move along the first direction.

[0009] In a specific embodiment of the utility model, the injection pen main body includes a housing. The housing has an open end and a clamping groove. In the first direction, the open end is provided on the end face of one end of the housing, and the clamping groove is provided on the inner wall surface of the housing and extends along the first direction.

[0010] The limiting sleeve comprises a first sleeve body and a second sleeve body connected along the first direction, the first sleeve body is arranged outside the shell, and the second sleeve body is arranged in the shell through the opening, and the second sleeve body is rotationally connected with the shell;

[0011] The first limiting groove and the second limiting groove are arranged on the outer wall surface of the second sleeve body and penetrate into the second sleeve body, the button penetrates through the first sleeve body and is arranged in the second sleeve body, the clamping portion penetrates through the first limiting groove and is clamped in the clamping groove, and the clamping groove can allow the clamping portion to move along the first direction.

[0012] In a specific embodiment of the utility model, the inner wall surface of the shell is provided with a guide groove, the guide groove is arc-shaped, and the guide groove extends along the circumference of the shell.

[0013] The limiting sleeve further comprises a guide block, the guide block is connected to the outer wall surface of the second sleeve body, the guide block is arranged in the guide groove, and the guide groove can allow the guide block to move along the extension direction of the guide groove.

[0014] In a specific embodiment of the utility model, the injection pen body further comprises a first positioning protrusion, the first positioning protrusion is connected to the groove wall surface of the guide groove perpendicular to the first direction, the first positioning protrusion divides the guide groove into a first guide area and a second guide area, and the first guide area and the second guide area are arranged along the extension direction of the guide groove.

[0015] The guide block is arranged in the first guide area.

[0016] The limiting sleeve further comprises a second positioning protrusion, in the first direction, the second positioning protrusion is connected to one side of the guide block facing the side where the first positioning protrusion is located.

[0017] The first positioning protrusion is used for contacting the second positioning protrusion to resist the guide block from entering the second guide area from the first guide area, and under the action of an external force, rotating the limiting sleeve can make the guide block enter the second guide area from the first guide area, and when the guide block is located in the second guide area, in the first direction, the clamping portion is opposite to the second limiting groove.

[0018] In a specific embodiment of the utility model, the outer wall surface of the first sleeve body is provided with anti-skid lines.

[0019] In a specific embodiment of the utility model, the limiting sleeve further comprises an anti-rolling protrusion, and the anti-rolling protrusion is connected to the outer wall surface of the first sleeve body.

[0020] In a specific embodiment of the utility model, the button comprises a knob cap and a connecting rod, the knob cap is inserted into the first sleeve, in the first direction, the connecting rod is connected to one end of the knob cap on the side facing the shell, the connecting rod is inserted into the first sleeve and the second sleeve, and the clamping portion is located on one end of the connecting rod away from the knob cap.

[0021] In a specific embodiment of the utility model, the limiting sleeve further comprises an inner cylinder, a connecting plate and a locking assembly, the inner cylinder is arranged in the first sleeve, the outer wall surface of the inner cylinder is connected to the inner wall surface of the first sleeve through the connecting plate, and the locking assembly is connected to the inner cylinder;

[0022] The injection pen body further comprises a plunger assembly, the plunger assembly is arranged in the shell, in the first direction, one end of the plunger assembly penetrates the second sleeve and is inserted into the inner cylinder, and the plunger assembly is connected to the locking assembly, and the locking assembly is used for locking the plunger assembly;

[0023] The button further comprises an unlocking portion, and the unlocking portion is connected to the knob cap;

[0024] When the button moves along the first direction towards the side where the injection pen body is located under the action of an external force, the unlocking portion can unlock the locking of the plunger assembly by the locking assembly.

[0025] In a specific embodiment of the utility model, the inner cylinder is inserted into the knob cap, the inner cylinder is provided with an avoiding groove extending along the first direction, and one end of the avoiding groove close to the knob cap is an open end;

[0026] The button further comprises a stop block, the stop block is connected to the knob cap, and the stop block is in contact with the end face of one end of the inner cylinder close to the knob cap;

[0027] The limiting sleeve is rotated under the action of an external force, so that the stop block faces the avoiding groove in the first direction.

[0028] In a specific embodiment of the utility model, in the first direction, one side of the button away from the injection pen body is formed with a pressing groove.

[0029] Compared with the prior art, the utility model discloses an automatic injection pen, and has the beneficial effects that:

[0030] The automatic injection pen of the utility model embodiment, through pressing the button, the button moves along the first direction to the side where the injection pen body is located, so as to trigger the injection function, since the first limiting groove extends along the circumference of the limiting sleeve, and the clamping part of the button is inserted into the first limiting groove, therefore, when the automatic injection pen is not injecting, under the limitation of the first limiting groove, the button cannot move along the first direction to the side where the injection pen body is located, even if the button is accidentally touched, the injection work will not be triggered, the automatic injection pen has the anti-misoperation function, and can avoid the problem of injection dose error in actual application; when the automatic injection pen is injecting, since the second limiting groove extends along the first direction, the button can rotate relative to the limiting sleeve around the axis of the injection pen body, the first limiting groove can allow the clamping part to move along the extension direction of the first limiting groove, and the second limiting groove can allow the clamping part to move along the first direction, therefore, by rotating the button to the position opposite to the second limiting groove in the first direction, the button can be pressed to move along the first direction to the side where the injection pen body is located, so as to trigger the injection function, the automatic injection pen with the anti-misoperation function in the form of rotation has simple structure and convenient and intuitive operation. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is the front view of the automatic injection pen of the utility model embodiment;

[0032] Figure 2 It is the front view of the automatic injection pen of the utility model embodiment Figure 1 It is the enlarged schematic view of A in the utility model embodiment;

[0033] Figure 3 It is the exploded schematic view of the automatic injection pen of the utility model embodiment;

[0034] Figure 4 It is the perspective view of the limiting sleeve and the button of the utility model embodiment;

[0035] Figure 5 It is the perspective view of the button of the utility model embodiment;

[0036] Figure 6 It is the perspective view of the limiting sleeve and the button of the utility model embodiment;

[0037] X, first direction; 1, injection pen main body; 11, shell; 1101, open end; 1102, clamping groove; 1103, guide groove; 1103A, first guide area; 1103B, second guide area; 12, first positioning protrusion; 13, plunger assembly; 2, limiting sleeve; 201, first limiting groove; 202, second limiting groove; 21, first sleeve body; 2101, anti-skid pattern; 22, second sleeve body; 23, guide block; 24, second positioning protrusion; 25, anti-rolling protrusion; 26, inner cylinder body; 2601, avoiding groove; 27, connecting plate; 28, locking assembly; 3, button; 301, clamping part; 302, pressing groove; 31, knob cap; 32, connecting rod; 33, unlocking part; 34, stop block. DETAILED DESCRIPTION

[0038] The specific embodiments of the utility model will be further described in detail below in combination with the drawings and examples. The following examples are used to illustrate the utility model, but not to limit the scope of the utility model.

[0039] As Figures 1 to 6 shown, the utility model discloses an automatic injection pen, including injection pen main body 1, limiting sleeve 2 and button 3;The axial direction of injection pen main body 1 is first direction X;The axial direction of limiting sleeve 2 is same with first direction X, and limiting sleeve 2 is connected to one end of injection pen main body 1 in first direction X, and limiting sleeve 2 is equipped with first limiting groove 201 and second limiting groove 202, and first limiting groove 201 extends along the circumference of limiting sleeve 2, and second limiting groove 202 extends along first direction X, and first limiting groove 201 is communicated with second limiting groove 202, and in first direction X, second limiting groove 202 is at least partially located on the side of first limiting groove 201 close to injection pen main body 1;In first direction X, button 3 is connected to the end of limiting sleeve 2 away from injection pen main body 1, and button 3 has clamping part 301, and clamping part 301 is inserted into first limiting groove 201;Wherein, button 3 can rotate relative to limiting sleeve 2 around the axis of injection pen main body 1, first limiting groove 201 can move clamping part 301 along the extension direction of first limiting groove 201, and second limiting groove 202 can move clamping part 301 along first direction X.

[0040] The automatic injection pen of the embodiment is triggered to inject by pressing the button 3 to move the button 3 along the first direction X to the side where the injection pen body 1 is located. Since the first limiting groove 201 extends along the circumference of the limiting sleeve 2 and the clamping portion 301 of the button 3 is inserted into the first limiting groove 201, the button 3 cannot move along the first direction X to the side where the injection pen body 1 is located under the limitation of the first limiting groove 201 when the automatic injection pen is not injecting. Even if the button 3 is accidentally touched, the injection work will not be triggered. The automatic injection pen has the anti-misoperation function, which can avoid the problem of incorrect injection dose in actual application. When the automatic injection pen is injecting, the button 3 can rotate relative to the limiting sleeve 2 around the axis of the injection pen body 1 since the second limiting groove 202 extends along the first direction X. The first limiting groove 201 can allow the clamping portion 301 to move along the extension direction of the first limiting groove 201, and the second limiting groove 202 can allow the clamping portion 301 to move along the first direction X. Therefore, the button 3 can be pressed to move along the first direction X to the side where the injection pen body 1 is located by rotating the button 3 to the position opposite to the second limiting groove 202 in the first direction X to trigger the injection function. The automatic injection pen with the anti-misoperation function released by rotation has a simple structure and is convenient and intuitive to operate.

[0041] As shown in Figure 3 , Figure 4 and Figure 6 , the injection pen body 1 includes a shell 11 having an opening 1101 and a clamping groove 1102. The opening 1101 is arranged on the end face of one end of the shell 11 in the first direction X, and the clamping groove 1102 is arranged on the inner wall face of the shell 11 and extends along the first direction X. The limiting sleeve 2 includes a first sleeve body 21 and a second sleeve body 22 connected along the first direction X. The first sleeve body 21 is arranged outside the shell 11, and the second sleeve body 22 is inserted into the shell 11 through the opening 1101 and is rotationally connected with the shell 11. The first limiting groove 201 and the second limiting groove 202 are arranged on the outer wall face of the second sleeve body 22 and penetrate into the second sleeve body 22. The button 3 is inserted into the second sleeve body 22 through the first sleeve body 21. The clamping portion 301 is inserted into the first limiting groove 201 and clamped in the clamping groove 1102. The clamping groove 1102 can allow the clamping portion 301 to move along the first direction X. The automatic injection pen with such a structure can prevent the button 3 from rotating with the rotation of the limiting sleeve 2 under the limitation of the clamping groove 1102, effectively ensuring the normal unlocking of the anti-misoperation function during injection. The clamping groove 1102 extends along the first direction X by a predetermined distance, which can ensure that the button 3 can move along the first direction X to the side where the injection pen body 1 is located, thereby ensuring the normal injection work. The limiting sleeve 2 is rotationally connected with the shell 11 through the second sleeve body 22, and the first sleeve body 21 is exposed outside the shell 11. Therefore, the user can rotate the first sleeve body 21 to rotate the limiting sleeve 2, which is convenient to operate.

[0042] Preferably, the outer diameter of the first sleeve body 21 is larger than the outer diameter of the second sleeve body 22, and the first sleeve body 21 is in contact with the end face of the shell 11 provided with the opening 1101, so that when the limiting sleeve 2 is assembled with the shell 11, the first sleeve body 21 plays a positioning role, and when the first sleeve body 21 is in contact with the shell 11, it indicates that the limiting sleeve 2 is installed in place, facilitating the assembly of the limiting sleeve 2.

[0043] Further, the inner wall surface of the shell 11 is provided with a guide groove 1103, the guide groove 1103 is arc-shaped, and the guide groove 1103 extends along the circumference of the shell 11; the limiting sleeve 2 further comprises a guide block 23, the guide block 23 is connected to the outer wall surface of the second sleeve body 22, the guide block 23 is inserted into the guide groove 1103, and the guide groove 1103 can move the guide block 23 along the extension direction of the guide groove 1103, as shown in Figure 2 , the guide groove 1103 penetrates through the shell 11, which is simple in structure and convenient to produce; specifically, the cooperation of the guide block 23 and the guide groove 1103 can ensure the accurate rotation direction of the limiting sleeve 2, avoid deviation and shaking, and ensure the smooth operation of the anti-misoperation release; in addition, it can also make the limiting sleeve 2 and the shell 11 connect stably.

[0044] Further, as shown in Figure 2As shown, the injection pen body 1 further comprises a first positioning protrusion 12 connected to the groove wall surface of the guide groove 1103 perpendicular to the first direction X, the first positioning protrusion 12 separates the guide groove 1103 into a first guide area 1103A and a second guide area 1103B, the first guide area 1103A and the second guide area 1103B are arranged along the extension direction of the guide groove 1103; the guide block 23 is inserted into the first guide area 1103A; the limiting sleeve 2 further comprises a second positioning protrusion 24, in the first direction X, the second positioning protrusion 24 is connected to one side of the guide block 23 facing the side where the first positioning protrusion 12 is located; wherein the first positioning protrusion 12 is used to contact the second positioning protrusion 24 to resist the guide block 23 from entering the second guide area 1103B from the first guide area 1103A, and under the action of external force, rotating the limiting sleeve 2 can make the guide block 23 enter the second guide area 1103B from the first guide area 1103A, when the guide block 23 is located in the second guide area 1103B, in the first direction X, the clamping part 301 is opposite to the second limiting groove 202, specifically, because the first positioning protrusion 12 will resist the second positioning protrusion 24 during the process of the guide block 23 entering the second guide area 1103B from the first guide area 1103A, therefore, the user can clearly perceive the resistance during the process of rotating the limiting sleeve 2, therefore, the user only needs to increase the force to make the second positioning protrusion 24 pass the first positioning protrusion 12 to make the guide block 23 enter the second guide area 1103B from the first guide area 1103A, thereby playing a prompting role to prompt the user that the limiting sleeve 2 has been rotated in place, convenient to use; in addition, because the first positioning protrusion 12 will resist the second positioning protrusion 24, therefore, if there is no certain force to make the first positioning protrusion 12 pass the second positioning protrusion 24, the anti-misoperation will not be released, therefore, it can avoid that the automatic injection pen releases the anti-misoperation in the case of non-human operation injection, and the anti-misoperation function of the automatic injection pen is reliable; for example, Figure 2 As shown, the first positioning protrusion 12 and the second positioning protrusion 24 are both protrusions with arc surfaces, the surfaces used for contacting are both arc surfaces, such structure can make the first positioning protrusion 12 resist the movement of the second positioning protrusion 24, and at the same time, under a certain force, the second positioning protrusion 24 can pass the first positioning protrusion 12.

[0045] Further, as shown in the figure, Figure 3 The outer wall surface of the first sleeve body 21 is provided with anti-skid lines 2101, thereby making the limiting sleeve 2 have certain anti-skid function, avoiding the phenomenon of slipping during the rotation of the limiting sleeve 2, so as to facilitate the injection operation.

[0046] In the present application, as shown in the figure, Figure 1 The automatic injection pen as a whole is cylindrical, thereby in the present embodiment, as shown in the figure, Figure 4As shown, the limiting sleeve 2 further comprises an anti-rolling protrusion 25 connected to the outer wall surface of the first sleeve body 21, based on which, the automatic injection pen can avoid rolling when placed horizontally, can be stably placed, and can reduce the possibility of falling from a height.

[0047] In the embodiment, as shown in Figure 5 As shown, the button 3 comprises a knob cap 31 and a connecting rod 32, the knob cap 31 is inserted into the first sleeve body 21, in the first direction X, the connecting rod 32 is connected to one end of the knob cap 31 on the side facing the shell 11, the connecting rod 32 is inserted into the first sleeve body 21 and the second sleeve body 22, and the clamping portion 301 is located on one end of the connecting rod 32 away from the knob cap 31. The button 3 with such a structure is simple in structure, and by arranging the clamping portion 301 on the connecting rod 32, the material of the button 3 can be reduced, and the production cost can be saved.

[0048] As shown in Figure 3 , Figure 5 and Figure 6 As shown, the limiting sleeve 2 further comprises an inner cylinder 26, a connecting plate 27 and a locking assembly 28, the inner cylinder 26 is arranged in the first sleeve body 21, the outer wall surface of the inner cylinder 26 is connected to the inner wall surface of the first sleeve body 21 through the connecting plate 27, and the locking assembly 28 is connected in the inner cylinder 26; the injection pen body 1 further comprises a plunger assembly 13, the plunger assembly 13 is arranged in the shell 11, in the first direction X, one end of the plunger assembly 13 penetrates the second sleeve body 22 and is inserted into the inner cylinder 26, and is connected with the locking assembly 28, the locking assembly 28 is used for locking the plunger assembly 13; the button 3 further comprises an unlocking portion 33, the unlocking portion 33 is connected in the knob cap 31; when the button 3 moves along the first direction X towards the side where the injection pen body 1 is located under the action of an external force, the unlocking portion 33 can unlock the locking of the plunger assembly 13 by the locking assembly 28; specifically, the locking assembly 28 is arranged in the first sleeve body 21, the locking assembly 28 is relatively close to the button 3, thus, the button 3 can complete the unlocking work with a relatively small stroke in the first direction X, and is convenient to use.

[0049] It should be noted that the plunger assembly 13 is a basic component of the automatic injection pen in the prior art, and the automatic injection pen further comprises a needle cylinder and the like, the plunger assembly 13 comprises a plunger and a driving member, the needle cylinder is used for storing an injection, the plunger at least partially extends into the needle cylinder, and the driving member is used for driving the plunger to push the injection in the needle cylinder to output, in the embodiment, the driving member is a spring, as shown in Figure 3 As can be seen, the driving member is a spring, as shown in Figure 6It can be seen that the locking assembly 28 locks one end of the plunger, and the locking assembly 28 is a plurality of clamping claws. In actual application, the unlocking portion 33 is used to press the clamping claws to move the clamping claws away from the center of the plunger to release the plunger. At this time, under the action of the driving member, the plunger moves away from the button 3 in the first direction X, so as to extrude the injection in the needle cylinder. This part of the structure of the automatic injection pen is prior art, and the present application does not make too much description.

[0050] Further, as shown in Figures 4 to 6 The inner cylinder body 26 is inserted into the knob cap 31, and the inner cylinder body 26 is provided with an avoiding groove 2601 extending in the first direction X. The end of the avoiding groove 2601 close to the knob cap 31 is an open end. The button 3 further comprises a stop block 34 connected to the knob cap 31, and the stop block 34 is in contact with the end face of the end of the inner cylinder body 26 close to the knob cap 31. Rotating the limiting sleeve 2 under the action of an external force can make the stop block 34 face the avoiding groove 2601 in the first direction X. At this time, the clamping portion 301 faces the second limiting groove 202 in the first direction X. Specifically, since the stop block 34 is in contact with the inner cylinder body 26, the inner cylinder body 26 can also function to limit the movement of the button 3 in the first direction X towards the side where the injection pen body is located. In cooperation with the clamping portion 301, multiple safeguards are provided to avoid accidental injection and reduce the possibility of failure of the anti-misoperation function.

[0051] In the embodiment, as shown in Figure 4 In the first direction X, the side of the button 3 away from the injection pen body 1 is formed with a pressing groove 302. The provision of the pressing groove 302 can provide a clear and suitable placement position for the finger. The user does not need to deliberately search for and align the button 3. Only by naturally placing the finger in the pressing groove 302, the pressing operation can be quickly positioned and prepared. When pressing, the finger is not easy to slip, deviate, etc., and the operation is convenient.

[0052] The above is only the preferred embodiment of the present application. It should be pointed out that for ordinary skilled persons in the technical field, without departing from the technical principles of the present application, a number of improvements and substitutions can be made, and these improvements and substitutions should be regarded as the protection scope of the present application.

Claims

1. An auto-injector, characterized in that, The injection pen body (1), the limiting sleeve (2) and the button (3) are included. The axial direction of the injection pen body (1) is the first direction (X); The axial direction of the limiting sleeve (2) is the same as the first direction (X), the limiting sleeve (2) is connected to one end of the injection pen body (1) in the first direction (X), the limiting sleeve (2) is provided with a first limiting groove (201) and a second limiting groove (202), the first limiting groove (201) extends along the circumference of the limiting sleeve (2), the second limiting groove (202) extends along the first direction (X), the first limiting groove (201) and the second limiting groove (202) are communicated, and in the first direction (X), the second limiting groove (202) is at least partially located on the side of the first limiting groove (201) close to the injection pen body (1); In the first direction (X), the button (3) is connected to one end of the limiting sleeve (2) away from the injection pen body (1), the button (3) has a clamping part (301), and the clamping part (301) is inserted into the first limiting groove (201); Wherein, the button (3) can rotate relative to the limiting sleeve (2) around the axis of the injection pen body (1), the first limiting groove (201) can move the clamping part (301) along the extension direction of the first limiting groove (201), and the second limiting groove (202) can move the clamping part (301) along the first direction (X).

2. The auto-injector pen of claim 1, wherein, The injection pen body (1) includes a shell (11), the shell (11) has an opening (1101) and a clamping groove (1102), in the first direction (X), the opening (1101) is arranged on the end face of one end of the shell (11), the clamping groove (1102) is arranged on the inner wall surface of the shell (11), and the clamping groove (1102) extends along the first direction (X); The limiting sleeve (2) includes a first sleeve body (21) and a second sleeve body (22) connected along the first direction (X), the first sleeve body (21) is arranged outside the shell (11), the second sleeve body (22) is inserted into the shell (11) through the opening (1101), and the second sleeve body (22) is rotationally connected with the shell (11); Wherein, the first limiting groove (201) and the second limiting groove (202) are arranged on the outer wall surface of the second sleeve body (22) and penetrate into the second sleeve body (22), the button (3) penetrates the first sleeve body (21) and is inserted into the second sleeve body (22), the clamping part (301) penetrates the first limiting groove (201) and is clamped in the clamping groove (1102), and the clamping groove (1102) can move the clamping part (301) along the first direction (X).

3. The auto-injector pen of claim 2, wherein, The inner wall surface of the shell (11) is provided with a guide groove (1103), the guide groove (1103) is arc-shaped, and the guide groove (1103) extends along the circumference of the shell (11); The limiting sleeve (2) further comprises a guide block (23) connected to the outer wall surface of the second sleeve body (22), the guide block (23) is inserted into the guide groove (1103), and the guide groove (1103) can move the guide block (23) along the extension direction of the guide groove (1103).

4. The auto-injector pen of claim 3, wherein, The injection pen body (1) further comprises a first positioning protrusion (12) connected to the groove wall surface of the guide groove (1103) perpendicular to the first direction (X), the first positioning protrusion (12) separates the guide groove (1103) into a first guide area (1103A) and a second guide area (1103B), and the first guide area (1103A) and the second guide area (1103B) are arranged along the extension direction of the guide groove (1103); The guide block (23) is inserted into the first guide area (1103A); The limiting sleeve (2) further comprises a second positioning protrusion (24), in the first direction (X), the second positioning protrusion (24) is connected to one side of the guide block (23) facing the side where the first positioning protrusion (12) is located; The first positioning protrusion (12) is used to contact the second positioning protrusion (24) to resist the guide block (23) from entering the second guide area (1103B) from the first guide area (1103A), and under the action of external force, rotating the limiting sleeve (2) can make the guide block (23) enter the second guide area (1103B) from the first guide area (1103A), when the guide block (23) is located in the second guide area (1103B), in the first direction (X), the clamping part (301) is opposite to the second limiting groove (202).

5. The auto-injector pen of claim 2, wherein, The outer wall surface of the first sleeve body (21) is provided with anti-skid lines (2101).

6. The auto-injector pen of claim 2, wherein, The limiting sleeve (2) further comprises an anti-rolling protrusion (25) connected to the outer wall surface of the first sleeve body (21).

7. The auto-injector pen of claim 2, wherein, The button (3) comprises a knob cap (31) and a connecting rod (32), the knob cap (31) is inserted into the first sleeve body (21), in the first direction (X), the connecting rod (32) is connected to one end of the knob cap (31) facing the side where the shell (11) is located, the connecting rod (32) is inserted into the first sleeve body (21) and the second sleeve body (22), and the clamping part (301) is located on one end of the connecting rod (32) away from the knob cap (31).

8. The auto-injector pen of claim 7, wherein, The limiting sleeve (2) further comprises an inner cylinder (26), a connecting plate (27) and a locking assembly (28), the inner cylinder (26) is arranged in the first sleeve body (21), the outer wall surface of the inner cylinder (26) is connected to the inner wall surface of the first sleeve body (21) through the connecting plate (27), and the locking assembly (28) is connected to the inner cylinder (26); The injection pen body (1) further comprises a plunger assembly (13) arranged in the shell (11), one end of the plunger assembly (13) is arranged through the second sleeve (22) and inserted into the inner cylinder (26) in the first direction (X), and is connected with the locking assembly (28) for locking the plunger assembly (13); The button (3) further comprises an unlocking part (33) connected in the knob cap (31); When the button (3) is moved along the first direction (X) towards the side where the injection pen body (1) is located under the action of external force, the unlocking part (33) can unlock the locking of the plunger assembly (13) by the locking assembly (28).

9. The auto-injector pen of claim 8, wherein, The inner cylinder (26) is inserted into the knob cap (31), and the inner cylinder (26) is provided with an avoiding groove (2601) extending along the first direction (X), and the end of the avoiding groove (2601) close to the knob cap (31) is an open end; The button (3) further comprises a stop block (34) connected in the knob cap (31), and the stop block (34) is in contact with the end face of the inner cylinder (26) close to the knob cap (31); Rotating the limiting sleeve (2) under the action of external force can make the stop block (34) face the avoiding groove (2601) in the first direction (X).

10. The auto-injector of claim 1, wherein, In the first direction (X), the side of the button (3) away from the injection pen body (1) is formed with a pressing groove (302).

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