Automatic injection pen

Abstract

This invention discloses a housing assembly and an automatic injection pen, relating to the field of automatic injectors. The housing assembly, used in an automatic injection pen, includes a housing and a protective sleeve. The inner wall of the housing has a reset surface inclined relative to the housing axis, a stop surface parallel to the housing axis, and a locking surface perpendicular to the housing axis. The protective sleeve has a locking member. When the protective sleeve moves from the distal end to the proximal end, the locking member moves along the reset surface to the nearest end of the reset surface, disengages from the reset surface, moves to the stop surface, and is limited by the locking surface, preventing the protective sleeve from moving and locking the automatic injection pen. This housing assembly improves the safety of the automatic injection pen, preventing accidental user injury.

Description

TECHNICAL FIELD

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

[0002] The automatic injection pen is used for injecting liquid medicine into the body of a recipient, and comprises a housing assembly, an injection power assembly and a needle cylinder assembly containing the liquid medicine. The injection power assembly and the needle cylinder assembly are coaxially nested inside the housing assembly, and the needle cylinder assembly is located at the side of the housing assembly close to the body of the recipient, while the injection power assembly is located at the side of the housing assembly away from the body of the recipient. The needle cylinder assembly is provided with a needle at one end and a piston at the other end. The injection power assembly provides driving force for the piston, which squeezes the liquid medicine to be injected into the human body through the needle, thus completing the injection operation of the automatic injection pen.

[0003] Most automatic injection pens are designed for one-time use, so it is crucial to protect the operator by locking the automatic injection pen after the injection operation is completed to prevent the needle from being exposed again. The locking devices for the automatic injection pen in the prior art are mostly concentrated on the injection power assembly. As the most critical component of the automatic injection pen, the injection power assembly is already complex and trivial in structure, and opening a locking structure on the injection power assembly will compress the available space of the injection power assembly. Therefore, the present application provides a locking structure on the housing assembly for locking the automatic injection pen after the injection operation is completed to prevent the needle from being exposed again due to accidental touch and hurting the operator. SUMMARY

[0004] One of the purposes of the present application is to provide a housing assembly and an automatic injection pen. The automatic injection pen using the housing assembly can not only monitor the injection process, but also ensure that the automatic injection pen is self-locked after the injection is completed to prevent the needle from being exposed again.

[0005] To achieve this purpose, the present application adopts the following technical solutions:

[0006] The housing assembly for the automatic injection pen comprises a shell and a protective sleeve. The inner wall of the shell is provided with a reset surface inclined relative to the axial direction of the shell, an abutting surface parallel to the axial direction of the shell, and a locking surface perpendicular to the axial direction of the shell. The protective sleeve is provided with a locking member. When the protective sleeve moves from the distal end to the proximal end, the locking member moves along the reset surface to the distal end of the reset surface, and then moves to the abutting surface and is limited by the locking surface. At this time, the protective sleeve cannot move, and the automatic injection pen is locked.

[0007] As a preferred solution of the housing assembly, the inner wall of the shell is provided with a self-locking boss protruding inwardly, and the reset surface, the abutting surface and the locking surface constitute the side surface of the self-locking boss.

[0008] As a preferred solution of the shell assembly, the inner wall of the shell is further provided with a trigger surface along the axial direction of the shell, and the locking member abuts against the trigger surface before the automatic injection pen is triggered for injection, and the locking member moves along the trigger surface to trigger the automatic injection pen.

[0009] As a preferred solution of the shell assembly, the protective sleeve is provided with a flexible arm, one end of the flexible arm is fixed to the body of the protective sleeve, and the other end is a free end, and the locking member is located at the free end of the flexible arm.

[0010] As a preferred solution of the shell assembly, the protective sleeve includes a cantilever and a circumferential portion, the cantilever extends along the axial direction of the protective sleeve and one end is fixed to the circumferential portion of the protective sleeve.

[0011] The cantilever includes a first side wall and a second side wall parallel to the axial direction of the shell, and a cantilever spring hook is arranged at the farthest end of the first side wall and the second side wall, and the cantilever spring hook is perpendicular to the axial direction of the first side wall and the second side wall.

[0012] As a preferred solution of the shell assembly, the inner wall of the shell is provided with a limiting boss, the limiting boss limits the limit position of the cantilever spring hook, and prevents the protective sleeve from being separated from the shell.

[0013] As a preferred solution of the shell assembly, the shell assembly further includes a cap, the cap is provided with a hook, the inner side of the circumferential portion is provided with an inner top surface, and the hook is engaged with the inner top surface to fix the cap to the protective sleeve.

[0014] As a preferred solution of the shell assembly, the cap is symmetrically provided with two extension arms, one end of the extension arm is fixed to the body of the cap, and the other end extends along the axial direction of the shell, and the distal end of the extension arm is provided with a convex portion.

[0015] As a preferred solution of the shell assembly, the automatic injection pen further includes an injection needle and a needle protection cap, the needle protection cap is located between the two extension arms, the distal end of the needle protection cap cooperates with the convex portion, and the cap is removed from the protective sleeve to drive the needle protection cap to be removed from the injection needle.

[0016] As a preferred solution of the shell assembly, the shell assembly further includes a needle cylinder protective sleeve, the needle cylinder protective sleeve includes a clamping portion, the clamping portion cooperates with a limiting portion of the shell to form a limiting assembly to limit the movement of the needle cylinder protective sleeve relative to the shell.

[0017] As a preferred solution of the shell assembly, the clamping portion includes a clamping protrusion and a clamping strip, the limiting portion includes an opening and a slot, the clamping protrusion is engaged with the opening, and the clamping strip is engaged with the slot.

[0018] As a preferred solution of the shell assembly, the needle cylinder protective sleeve is provided with a claw mounting portion near the proximal end side, one end of the claw mounting portion is fixed to the outer wall of the needle cylinder protective sleeve, one end is a free end, the free end is provided with a claw protruding towards the inner wall of the needle cylinder protective sleeve, the claw limits the limit position of the glass needle cylinder of the automatic injection pen, and prevents the glass needle cylinder from shaking in the radial direction of the automatic injection pen.

[0019] As a preferred solution of the shell assembly, the inner wall of the shell is provided with an annular table, the needle cylinder protective sleeve is provided with a limiting protrusion, and the annular table and the limiting protrusion jointly limit the limit position of the glass needle cylinder of the automatic injection pen and prevent the glass needle cylinder from moving in the axial direction of the automatic injection pen.

[0020] As a preferred solution of the shell assembly, the glass needle cylinder is provided with a flange, one side of the flange abuts against the annular table, and the other side of the flange abuts against the limiting protrusion, and the annular table and the limiting protrusion limit the movement of the flange in the axial direction of the glass needle cylinder.

[0021] As a preferred solution of the shell assembly, the automatic injection pen comprises a guide tube, and the distal end side of the guide tube is provided with a hook, the hook is engaged in the fixed hole of the shell, so that the guide tube and the shell are fixed.

[0022] As a preferred solution of the shell assembly, the shell is provided with an observation window, the observation window is adjacent to the self-locking boss in the circumferential direction of the shell, and the observation window is used for observing the injection process of the automatic injection pen.

[0023] An automatic injection pen comprises the shell assembly of any one of the above solutions.

[0024] As a preferred solution of the automatic injection pen, the automatic injection pen comprises an injection power assembly, a shell assembly and a needle cylinder assembly.

[0025] The beneficial effects of the present application are as follows:

[0026] The shell assembly of the automatic injection pen comprises a shell, a trigger surface, a reset surface and a termination surface are arranged on the inner wall of the shell, the protective sleeve moves along the trigger surface, and the automatic injection pen is triggered; after the injection of the automatic injection pen is completed, the protective sleeve moves along the reset surface until the protective sleeve is limited on the termination surface, and the automatic injection pen is locked, at this time, the automatic injection pen is blocked by the termination surface and cannot move to the distal end, that is, the automatic injection pen is locked and cannot be triggered again, and the injection needle cannot be exposed again, thereby effectively preventing personal injury caused by improper operation of the operator.

[0027] The automatic injection pen shell assembly of the present application comprises a needle cylinder protective sleeve, which is nested between a needle cylinder assembly and a protective sleeve, and a claw is arranged on the proximal end side of the needle cylinder protective sleeve, which limits the position of the proximal end of the glass needle cylinder, and after the injection operation of the automatic injection pen is completed, the contact surface of the claw contacts the end surface of the proximal end of the glass needle cylinder, the claw clamps the glass needle cylinder inward, preventing the glass needle cylinder from shaking in the radial direction during the operation of the automatic injection pen. A limiting protrusion is arranged on the distal end side of the needle cylinder protective sleeve of the shell assembly, and the inner wall of the shell body comprises an annular table, and correspondingly, the glass needle cylinder comprises a flange edge, which is limited by the annular table and the limiting protrusion, and the side surface of the flange edge close to the proximal end abuts against the annular table, and the side surface close to the distal end abuts against the limiting protrusion, the annular table and the limiting protrusion jointly prevent the flange edge from moving in the axial direction, so as to prevent the glass needle cylinder from being forced out of the shell assembly due to excessive driving force provided by the injection power assembly after the injection of the automatic injection pen is completed.

[0028] The automatic injection pen provided by the present application comprises a needle cylinder assembly, an injection power assembly and the shell assembly provided by the present application, the shell assembly is nested outside the injection power assembly and the needle cylinder assembly, which is used to prevent the needle cylinder assembly from being forced out of the automatic injection pen to cause harm to the user after the use of the automatic injection pen is completed, and is used to lock the automatic injection pen to avoid the needle being exposed again after the injection operation is completed. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is the overall schematic view of the automatic injection pen provided by the embodiment 1 of the present application;

[0030] Figure 2 is the exploded view of the automatic injection pen provided by the embodiment 1 of the present application;

[0031] Figure 3 is the longitudinal section of the automatic injection pen provided by the embodiment 1 of the present application in the initial state; Figure 1 ;

[0032] Figure 4 is the longitudinal section of the automatic injection pen provided by the embodiment 1 of the present application in the initial state; Figure 2 ;

[0033] Figure 5 is the longitudinal section of the shell structure provided by the embodiment 1 of the present application;

[0034] Figure 6 is the structure schematic of the protective sleeve provided by the embodiment 1 of the present application; Figure 1 ;

[0035] Figure 7 is the structure schematic of the protective sleeve provided by the embodiment 1 of the present application; Figure 2 ;

[0036] Figure 8is a matching view of the protective sleeve and the shell provided by embodiment 1 of the present application;

[0037] Figure 9 is a visual feedback schematic view provided by embodiment 1 of the present application;

[0038] Figure 10 is a pen cap structure schematic view provided by embodiment 1 of the present application;

[0039] Figure 11 is a pen cap removal schematic view of the auto-injection pen provided by embodiment 1 of the present application;

[0040] Figure 12 is a needle cylinder protective sleeve structure schematic view provided by embodiment 1 of the present application;

[0041] Figure 13 is a pressing injection schematic view provided by embodiment 1 of the present application;

[0042] Figure 14 is a longitudinal sectional view of the auto-injection pen in the released state provided by embodiment 1 of the present application;

[0043] Figure 15 is a longitudinal sectional view of the auto-injection pen after injection completion provided by embodiment 1 of the present application.

[0044] In the figure:

[0045] 1, bottom cover;

[0046] 2, guide tube; 201, hook;

[0047] 3, first energy storage element;

[0048] 4, release sleeve;

[0049] 5, second energy storage element;

[0050] 6, sound emitting ring;

[0051] 7, third energy storage element;

[0052] 8, push rod;

[0053] 9, needle cylinder assembly; 901, piston; 902, glass needle cylinder; 902.1, proximal end face; 902.2, flange edge; 903, injection needle; 904, needle protection cap;

[0054] 10, shell; 1001, fixed hole; 1002, observation window; 1003, limiting boss; 1003.1, distal end plane; 1004, slot; 1005, self-locking boss; 1005.1, trigger surface; 1005.2, reset surface; 1005.3, abutting surface; 1005.4, locking surface; 1006, opening; 1007, annular table;

[0055] 11, protection sleeve; 1101, circumferential part; 1101.1, inner top surface; 1102, cantilever; 1102.1, cantilever elastic hook; 1102.2, inclined surface; 1103, flexible arm; 1104, locking piece;

[0056] 12, cap; 1201, clamping hook; 1202, extension arm; 1202.1, convex part;

[0057] 13, needle cylinder protection sleeve; 1301, limiting protrusion; 1302, clamping protrusion; 1303, clamping strip; 1304, clamping jaw; 1304.1, clamping jaw contact surface;

[0058] 14, limiting ring;

[0059] 15, guide rod. DETAILED DESCRIPTION

[0060] Embodiments of the present application are described in detail below with reference to the accompanying drawings, in which the same or similar elements or elements having the same or similar functions are denoted by the same reference numerals throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0061] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0062] Unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" should be understood broadly, for example, it can be fixed connection, or detachable connection; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0063] Unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0064] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0065] like Figure 1 As shown, this embodiment provides an automatic injection pen, including an injection power assembly, a housing assembly, and a syringe assembly. The injection power assembly and the syringe assembly are located inside the housing assembly, with the syringe assembly mounted at the proximal end of the housing assembly, which is the end closest to the recipient. The injection power assembly, the syringe assembly, and the housing assembly are coaxially nested together. The injection power assembly drives the syringe assembly to inject the medication. In the following description of the schematic diagrams, unless otherwise specified, the left side of the diagram is defined as the proximal end, and the right side is defined as the distal end.

[0066] The injection power assembly includes an injection drive mechanism and a sound feedback mechanism. The injection drive mechanism provides power to the automatic injection pen to realize the injection operation of the automatic injection pen. The sound feedback mechanism provides feedback prompts to the automatic injection pen. That is, during the use of the automatic injection pen, the sound feedback mechanism emits a prompt sound to prompt the operator on the automatic operation progress.

[0067] For the structure and working principle of the injection drive mechanism, please refer to patent CN202211485881.1. This invention incorporates the injection drive mechanism into the embodiment as part of the technical solution.

[0068] Referring to patent application CN202211485881.1, the working principle of the injection driving mechanism provided in the embodiment is that by applying a force from the proximal end to the distal end to the release sleeve, the release sleeve moves from the proximal end to the distal end. When the release port of the release sleeve moves to the position of the elastic arm, the elastic arm loses the restriction of the tube wall of the release sleeve in the circumferential direction, the elastic arm expands outward, and the clamping convex located at the distal end of the elastic arm is separated from the I-shaped table and the trapezoidal table, so that the guide tube removes the movement restriction on the push rod. Since the third energy storage element needs to be reset and rebound, it will drive the push rod to move axially from the distal end to the proximal end. The I-shaped table and the trapezoidal table of the push rod move in the sliding groove of the guide tube. The push rod acts on the piston to extrude the drug liquid through the injection needle into the body of the recipient, until the push rod moves to the proximal end, the circumferential protrusion where the I-shaped table is located abuts against the side away from the proximal end of the limiting arm of the limiting ring, the effectiveness of the injection driving assembly ends, and the automatic injection operation is completed.

[0069] For the sound emitting feedback mechanism, its structure and working principle can be referred to patent CN202211485881.1. The sound emitting feedback mechanism is introduced into the embodiment as part of the technical solution.

[0070] Referring to patent application CN202211485881.1, the working principle of the sound emitting feedback mechanism provided in the embodiment is that when the injection driving assembly is in the initial state, the sound emitting feedback surface abuts against the mounting surface. As the push rod is axially moved by the release shaft, it will drive the first energy storage element and the sound emitting ring to move from the distal end to the proximal end. At this time, the sound emitting feedback surface is separated from the mounting surface, and since the first energy storage element needs to be reset and rebound, it will drive the sound emitting ring to rotate in the circumferential direction, so that the sound emitting feedback surface moves to abut against the first abutting surface of the guide surface, and a first impact sound "Dada" is emitted, prompting the recipient to start the injection. As the sound emitting ring continues to move to the proximal end, the sound emitting feedback surface continues to move along the inclined surface. The inclined surface makes the sound emitting ring rotate in the circumferential direction around the push rod, and the first energy storage element continues to store energy, until the sound emitting feedback surface moves to abut against the second abutting surface, and the first energy storage element stops storing energy. The sound emitting ring continues to move to the proximal end until the sound emitting ring moves to separate from the second abutting surface. The first energy storage element resets and rebounds, the sound emitting feedback surface abuts against the termination surface, and a second impact sound "Dada" is emitted, prompting the recipient to end the injection.

[0071] The needle cylinder assembly is composed of a piston 901, a glass needle cylinder 902, an injection needle 903, and a needle protection cap 904. The piston 901 cooperates with the injection power assembly. When the injection power assembly is triggered, the injection power assembly will drive the piston 901 to move from the distal end to the proximal end, push the drug liquid, and complete the injection operation of the automatic injection pen.

[0072] When the automatic injection pen is used, the cap 12 is removed to expose the protective sleeve 11, the nearest end of the protective sleeve 11 is placed on the injection site of the injection recipient and pressed, the protective sleeve 11 moves to the distal end, the injection needle 903 gradually exposes and penetrates into the skin, since the distal end of the protective sleeve 11 contacts the injection power assembly, the movement of the protective sleeve 11 triggers the injection power assembly, so that the injection power assembly drives the piston 901 to move and push the liquid medicine into the human body, to complete the automatic injection operation.

[0073] As shown in Figures 3-10 , the present embodiment provides a housing assembly for the automatic injection pen described above, the housing assembly includes a shell 10, a protective sleeve 11, a cap 12 and a needle cylinder protective sleeve 13, the housing assembly is nested outside the injection power assembly and the needle cylinder assembly, which is used to prevent the needle cylinder assembly from rushing out of the automatic injection pen to cause user injury after the use of the automatic injection pen is completed, and is used to lock the automatic injection pen to avoid the re-exposure of the needle after the injection operation is completed.

[0074] In the present embodiment, referring to Figure 5 , Figure 6 and Figure 8 , the inner wall of the shell 10 is provided with a reset surface 1005.2 inclined relative to the axial direction of the shell 10, an abutting surface 1005.3 parallel to the axial direction of the shell 10 and a locking surface 1005.4 perpendicular to the axial direction of the shell 10. The protective sleeve 11 is provided with a locking piece 1104, when the protective sleeve 11 moves from the distal end to the proximal end, the locking piece 1104 moves along the reset surface 1005.2 to the nearest end of the reset surface 1005.2, and then moves to the abutting surface 1005.3 and is limited by the locking surface 1005.4, so that the protective sleeve 11 cannot move, and the automatic injection pen is locked.

[0075] Specifically, the shell 10 has a hollow inner hole, the inner wall of which is provided with an inwardly protruding self-locking boss 1005, the reset surface 1005.2, the abutting surface 1005.3 and the locking surface 1005.4 constitute the side surface of the self-locking boss 1005, in addition, the self-locking boss 1005 also includes a trigger surface 1005.1 along the axial direction of the shell 10, before the automatic injection pen is started to inject, the locking piece 1104 abuts against the trigger surface 1005.1, the locking piece 1104 moves along the trigger surface 1005.1, and the automatic injection pen is triggered.

[0076] In the present embodiment, preferably, the trigger surface 1005.1 of the self-locking boss 1005 described above is inclined along the axial direction of the shell 10, of course, the trigger surface 1005.1 can also be arranged parallel to the axial direction of the shell 10, which is not specifically limited here.

[0077] The protection sleeve 11 is provided with a flexible arm 1103, one end of which is fixed on the body of the protection sleeve 11, and the other end is a free end, and the locking piece 1104 is located at the free end of the flexible arm 1103, the flexible arm 1103 extends along the axis direction of the shell 10, and the locking piece 1104 is a protrusion located at the free end of the flexible arm 1103.

[0078] Before the automatic injection pen is started to inject, the locking piece 1104 abuts against the trigger surface 1005.1, at this time, the flexible arm 1103 can be in a deformed state or in a non-deformed state, which is not specifically limited here. When the automatic injection pen is started to inject, the protection sleeve 11 is forced to move from the proximal end to the distal end, and at the same time, the locking piece 1104 abutting against the trigger surface 1005.1 is moved along the trigger surface 1005.1, and the flexible arm 1103 is deformed thereby, and when the locking piece 1104 moves to the distal end of the trigger surface 1005.1, it is separated from the trigger surface 1005.1, and the flexible arm 1103 restores the deformation. When the automatic injection pen ends the injection, the protection sleeve 11 is forced to move from the distal end to the proximal end, and at the same time, the locking piece 1104 is moved along the reset surface 1005.2, and the flexible arm 1103 is deformed again, and when the locking piece 1104 moves to the proximal end of the reset surface 1005.2, it is separated from the reset surface 1005.2 and moves to abut against the abutting surface 1005.3, and the locking piece 1104 is limited by the locking surface 1005.4, so that the protection sleeve 11 cannot move to the distal end again, and the automatic injection pen is locked, and the injection needle cannot be exposed again.

[0079] Since the automatic injection pen is disposable, the shell assembly of the embodiment is arranged to lock the automatic injection pen after the use is completed, to prevent the automatic injection pen from being triggered again by external force. Specifically, when the locking piece 1104 moves along the reset surface 1005.2 with the protection sleeve 11 moving from the distal end to the proximal end, in this process, the injection needle 903 will gradually retract into the protection sleeve 11 until the locking piece 1104 abuts against the abutting surface 1005.3, and the injection needle 903 is completely retracted into the protection sleeve 11, at this time, the locking surface perpendicular to the axis direction of the shell 10 plays a limiting role on the locking piece 1104, the protection sleeve 11 is blocked by the locking surface 1005.4 and cannot move to the distal end again, and the injection needle 903 will not be exposed again, and this process realizes the locking of the automatic injection pen, and protects the personal safety of the operator.

[0080] In the above description, it is particularly pointed out that the flexible arm 1103 can be in a non-deformation state or a deformation state when the locking piece 1104 abuts against the triggering surface 1005.1. When the flexible arm 1103 is in the non-deformation state, the locking piece 1104 just abuts against the triggering surface 1005.1, and there is no interaction force between the triggering surface 1005.1 and the locking piece 1104. When the flexible arm 1103 is in the deformation state, there is an interaction force between the triggering surface 1005.1 and the locking piece 1104, which is not specifically limited here, and both states of the flexible arm 1103 can realize the technical solution of the embodiment. In addition, the locking piece 1104 recovers deformation at the moment of disengaging from the triggering surface 1005.1. At this time, the locking piece 1104 can abut against the reset surface 1005.2 or be in an isolated state without abutting against any structure. When the locking piece 1104 abuts against the reset surface 1005.2, the flexible arm 1103 can be in a deformation state or a non-deformation state, which is not specifically limited here. When the locking piece 1104 disengages from the reset surface 1005.2 and moves to abut against the abutting surface 1005.3, the locking piece 1104 can be in a deformation state or a non-deformation state. When the locking piece 1104 is in the deformation state, there is an interaction force between the abutting surface 1005.3 and the locking piece 1104. When the locking piece 1104 is in the non-deformation state, there is no interaction force between the abutting surface 1005.3 and the locking piece 1104.

[0081] In the embodiment, continue to refer to Figures 5-8 , the shell 10 has a hollow inner hole, and the inner wall of the shell 10 is provided with a limiting boss 1003. The protective sleeve 11 is provided with a cantilever elastic hook 1102.1, and the limiting boss 1003 limits the limit position of the cantilever elastic hook 1102.1 to prevent the protective sleeve 11 from disengaging from the shell 10. Specifically, refer to Figure 5 and Figure 6 , the limiting boss 1003 can be two and symmetrical about the axis of the shell 10, and the distal end is provided with a plane. In the initial state, the cantilever elastic hook 1102.1 of the protective sleeve 11 abuts against the distal end plane of the limiting boss 1003. Due to the blockage of the plane, the cantilever elastic hook 1102.1 cannot move to the proximal end any more, and the limiting boss 1003 limits the nearest end position of the cantilever elastic hook 1102.1.

[0082] As a preferred solution of the embodiment, the protective sleeve 11 comprises a circumferential portion 1101 arranged at the proximal end and a cantilever 1102 arranged at the distal end, the cantilever 1102 extends along the axis direction of the protective sleeve 11 and is fixed at one end of the circumferential portion 1101 away from the proximal end, the other end is a free end, the number of cantilevers 1102 can be two and symmetrical about the axis of the housing 10, and each cantilever 1102 comprises a first side wall and a second side wall parallel to the axis direction of the housing 10, and the distal ends of the first side wall and the second side wall are respectively provided with a protruding cantilever elastic hook 1102.1, the cantilever elastic hook 1102.1 arranged on the first side wall extends perpendicular to the axial extension direction of the first side wall and protrudes away from the second side wall on the same cantilever 1102; the cantilever elastic hook 1102.1 arranged on the second side wall extends perpendicular to the axial extension direction of the second side wall and protrudes away from the first side wall on the same cantilever 1102.

[0083] In the assembly of the automatic injection pen of the embodiment, the protective sleeve 11 is mounted from the proximal end of the housing 10, the first side wall of one of the cantilevers 1102 moves close to one side of one of the limiting bosses 1003, and the second side wall on the same cantilever moves close to one side of the other limiting boss 1003, at this time, the two cantilever elastic hooks 1102.1 on the same cantilever are respectively limited by the limited space between the two limiting bosses 1003, the cantilever elastic hooks 1102.1 are deformed and pressed towards each other, when the cantilever elastic hooks 1102.1 move to a position not between the two limiting bosses 1003, the cantilever elastic hooks 1102.1 are no longer limited by the pressing force and recover the deformation, and the cantilever elastic hooks 1102.1 on the same cantilever abut against the distal end planes of the two limiting bosses 1003 respectively. The cantilever elastic hook 1102.1 comprises an inclined surface 1102.2 perpendicular to the first side wall and the second side wall, and the distal end of the limiting boss 1003 is provided with a distal end plane 1003.1 correspondingly, when the protective sleeve 11 is assembled and in the initial state, the inclined surface 1102.2 abuts against the distal end plane 1003.1 of the limiting boss, and the distal end plane 1003.1 limits the position of the proximal end of the cantilever elastic hook 1102.1, preventing the protective sleeve 11 from being separated from the proximal end of the housing 10 after the automatic injection pen is assembled.

[0084] In the above embodiment, the protective sleeve 11 is provided with two cantilevers 1102, and each cantilever 1102 is provided with two cantilever elastic hooks 1102.1, for the two cantilever elastic hooks 1102.1 on the same cantilever, the inclined surface 1102.2 of one of the cantilever elastic hooks 1102.1 abuts against the distal end plane 1003.1 of one of the limiting bosses 1003, and the inclined surface 1102.2 of the other cantilever elastic hook 1102.1 abuts against the distal end plane 1003.1 of the other limiting boss 1003, and the other cantilever is the same.

[0085] In the present embodiment, referring to Figure 7 , Figure 10 and Figure 11 , the inner side of the circumferential part 1101 of the protective sleeve 11 is provided with an inner top surface 1101.1, and the proximal end side of the cap 12 is provided with a hook 1201, which is engaged with the inner top surface 1101.1 to fix the cap 12 to the protective sleeve 11. Before the automatic injection pen is started to inject, the cap 12 is fixed to the circumferential part 1101 of the protective sleeve 11 to protect the automatic injection pen. When the automatic injection pen is used, the cap 12 is pulled off the circumferential part 1101 of the protective sleeve 11, and the protective sleeve 11 is pressed against the side of the body of the person receiving injection, and the automatic injection pen is triggered.

[0086] Specifically, the cap 12 is symmetrically provided with two extension arms 1202, one end of which is fixed to the body of the cap 12, and the other end extends along the axis direction of the cap 12, and the distal end of the extension arm 1202 is provided with a protrusion 1202.1. The protrusion 1202.1 on one of the extension arms 1202 is protrudingly arranged towards the other extension arm 1202, and the protrusion 1202.1 on the other extension arm 1202 is protrudingly arranged towards the one extension arm 1202. The needle protection cap 904 of the syringe assembly is located between the two extension arms 1202, and the distal end of the needle protection cap 904 cooperates with the protrusion 1202.1, and when the cap 12 is pulled off the circumferential part 1101 of the protective sleeve, the needle protection cap 904 is pulled off the injection needle 903. The needle protection cap 904 of the syringe assembly is a column structure with an open distal end and a closed proximal end, the injection needle 903 is inserted into the needle protection cap 904 from the open distal end of the needle protection cap 904, and the open distal end of the needle protection cap 904 cooperates with the protrusion 1202.1, and when the cap 12 is pulled off the protective sleeve 11, the protrusion 1202.1 moves from the distal end to the proximal end, and when the protrusion 1202.1 moves to abut against the open distal end of the needle protection cap 904, it will continue to drive the needle protection cap 904 to move from the distal end to the proximal end, thereby pulling the needle protection cap 904 off the injection needle 903, and the injection needle 903 is exposed.

[0087] As an alternative to the auto-injector pen, the housing assembly further comprises a needle cylinder protection sleeve 13 having a hollow inner hole into which the cantilever 1102 of the protection sleeve 11 extends, i.e. the needle cylinder protection sleeve is coaxially nested between the needle cylinder assembly 9 and the protection sleeve 11. The needle cylinder protection sleeve 13 is provided with an engaging portion, and the housing 10 is correspondingly provided with a limiting portion, the engaging portion of the needle cylinder protection sleeve 13 and the limiting portion of the housing 10 cooperate to form a limiting assembly to limit the movement of the needle cylinder protection sleeve 13 relative to the housing 10. Specifically, the engaging portion can be any shaped bar or protrusion or hook, and the limiting portion can be any structure capable of engaging the engaging portion therein, which is not specifically limited here.

[0088] In the present embodiment, referring to Figure 5 and Figure 12 , the engaging portion of the needle cylinder protection sleeve 13 comprises a clamping protrusion 1302 and a clamping bar 1303, and the limiting portion of the housing 10 is provided with an opening 1006 and a slot 1004, the clamping protrusion 1302 is engaged in the opening 1006, and the clamping bar 1303 is engaged in the slot 1004. Specifically, the clamping protrusion 1302 is a protruding surface perpendicular to the axis direction of the needle cylinder protection sleeve 13, and the clamping protrusion 1302 protrudes from the inner wall of the needle cylinder protection sleeve 13 to the outer wall of the needle cylinder protection sleeve 13, and the opening 1006 of the housing 10 is provided through the inner and outer walls of the housing 10, and the clamping protrusion 1302 is correspondingly engaged in the opening 1006 to fix the needle cylinder protection sleeve 13 to the housing 10 and limit the movement of the needle cylinder protection sleeve 13. The clamping bar 1303 of the needle cylinder protection sleeve 13 is provided on the side surface of the clamping protrusion 1302 close to the proximal end, and the slot 1004 of the housing 10 is provided on the inner wall of the housing 10, and the slot 1004 is not provided through, and is integrally formed with the limiting boss 1003, when the clamping protrusion 1302 is engaged in the opening 1006, the clamping bar 1303 is engaged in the slot 1004, further limiting the needle cylinder protection sleeve 13 and the housing 10 from moving axially and rotating circumferentially.

[0089] The clamping protrusion 1302 can be two and symmetrical about the axis of the needle cylinder protection sleeve 13, and the clamping bar 1303 is provided on the side surface of the clamping protrusion 1302 close to the proximal end, and also provided with two and symmetrical about the axis of the needle cylinder protection sleeve 13. Correspondingly, the opening 1006 and the slot 1004 are both provided with two and symmetrical about the axis of the housing 10.

[0090] Optionally, the needle cylinder protective sleeve 13 is provided with a claw mounting portion near the proximal end side, one end of the claw mounting portion is fixed to the outer wall of the needle cylinder protective sleeve 13, and the other end is a free end, the free end is provided with a claw 1304 protruding towards the inner wall of the needle cylinder protective sleeve 13, the claw 1304 limits the limit position of the glass cylinder 902 of the automatic injection pen, and prevents the glass cylinder 902 from shaking in the radial direction of the automatic injection pen. Specifically, the claw mounting portion is a long strip structure extending towards the proximal end from the outer wall of the needle cylinder protective sleeve, the claw 1304 is arranged at the proximal end of the free end of the claw mounting portion, and the claw 1304 includes a claw contact surface 1304.1, the glass cylinder 902 of the needle cylinder assembly 9 is coaxially nested in the hollow inner hole of the needle cylinder protective sleeve 13, and the proximal end surface 902.1 of the glass cylinder 902 abuts against the claw contact surface 1304.1, see Figure 3 , the claw 1304 limits the proximal end position of the glass cylinder 902, and because the claw 1304 protrudes towards the inner wall of the needle cylinder protective sleeve 13, the claw 1304 can clamp the glass cylinder 902 to prevent it from shaking in the radial direction of the automatic injection pen. In particular, in this embodiment, the claw mounting portion can be continuously or intermittently arranged on the outer wall of the needle cylinder protective sleeve 13, and correspondingly, the claw 1304 can also be continuously or intermittently arranged, which is not limited here.

[0091] As an optional solution of the automatic injection pen, the shell 10 has a hollow inner hole, and the inner wall of the shell 10 is provided with an annular table 1007, the annular table 1007 is integrally formed with the limiting boss 1003 and the slot 1004, the inner diameter of the annular table 1007 is smaller than the hole diameter of the hollow inner hole of the shell 10, so that there is a gap between the annular table 1007 and the inner wall of the shell 10, which can allow the cantilever 1102 of the protective sleeve 11 to move in the axial direction of the shell 10 without any obstruction.

[0092] As an optional solution of the automatic injection pen, the distal end of the needle cylinder protective sleeve is provided with a limiting protrusion 1301, the limiting protrusion 1301 is connected to the side surface of the clamping protrusion 1302 near the distal end through a connecting column, the extending direction of the limiting protrusion 1301 is parallel to the extending direction of the clamping protrusion 1302, and the limiting protrusion 1301 and the annular table in the above embodiment jointly limit the limit position of the glass cylinder 902, preventing the glass cylinder 902 from moving in the axial direction of the automatic injection pen.

[0093] Specifically, the distal end side of the glass cylinder 902 is provided with a flange 902.2, see Figure 4The flange 902.2 is perpendicular to the axis of the glass syringe 902, and extends from the inner wall of the glass syringe 902 to the outer wall of the glass syringe 902. The flange 902.2 is located between the annular platform 1007 and the limiting protrusion 1301, and one side of the flange 902.2 abuts against the annular platform 1007, and the other side of the flange 902.2 abuts against the limiting protrusion 1301. The annular platform 1007 limits the movement of the flange 902.2 to the proximal side, and the limiting protrusion 1301 limits the movement of the flange 902.2 to the distal side.

[0094] Optionally, the shell 10 comprises a fixing hole 1001, and the automatic injection pen comprises a guide tube 2, and the guide tube 2 is provided with a hook 201 at the distal side of the guide tube 2, and the hook 201 is engaged with the fixing hole 1001, so as to fix the guide tube 2 and the shell 10. Specifically, the fixing hole 1001 is arranged at the distal side of the shell 10 and penetrates the inner and outer walls of the shell 10, and the hook 201 is a protrusion arranged at the distal side of the guide tube 2. The structure of the hook 201 is matched with the fixing hole 1001. Preferably, the shape of the hook 201 is arranged to facilitate engagement with the fixing hole 1001 and not easy to be separated from the fixing hole 1001. The embodiment is not limited specifically.

[0095] As an optional solution of the automatic injection pen, the shell 10 is provided with an observation window 1002 arranged through the inner and outer walls of the shell 10. The observation window 1002 is adjacent to the self-locking boss 1005 in the circumferential direction of the shell 10, and the observation window 1002 is used to observe the injection process of the automatic injection pen. The observation window 1002 is arranged at a position close to the proximal side of the shell 10. See Figure 4 、 Figure 5 and Figure 9 When the automatic injection pen is in the injection process, the piston 901 moves proximally in the glass syringe 902. The operator can observe the relative position of the piston 901 in the observation window 1002, so as to facilitate the judgment of the injection process of the automatic injection pen.

[0096] The working principle of the shell assembly provided in the embodiment is as follows:

[0097] In use of the automatic injection pen, first, the cap 12 is pulled out, exposing the circumferential part 1101 of the protective sleeve 11, the circumferential part 1101 of the protective sleeve 11 is pressed against the skin surface of the injection recipient, the protective sleeve 11 is moved from the proximal end to the distal end relative to the housing 10, driving the trigger sleeve 4 to move from the proximal end to the distal end, the injection needle 903 gradually extends out of the protective sleeve 11 and penetrates into the skin, the automatic injection pen is triggered to switch to the injection state; at the same time, the locking member 1104 moves along the trigger surface 1005.1, the flexible arm 1103 is deformed, when the locking member 1104 moves to the distal end of the trigger surface 1005.1, the locking member 1104 is separated from the trigger surface 1005.1, and the flexible arm 1103 restores the deformation. When the automatic injection pen is completed, the protective sleeve 11 moves from the distal end to the proximal end, the locking member 1104 moves along the reset surface 1005.2, when the locking member 1104 moves to the proximal end of the reset surface 1005.2, the locking member 1104 is separated from the reset surface 1005.2 and moves to abut against the surface 1005.3, at this time, the distal end side of the locking member 1104 is blocked by the locking surface 1005.4, the protective sleeve 11 cannot move to the distal end again, and the automatic injection pen is locked, the injection needle cannot be exposed again.

[0098] The above is only the preferred embodiment of the present application, for those skilled in the art, according to the idea of the present application, the specific implementation and application range can be changed, the content of the description should not be understood as the limitation of the present application.

Claims

1. An auto-injector pen comprising an injection power assembly, a housing assembly, the injection power assembly located inside the housing assembly; the injection power assembly comprising an injection drive mechanism and a sound emitting feedback mechanism, the housing assembly comprising a housing, a protective sleeve, characterized in that, The inner wall of the shell is provided with a reset surface inclined relative to the shell axis direction, an abutting surface parallel to the shell axis direction, and a locking surface perpendicular to the shell axis direction; the protective sleeve is provided with a locking member, when the protective sleeve moves from the distal end to the proximal end, the locking member moves along the reset surface, and when the reset surface is at the proximal end, the locking member is separated from the reset surface and moves to the abutting surface and is limited by the locking surface, so that the protective sleeve cannot move, and the automatic injection pen is locked; The injection driving mechanism comprises a guide tube and a push rod, the push rod only has axial movement before the automatic injection pen is triggered and after the use of the automatic injection pen is completed; the guide tube has a first sliding groove, and the push rod has an engaging block which moves axially along the first sliding groove to limit the rotation of the push rod; The sound generating feedback mechanism comprises a sound generating ring and a sound generating feedback assembly; the sound generating feedback assembly comprises a guide surface and a terminal surface provided on the wall of the guide tube, and the guide surface comprises a first abutting surface; the axial movement of the push rod drives the sound generating ring to collide with the first abutting surface to generate a starting prompt sound; the axial movement of the push rod drives the sound generating ring to collide with the terminal surface to generate a terminal prompt sound.

2. The auto-injector pen of claim 1, wherein, The inner wall of the shell is provided with an inwardly protruding self-locking boss, and the reset surface, the abutting surface and the locking surface constitute the side surfaces of the self-locking boss.

3. The auto-injector pen of claim 1, wherein, The inner wall of the shell is further provided with a trigger surface along the shell axis direction, and before the automatic injection pen is triggered, the locking member abuts against the trigger surface, the locking member moves along the trigger surface, and the automatic injection pen is triggered.

4. The auto-injector pen of claim 1, wherein, The protective sleeve is provided with a flexible arm, one end of the flexible arm is fixed to the body of the protective sleeve, and the other end is a free end, and the locking member is located at the free end of the flexible arm.

5. The auto-injector pen of claim 4, wherein, The protective sleeve comprises a cantilever and a circumferential portion, the cantilever extends along the axis direction of the protective sleeve and one end of the cantilever is fixed to the circumferential portion of the protective sleeve.

6. The auto-injector pen of claim 5, wherein, The cantilever comprises a first side wall and a second side wall parallel to the axis direction of the shell, and a cantilever elastic hook is arranged at the distal end of the first side wall and the second side wall, and the cantilever elastic hook is perpendicular to the axis direction of the first side wall and the second side wall.

7. The auto-injector pen of claim 6, wherein, The inner wall of the shell is provided with a limiting boss, the limiting boss limits the extreme position of the cantilever elastic hook, and prevents the protective sleeve from being separated from the shell.

8. The auto-injector pen of claim 5, wherein, The shell assembly further comprises a pen cap, the pen cap is provided with a hook, the inner side of the circumferential portion is provided with an inner top surface, and the hook is engaged with the inner top surface to fix the pen cap to the protective sleeve.

9. The auto-injector pen of claim 8, wherein, The pen cap is symmetrically provided with two extension arms, one end of the extension arm is fixed to the body of the pen cap, the other end extends along the axis direction of the shell, and the distal end of the extension arm is provided with a convex portion.

10. The auto-injector pen of claim 9, wherein, The automatic injection pen further comprises an injection needle and a needle protection cap, the needle protection cap is located between the two extension arms, the distal end of the needle protection cap cooperates with the convex portion, and the pen cap is removed from the protective sleeve to drive the needle protection cap to be removed from the injection needle.

11. The auto-injector of claim 1, wherein, The shell assembly further comprises a needle cylinder protective sleeve, the needle cylinder protective sleeve comprises a clamping portion, the clamping portion cooperates with a limiting portion of the shell to form a limiting assembly to limit movement of the needle cylinder protective sleeve relative to the shell.

12. The auto-injector of claim 11, wherein, The clamping portion comprises a clamping protrusion and a clamping strip, the limiting portion comprises an opening and a slot, the clamping protrusion is clamped in the opening, and the clamping strip is clamped in the slot.

13. The auto-injector of claim 11, wherein, The needle cylinder protective sleeve is provided with a clamping jaw mounting portion near the proximal end side, one end of the clamping jaw mounting portion is fixed to the outer wall of the needle cylinder protective sleeve, and the other end is a free end, the free end is provided with a clamping jaw protruding towards the inner wall of the needle cylinder protective sleeve, the clamping jaw limits the limit position of the glass needle cylinder of the automatic injection pen, and prevents the glass needle cylinder from shaking in the radial direction of the automatic injection pen.

14. The auto-injector of claim 11, wherein, The inner wall of the shell is provided with an annular table, the needle cylinder protective sleeve is provided with a limiting protrusion, and the annular table and the limiting protrusion jointly limit the limit position of the glass needle cylinder of the automatic injection pen and prevent the glass needle cylinder from moving in the axial direction of the automatic injection pen.

15. The auto-injector of claim 14, wherein the needle guard is configured to move from the first position to the second position when the plunger reaches the end of the injection stroke. The glass needle cylinder is provided with a flange, one side of the flange abuts against the annular table, and the other side of the flange abuts against the limiting protrusion, and the annular table and the limiting protrusion limit movement of the flange in the axial direction of the glass needle cylinder.

16. The auto-injector of claim 1, wherein, The distal end side of the guide tube is provided with a clamping hook, the clamping hook is clamped in the fixed hole of the shell, so as to realize fixation of the guide tube and the shell.

17. The auto-injector of claim 2, wherein, The shell is provided with an observation window, the observation window is adjacent to the self-locking boss in the circumferential direction of the shell, and the observation window is used to observe the injection process of the automatic injection pen.

Images