Auto-injectors

Abstract

The present application relates to an automatic injector, comprising a syringe and a pushing mechanism, the syringe comprises a syringe body and a needle part arranged at one end of the syringe body in the axial direction, and a first stop part is arranged on the syringe body. The pushing mechanism comprises a pushing piece and a first elastic piece, one end of the pushing piece extends into the syringe, the first elastic piece is used for pushing the pushing piece to move towards the needle part, and a second stop part is arranged on the pushing piece for cooperating with the first stop part. In use, the initial distance between the first stop part and the second stop part is determined according to the liquid level of the injection liquid in the syringe, so that when the injection liquid is extruded to the needle part, the second stop part cooperates with the first stop part, that is, the impact force of the pushing piece on the syringe close to the needle part in the prior art is transferred to the second stop part and the first stop part, so as to avoid the weak part of the syringe, and prevent the problem of end breakage caused by the end of the syringe when the pushing piece impacts the end of the syringe with a large force.

Description

Technical Field

[0001] The present invention relates to the technical field of syringes, in particular to an automatic syringe. Background Art

[0002] The use of an automatic syringe generally involves two steps: first, remove the safety cap, then hold the syringe against the body and press down on the automatic syringe. The body reacts to the trigger mechanism of the automatic syringe, causing the trigger mechanism to release the push mechanism, which squeezes the injection liquid in the syringe barrel into the body.

[0003] Currently, the pushing mechanism includes a pushing member and a compressed first elastic member. When the pushing mechanism is released, the compressed first elastic member, under its own elastic force, pushes the pushing member, thereby squeezing the injection liquid into the body. However, because the stored force in the compressed first elastic member is constant, while the viscosity of the injection liquid varies, and to ensure that the thickest injection liquid can be squeezed into the body, the stored force in the first elastic member is generally greater than the driving force required to push the thickest injection liquid.

[0004] However, when the first elastic member is used to push a thinner injection liquid, the resistance of the injection liquid is small, and the pushing member hits the end of the syringe with a large force. Moreover, since the end of the syringe is relatively weak, the end is likely to break. Summary of the Invention

[0005] Based on this, it is necessary to propose an automatic syringe to address the problem in the prior art that when the pusher hits the end of the syringe with a large force, the end is easily broken.

[0006] An automatic injector comprising:

[0007] A syringe, comprising a syringe body and a needle portion provided at one end of the syringe body along the axial direction, wherein the syringe body is used to contain injection liquid and a first stop portion is provided on the syringe body;

[0008] The pushing mechanism includes a pushing member and a first elastic member, one end of the pushing member extends into the injection barrel, the first elastic member is used to push the pushing member to move toward the needle portion, and a second stop portion is provided on the pushing member, the first stop portion is used to stop the second stop portion to limit the movement of the pushing member toward the needle portion, and when the second stop portion abuts against the first stop portion, there is a gap between the inner wall of the injection barrel near the needle end and the pushing member.

[0009] In one embodiment, the first stop portion is arranged at an end of the syringe body away from the needle portion and is connected to the outer wall of the syringe body, and the second stop portion is a protruding structure, and the outer diameter of the protruding structure is larger than the inner diameter of the syringe.

[0010] In one embodiment, the automatic injector further includes a support sleeve and a trigger mechanism, which is sleeved outside the push member. The trigger mechanism includes a trigger pressure rod, one end of the trigger pressure rod has a rotating portion, and the trigger pressure rod is rotatably connected to the support sleeve through the rotating portion. A first limiting portion is provided on the inner side of the trigger pressure rod, and a second limiting portion is provided on the outer wall of the push member. The trigger pressure rod has a first rotation angle and a second rotation angle around the rotating portion. At the first rotation angle, the first limiting portion is engaged with the second limiting portion, and the first elastic member is in a compressed state; at the second rotation angle, the first limiting portion is away from the second limiting portion, the first limiting portion releases the second limiting portion, and the first elastic member is in a released state.

[0011] In one embodiment, either the first limiting portion or the second limiting portion is an arc-shaped protruding structure, and the other is an arc-shaped groove matched with the arc-shaped protruding structure.

[0012] In one embodiment, the trigger lever is provided with a push rod extending away from the push member, and the push rod is located near the end of the trigger lever having the rotating portion, and the trigger mechanism includes:

[0013] a movable tube assembly, one end of which is movably sleeved outside the trigger pressure rod, the movable tube assembly having a clamping position for pressing against the trigger pressure rod and a releasing position for releasing the trigger pressure rod;

[0014] a second elastic member, one end of which abuts against the movable tube assembly, and the other end of which abuts against the push rod;

[0015] When the movable tube assembly is in the engaged position, the end of the movable tube assembly away from the trigger lever is flush with the needle portion or extends outside the needle portion, the inner wall of the movable tube assembly abuts against the outer wall of the trigger lever near the needle portion, the second elastic member is in a released state, and the trigger lever is at a first rotation angle;

[0016] When the movable tube assembly is in the release position, the needle portion extends out of the movable tube assembly, the movable tube assembly releases the trigger lever close to one end of the needle portion, the second elastic member is in a compressed state, and the trigger lever is at a second rotation angle.

[0017] In one embodiment, the trigger lever has a hook portion at one end close to the needle portion that extends away from the pusher, and the movable tube assembly is provided with a release port;

[0018] When the movable tube assembly is in the engaging position, the hook abuts against the inner wall of the movable tube assembly, and the release port is located on a side of the hook close to the needle; when the movable tube assembly is in the releasing position, the hook is located in the release port.

[0019] In one embodiment, when the movable tube assembly is in the release position, the hook portion is hooked with the side wall of the release port to emit a warning sound.

[0020] In one embodiment, the mobile pipe group includes:

[0021] A protective sleeve, movably sleeved outside the injection barrel;

[0022] The limiting tube group is movably sleeved outside the trigger pressure rod, and the end of the protective sleeve away from the needle portion abuts against the limiting tube group, and the limiting tube group can be axially clamped with the supporting sleeve.

[0023] In one embodiment, the position limiting tube assembly includes:

[0024] An inner limiting sleeve, on the outer wall of which a spring block is provided, along the axial direction of the inner limiting sleeve and pointing towards the needle portion, the thickness of the spring block increases successively;

[0025] The outer limiting sleeve has an end away from the needle portion that abuts against the protective sleeve. The outer limiting sleeve has a first card interface and a second card interface that are positioned opposite to each other along its axial direction. The first card interface is closer to the needle portion than the second card interface. One end of the second elastic member abuts against the outer limiting sleeve. The second elastic member is used to push the outer limiting sleeve to move relative to the inner limiting sleeve.

[0026] The outer limiting sleeve has a first moving position and a second moving position relative to the inner limiting sleeve. When the outer limiting sleeve is in the first moving position, the elastic block is engaged with the first card interface.

[0027] When the outer limit sleeve is in the second moving position, the spring block is located in the second card interface to emit a prompt sound, the end of the spring block close to the needle portion abuts against the second card interface, and the end of the inner limit sleeve away from the needle portion abuts against the support sleeve.

[0028] In one embodiment, the automatic injector further includes a housing and a support sleeve, wherein the support sleeve is arranged in the housing, the support sleeve is arranged in the housing and on a side away from the needle portion, the first elastic member is arranged in the push member, one end of the first elastic member is against the inner wall of the push member, and the other end is against the support sleeve.

[0029] In one embodiment, a guide post is provided in the support sleeve, the guide post extends into the pushing member, and the first elastic member is sleeved on the guide post.

[0030] In one embodiment, the automatic injector further includes a housing and a protective sleeve, the syringe and the pushing mechanism are both disposed in the housing, the needle extends out of the housing, and the protective sleeve is sleeved on the housing and located at one end of the needle.

[0031] The above-mentioned automatic syringe, by arranging a first stop portion on the syringe and a second stop portion on the push member, can determine the initial distance between the first stop portion and the second stop portion according to the liquid level of the injection liquid in the syringe, so that when the injection liquid is squeezed to the needle portion, the second stop portion cooperates with the first stop portion to transfer the impact force of the push member on the syringe close to the needle portion in the prior art to between the second stop portion and the first stop portion, thereby avoiding the weak parts of the syringe and preventing the problem of the end portion being broken when the push member hits the end portion of the syringe with a large force. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is an exploded view of an automatic injector in one embodiment;

[0033] Figure 2 This is a diagram of the internal structure of the automatic injector before use (with the housing and protective cover removed);

[0034] Figure 3 is a cross-sectional view of the interior of the automatic injector before use (with the housing and protective cover removed);

[0035] Figure 4 is a cross-sectional view of the interior of the automatic injector when in use (with the housing and protective cover removed);

[0036] Figure 5 is a cross-sectional view of the interior of the automatic injector after use (with the housing and protective cover removed);

[0037] Figure 6 This is a diagram of the internal structure of the automatic injector after use (with the shell and protective cover removed).

[0038] Reference numerals: 100 - syringe; 110 - syringe body; 111 - first stopper; 120 - needle;

[0039] 200 - pushing mechanism; 210 - pushing member; 211 - second stopper; 212 - second limiting portion; 220 - first elastic member; 230 - plunger;

[0040] 300-support sleeve; 310-guide column;

[0041] 400 - trigger mechanism; 410 - trigger pressure rod; 411 - first limiting portion; 412 - push rod; 413 - hook; 430 - moving tube assembly; 431 - protective sleeve; 432 - inner limiting sleeve; 4321 - spring block; 433 - outer limiting sleeve; 4331 - first card interface; 4332 - second card interface; 440 - second elastic member;

[0042] 600-shell;

[0043] 700-Protective cover; 710-Pull-out cover; 720-Software sleeve; 730-Needle protection software. DETAILED DESCRIPTION

[0044] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0045] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0047] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0048] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0049] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0050] See Figure 1 and Figure 3 One embodiment of the present invention provides an automatic injector, comprising a syringe 100 and a push mechanism 200. The syringe 100 comprises a syringe body 110 and a needle 120 disposed at one axial end of the syringe body 110. The syringe body 110 is used to contain an injection solution, and a first stopper 111 is provided on the syringe body 110. The push mechanism 200 comprises a pusher 210 and a first elastic member 220. One end of the pusher 210 extends into the syringe 100. The first elastic member 220 is used to push the pusher 210 toward the needle 120. The pusher 210 is provided with a second stopper 211. The first stopper 111 is used to stop the second stopper 211, thereby limiting the movement of the pusher 210 toward the needle 120. When the second stopper 211 abuts the first stopper 111, a gap is formed between the inner wall of the syringe 100 near the needle 120 and the pusher 210.

[0051] By providing a first stop portion 111 on the syringe 100 and a second stop portion 211 on the push member 210, the initial distance between the first stop portion 111 and the second stop portion 211 can be determined according to the liquid level of the injection liquid in the syringe 100, so that when the injection liquid is squeezed to the needle portion 120, the second stop portion 211 cooperates with the first stop portion 111, and the impact force of the push member 210 on the syringe 100 close to the needle portion 120 in the prior art can be transferred to between the second stop portion 211 and the first stop portion 111, thereby avoiding the weak parts of the syringe 100 and preventing the problem of end rupture caused by the push member 210 hitting the end of the syringe 100 with a large force.

[0052] In some embodiments, combined Figure 4 The first stop portion 111 is arranged at one end of the syringe body 110 away from the needle portion 120 and is connected to the outer wall of the syringe body 110. The second stop portion 211 is a raised structure, and the outer diameter of the raised structure is larger than the inner diameter of the syringe 100.

[0053] In this embodiment, the first stopper 111 can be integrally manufactured with the syringe 100 and can be considered the outer flange of the syringe 100. The minimum distance between the raised structure and the outer flange should be less than the minimum distance between the pusher 210 and the inner wall of the end of the syringe 100 near the needle portion 120. When the first elastic member 220 pushes the pusher 210, causing the raised structure to move until it contacts the outer flange of the syringe 100, the second stopper 211 limits the first stopper 111, thereby preventing the end of the syringe 100 from being impacted and split.

[0054] In some embodiments, see Figure 1-Figure 3 The automatic injector also includes a housing 600 and a support sleeve 300. The support sleeve 300 is arranged in the housing 600 and on a side away from the needle portion 120. The first elastic member 220 is arranged in the push member 210. One end of the first elastic member 220 is against the inner wall of the push member 210, and the other end is against the support sleeve 300. That is, the first elastic member 220 can be used to push the push member 210 toward the needle portion, so that the push member 210 squeezes the injection liquid.

[0055] Furthermore, the pushing mechanism 200 also includes a plunger 230, which may be made of rubber. The plunger 230 is disposed within the syringe body 110 and between the needle 120 and the pushing member 210. The plunger is used to increase the airtightness between the pushing member 210 and the syringe body 110. A guide post 310 is disposed within the support sleeve 300. The guide post 310 extends into the pushing member 210. The first elastic member 220 is sleeved on the guide post 310. The guide post 310 is used to guide the movement of the first elastic member 220.

[0056] In some embodiments, see Figure 3 and Figure 4 The automatic injector further comprises a support sleeve 300 and a trigger mechanism 400. The trigger mechanism 400 is sleeved outside the pusher 210. The trigger mechanism 400 comprises a trigger pressure rod 410. One end of the trigger pressure rod 410 away from the needle portion 120 has a rotating portion. The trigger pressure rod 410 is rotatably connected to the support sleeve 300 through the rotating portion. A first limiting portion 411 is provided on the inner side of the trigger pressure rod 410. A second limiting portion 212 is provided on the outer wall of the pusher 210. The trigger pressure rod 410 has a first rotation angle (such as 0.040°) around the rotating portion. Figure 3 ) and the second rotation angle (such as Figure 4 ), at the first rotation angle, the first limiting portion 411 is engaged with the second limiting portion 212, and the first elastic member 220 is in a compressed state; at the second rotation angle, the first limiting portion 411 rotates toward the side away from the second limiting portion 212, the first limiting portion 411 releases the second limiting portion 212, and the second elastic member 440 is in a released state.

[0057] In this embodiment, the trigger mechanism 400 is used to limit the movement of the pusher 210. That is, from the production stage of the automatic injector to before use, the trigger mechanism 400 must engage the pusher 210, that is, the trigger lever 410 is always maintained at the first rotation angle. When it is needed, the trigger lever 410 rotates radially outward, that is, from the first position to the second position. At this time, the first limiting portion 411 rotates away from the second limiting portion 212, thereby causing the first limiting portion 411 to release the second limiting portion 212, that is, the pusher 210 is released, and the compressed first elastic member 220 pushes the pusher 210 to squeeze the injection liquid. The trigger lever 410 can be one or more. When there are multiple trigger levers 410, the multiple trigger levers 410 are evenly spaced around the circumference of the pusher 210.

[0058] Furthermore, one of the first limiting portion 411 and the second limiting portion 212 is a circular arc-shaped protrusion, and the other is a circular arc-shaped groove that cooperates with the circular arc-shaped protrusion. When the trigger lever rotates, the circular arc-shaped protrusion and the circular arc-shaped groove cooperate to more easily disengage from each other, thereby releasing the pusher 210.

[0059] In one of the present embodiments, the first limiting portion 411 is an arc-shaped protruding structure, and the second limiting portion 212 is an arc-shaped groove that matches the arc-shaped protruding structure.

[0060] In another embodiment, the second limiting portion 212 is an arc-shaped protruding structure, and the first limiting portion 411 is an arc-shaped groove matched with the arc-shaped protruding structure.

[0061] In some embodiments, the outer wall of the trigger lever 410 is provided with a push rod 412 extending away from the push member 210. The push rod 412 is located at one end near the rotating portion of the trigger lever 410. The trigger mechanism 400 also includes a movable tube assembly 430 and a second elastic member 440. One end of the movable tube assembly 430 is movably mounted outside the trigger lever 410. The movable tube assembly 430 has a snap-on position for pressing against the trigger lever 410 and a release position for releasing the trigger lever 410. One end of the second elastic member 440 abuts against the movable tube assembly 430, and the other end abuts against the push rod 412. When the movable tube assembly 430 is in the engaged position, the end of the movable tube assembly 430 away from the trigger lever 410 is flush with the needle 120 or extends beyond the needle 120. The inner wall of the movable tube assembly 430 abuts the outer wall of the trigger lever 410 near the needle 120. The second elastic member 440 is in a released state, and the trigger lever 410 is at a first rotation angle. When the movable tube assembly 430 is in the released position, the needle 120 extends beyond the movable tube assembly 430. The movable tube assembly 430 releases the end of the trigger lever 410 near the needle 120, the second elastic member 440 is in a compressed state, and the trigger lever 410 is at a second rotation angle.

[0062] Before use, the movable tube assembly 430 is in a locked position, and the end of the movable tube assembly 430 away from the trigger pressure rod 410 is flush with the needle portion 120, or extends outside the needle portion 120. At this time, the inner wall of the movable tube assembly 430 abuts against the outer wall of the end of the trigger pressure rod 410 close to the needle portion 120, that is, the trigger pressure rod 410 cannot rotate. During use, the user holds the housing 600 of the automatic injector, directs the side with the needle 120 toward the body, and presses downward. The movable tube assembly 430 moves upward relative to the needle 120 under the reaction of the body. When the needle 120 is inserted into the body, the movable tube assembly 430 moves upward relative to the trigger lever 410, and releases the end of the trigger lever 410 away from the rotating portion. The movable tube assembly 430 squeezes the first elastic member 220, so that the first elastic member 220 acts on the push rod 412. Since the push rod 412 is located at an end of the rotating portion close to the trigger lever 410, according to the lever principle, the trigger lever 410 rotates outward, that is, the first limiting portion 411 rotates toward the side away from the second limiting portion 212, and the push member 210 is released. At this time, the push member 210 squeezes the injection liquid into the body under the action of the compressed first elastic member 220.

[0063] Furthermore, the trigger lever 410 has a hook portion 413 on the end closest to the needle 120, extending away from the pusher 210. A release opening is provided on the movable tube assembly 430. When the movable tube assembly 430 is in the engaged position, the hook portion 413 abuts against the inner wall of the movable tube assembly 430, and the release opening is located on the side of the hook portion 413 closest to the needle 120. At this point, the trigger lever 410 is at a first rotation angle. When the movable tube assembly 430 moves upward relative to the needle 120 under the reaction of the body until the hook portion 413 is within the release opening, the movable tube assembly 430 releases the hook portion 413 of the trigger lever 410. When the trigger lever 410 rotates to the second rotation angle under the action of the second elastic member 440, the pusher 210 is released.

[0064] Specifically, when the mobile tube assembly 430 is in the engaged position, the hook portion 413 abuts against the inner wall of the mobile tube assembly 430. When the mobile tube assembly 430 switches to the released position, the mobile tube assembly 430 moves upward, and when the release opening moves to the position of the hook portion 413, the hook portion 413 hooks with the side wall of the release opening, thereby emitting a "click" sound and triggering the pressure rod 410 to rotate to the second rotation angle, releasing the pusher 210. This sound can thus notify the user that the injection of the injection liquid has begun.

[0065] In some embodiments, the movable tube assembly 430 includes a protective sleeve 431 and a limiting tube assembly. The protective sleeve 431 is movably mounted on the outside of the syringe 100. The limiting tube assembly is movably mounted on the outside of the trigger lever 410. The end of the protective sleeve 431 away from the needle 120 abuts against the limiting tube assembly, and the limiting tube assembly can cooperate with the support sleeve 300 along the axial direction.

[0066] In this embodiment, one end of the protective sleeve 431 extends to or is flush with the needle 120. Preferably, one end of the protective sleeve 431 extends beyond the needle 120 to prevent the needle 120 from accidentally damaging the device when not in use. During use, when the user presses downward, the device squeezes the protective sleeve 431 to push the stopper tube assembly. The stopper tube assembly is axially engaged with the support sleeve 300 to enhance the assembly stability of the auto-injector.

[0067] Furthermore, first stops (not labeled) are circumferentially spaced apart on the outer wall of the support sleeve 300, with the spacing between two adjacent first stops being greater than the circumferential dimension of a second stop (not labeled). Second stops are circumferentially spaced apart on the inner wall of the position-limiting tube assembly. During initial assembly, the position-limiting tube assembly is rotated so that the second stops of the position-limiting tube assembly pass through the gap between two adjacent first stops. The position-limiting tube assembly is then rotated again so that the first stops form a limiting and resisting effect on the second stops, thereby ensuring the stability of the automatic injector structure before use.

[0068] In some embodiments, see Figure 2、 Figure 5 as well as Figure 6 The limiting tube assembly includes an inner limiting sleeve 432 and an outer limiting sleeve 433. The outer wall of the inner limiting sleeve 432 is provided with an elastic block 4321, which points toward the needle portion 120 along the axial direction of the inner limiting sleeve 432. The thickness of the elastic block 4321 increases gradually. The outer limiting sleeve 433 is provided with a first locking interface 4331 and a second locking interface 4332, which are positioned opposite each other along its axial direction. The first locking interface 4331 is closer to the needle portion 120 than the second locking interface 4332. One end of a second elastic member 440 abuts against the outer limiting sleeve 433, and the second elastic member 440 is used to push the outer limiting sleeve 433 to move relative to the inner limiting sleeve 432. The outer limiting sleeve 433 has a first movable position and a second movable position relative to the inner limiting sleeve 432. When the outer limiting sleeve 433 is in the first movable position, the elastic block 4321 engages with the first locking interface 4331. When the outer limiting sleeve 433 is in the second moving position, the spring block 4321 is located in the second card interface 4332, the end of the spring block 4321 close to the needle portion 120 abuts against the second card interface 4332, and the end of the inner limiting sleeve 432 away from the needle portion 120 abuts against the support sleeve 300.

[0069] In this embodiment, before and during the injection of the automatic injector of the present application, when the outer limit sleeve 433 is always in the first moving position, refer to Figure 2 Specifically, the spring block 4321 on the inner limit sleeve 432 is always located in the first card interface 4331 of the outer limit sleeve 433, and the end of the spring block 4321 close to the needle portion 120 abuts against the inner wall of the first card interface 4331. When the protective sleeve 431 pushes the outer limit sleeve 433 upward, the outer limit sleeve 433 can push the inner limit sleeve 432 to move upward at the same time. When the trigger pressure rod 410 is at the first rotation angle, the hook portion 413 on the trigger pressure rod 410 is used to abut against the inner wall of the inner limit sleeve 432; the release port is provided on the inner limit sleeve 432. When the inner limit sleeve 432 moves upward, when the hook portion 413 of the trigger pressure rod 410 is located in the release port, the trigger pressure rod 410 rotates radially outward, and the pusher 210 is released.

[0070] When the automatic injector of the present application is completed after the injection, the user needs to pull out the needle 120 from the body. At this time, the second elastic member 440 pushes the outer limiting sleeve 433 to the side of the needle 120 under the action of its own elastic force, and the outer limiting sleeve 433 and the inner limiting sleeve 432 move relative to each other. The spring block 4321 switches from being engaged with the first card interface 4331 to being engaged with the second card interface 4332, and the outer limiting sleeve 433 switches to the second rotation angle. Figure 5 and Figure 6At this time, the spring block 4321 is used to limit the outer limiting sleeve 433 from moving toward the side away from the needle portion 120, and the supporting sleeve 300 is used to limit the inner limiting sleeve 432 from moving toward the side away from the needle portion 120, that is, the inner limiting sleeve 432, the outer limiting sleeve 433 and the protective sleeve 431 are all in a locked state, and the end of the protective sleeve 431 extends out of the needle portion 120 to prevent the trigger mechanism 400 from being accidentally pressed again, causing the needle portion 120 to accidentally damage the body.

[0071] When the outer limit sleeve 433 moves toward one end of the needle portion 120, the spring block 4321 switches from being engaged with the first card interface 4331 to being engaged with the second card interface 4332. When the spring block 4321 is engaged with the second card interface 4332, a "click" prompt sound is emitted, which can remind the user that the automatic injector has been locked.

[0072] In some embodiments, the automatic injector further includes a housing 600 and a protective cover 700 , the syringe 100 and the pushing mechanism 200 are both disposed in the housing 600 , the needle 120 extends out of the housing 600 , and the protective cover 700 is sleeved on the housing 600 and located at one end of the needle 120 .

[0073] In this embodiment, the protective cover 700 includes a pull-out cover 710, a soft sleeve 720 and a needle protection software 730 that are sequentially arranged from the outside to the inside and cooperate with each other. When in use, the pull-out cover 710 is manually pulled to pull out the soft sleeve 720 and the needle protection software 730 at the same time, and then the user can start the injection.

[0074] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. An automatic injector, characterized in that include: A syringe, comprising a syringe body and a needle portion provided at one end of the syringe body along the axial direction, wherein the syringe body is used to contain injection liquid and a first stop portion is provided on the syringe body; The pushing mechanism includes a pushing member and a first elastic member, one end of the pushing member extends into the syringe, the first elastic member is used to push the pushing member toward the needle portion, and a second stop portion is provided on the pushing member, the first stop portion is used to stop the second stop portion to limit the movement of the pushing member toward the needle portion, and when the second stop portion abuts the first stop portion, a gap is formed between the inner wall of the syringe end near the needle portion and the pushing member; The first stopper is provided at an end of the syringe body away from the needle portion and is connected to the outer wall of the syringe body; the second stopper is a raised structure, and the outer diameter of the raised structure is larger than the inner diameter of the syringe; The automatic injector further includes a support sleeve and a trigger mechanism, wherein the trigger mechanism is sleeved outside the pusher, and the trigger mechanism includes a trigger pressure rod, wherein the trigger pressure rod has a rotating portion at one end away from the needle portion, and the trigger pressure rod is rotatably connected to the support sleeve via the rotating portion, a first limiting portion is provided on the inner side of the trigger pressure rod, and a second limiting portion is provided on the outer wall of the pusher, and the trigger pressure rod has a first rotation angle and a second rotation angle about the rotating portion. At the first rotation angle, the first limiting portion is engaged with the second limiting portion, and the first elastic member is in a compressed state; At the second rotation angle, the first limiting portion rotates toward a side away from the second limiting portion, the first limiting portion releases the second limiting portion, and the first elastic member is in a released state.

2. The automatic injector according to claim 1, wherein Either one of the first limiting portion and the second limiting portion is an arc-shaped protruding structure, and the other is an arc-shaped groove matched with the arc-shaped protruding structure.

3. The automatic injector according to claim 1, wherein The trigger lever is provided with a push rod extending away from the push member, and the push rod is located at one end of the rotating portion of the trigger lever. The trigger mechanism includes: a movable tube assembly, one end of which is movably sleeved outside the trigger pressure rod, the movable tube assembly having a clamping position for pressing against the trigger pressure rod and a releasing position for releasing the trigger pressure rod; a second elastic member, one end of which abuts against the movable tube assembly, and the other end of which abuts against the push rod; When the movable tube assembly is in the engaged position, the end of the movable tube assembly away from the trigger lever is flush with the needle portion or extends outside the needle portion, the inner wall of the movable tube assembly abuts against the outer wall of the trigger lever near the needle portion, the second elastic member is in a released state, and the trigger lever is at a first rotation angle; When the movable tube assembly is in the release position, the needle portion extends out of the movable tube assembly, the movable tube assembly releases the trigger lever close to one end of the needle portion, the second elastic member is in a compressed state, and the trigger lever is at a second rotation angle.

4. The automatic injector according to claim 3, characterized in that The trigger lever has a hook portion at one end close to the needle portion that extends away from the pusher, and the movable tube assembly is provided with a release port; When the movable tube assembly is in the engaging position, the hook abuts against the inner wall of the movable tube assembly, and the release port is located on a side of the hook close to the needle; when the movable tube assembly is in the releasing position, the hook is located in the release port.

5. The automatic injector according to claim 4, characterized in that When the movable tube assembly is at the release position, the hook portion is hooked with the side wall of the release port to emit a prompt sound.

6. The automatic injector according to claim 3, characterized in that The mobile pipe group includes: A protective sleeve, movably sleeved outside the injection barrel; The limiting tube group is movably sleeved outside the trigger pressure rod, and the end of the protective sleeve away from the needle portion abuts against the limiting tube group, and the limiting tube group can be axially clamped with the supporting sleeve.

7. The automatic injector according to claim 6, characterized in that The limiting tube group includes: An inner limiting sleeve, on the outer wall of which a spring block is provided, along the axial direction of the inner limiting sleeve and pointing towards the needle portion, the thickness of the spring block increases successively; The outer limiting sleeve has an end away from the needle portion that abuts against the protective sleeve. The outer limiting sleeve has a first card interface and a second card interface that are positioned opposite to each other along its axial direction. The first card interface is closer to the needle portion than the second card interface. One end of the second elastic member abuts against the outer limiting sleeve. The second elastic member is used to push the outer limiting sleeve to move relative to the inner limiting sleeve. The outer limiting sleeve has a first moving position and a second moving position relative to the inner limiting sleeve. When the outer limiting sleeve is in the first moving position, the elastic block is engaged with the first card interface. When the outer limit sleeve is in the second moving position, the spring block is located in the second card interface to emit a prompt sound, the end of the spring block close to the needle portion abuts against the second card interface, and the end of the inner limit sleeve away from the needle portion abuts against the support sleeve.

8. The automatic injector according to claim 1, wherein The automatic injector also includes a shell and a support sleeve, wherein the support sleeve is arranged in the shell, and the support sleeve is arranged in the shell and on a side away from the needle portion. The first elastic member is arranged in the push member, and one end of the first elastic member is against the inner wall of the push member, and the other end is against the support sleeve.

9. The automatic injector according to claim 8, characterized in that A guide column is provided in the support sleeve, and the guide column extends into the pushing member. The first elastic member is sleeved on the guide column.

10. The automatic injector according to claim 1, wherein The automatic injector further comprises a housing and a protective sleeve. The injection cylinder and the pushing mechanism are both arranged in the housing. The needle extends out of the housing. The protective sleeve is sleeved on the housing and is located at one end of the needle.

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