Dose adjusting mechanism of injection device and injection device

Abstract

The invention relates to the technical field of medical instruments, in particular to a dose adjusting mechanism of an injection device and the injection device. A push rod part penetrates through a holding part and is in threaded connection with the holding part, a sound tooth part sleeves the push rod part and is in circumferential limiting connection with the push rod part, and the push rod part can move in the axial direction relative to the sound tooth part; one-way clamping grooves distributed in the circumferential direction are formed in the circumferential wall defining the containing cavity, the sound tooth part is located in the containing cavity, the sound tooth part is provided with an elastic clamping part, and the elastic clamping part is clamped into any one of the one-way clamping grooves; under the state that the push rod part is pressed, the push rod part can move in the axial direction and drive the sound tooth part to rotate synchronously under the action of the threads, so that the elastic clamping part slides along the peripheral wall defining the containing cavity to be clamped into one of the one-way clamping grooves in the front end. Axial control of the push rod part is converted into rotation control of the sound tooth part, rotation movement of the sound tooth part is discretized into fixed angle grading, the axial displacement of single-time grading of the push rod part is extremely small, and the small-dose injection requirement is met.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and particularly to a dose adjustment mechanism and an injection device of an injection device. Background Art

[0002] The related art injection device includes an outer sleeve component, a push rod component, and a cartridge component. The surface of the push rod component has a concave-convex structure continuously distributed along the axial direction. The push rod component is adapted to be sleeved with the outer sleeve component and move along the axial direction of the outer sleeve component. The concave-convex structure is blocked by the cartridge component during the movement of the push rod component. The cartridge component is arranged at the opening of the first end where the push rod component is sleeved with the outer sleeve component, and is adapted to cooperate with the concave-convex structure on the push rod component to block the movement of the push rod component during the axial movement of the push rod component along the outer sleeve component. The distance between adjacent concave-convex structures has a corresponding relationship with the dose of the injection substance. With the cooperation of the concave-convex structure and the cartridge component, by blocking the movement of the push rod component, the dose of the injection substance can be accurately controlled, and the accuracy of the injection amount of the injection substance can be improved.

[0003] In the related art injection device, the spacing between adjacent concave-convex structures determines the minimum dose unit. If a smaller dose is to be achieved, the spacing between adjacent concave-convex structures needs to be shortened. However, limited by processing precision such as machining ability, too small a spacing may cause the concave-convex structure to be unable to be stably formed or be easily worn, resulting in the related art injection device being only suitable for large-dose injections and unable to meet the requirements of small-dose injections. Summary of the Invention

[0004] The purpose of the present application is to provide a dose adjustment mechanism and an injection device of an injection device to solve the problem of being unable to meet the requirements of small-dose injections.

[0005] To solve the above technical problems, the present application provides a dose adjustment mechanism of an injection device, including a push rod part, a holding part, and a click part. The push rod part passes through the holding part and is threadedly connected. The click part is sleeved on the push rod part and is circumferentially limited and connected. The push rod part can move axially relative to the click part. The holding part has a receiving cavity, and the circumferential wall enclosing the receiving cavity is provided with one-way card slots distributed along the circumferential direction. The click part is located in the receiving cavity, and the click part has an elastic clamping part, and the elastic clamping part is snapped into any one of the one-way card slots.

[0006] In a state where the push rod part is subjected to a pressing force, the push rod part can move axially and drive the click part to rotate synchronously under the action of the thread, so that the elastic clamping part slides along the circumferential wall enclosing the receiving cavity to be snapped into one of the front one-way card slots.

[0007] Optionally, the circumferential wall enclosing the receiving cavity is provided with a plurality of ratchet teeth distributed along the circumferential direction. An intermediate space is formed between adjacent ratchet teeth, and the intermediate space is the one-way card slot.

[0008] Optionally, a limiting groove is provided on the outer peripheral wall of the push rod portion, the limiting groove extends along the axial direction of the push rod portion, the sound tooth portion is provided with a limiting protrusion, and at least a part of the limiting protrusion is slidably inserted into the corresponding limiting groove.

[0009] Optionally, the push rod portion has a pressing end, and an installation groove is provided on the end wall of the holding portion facing away from the pressing end, and the installation groove is used for laterally limiting and installing a protruding portion at the open end of the barrel of the injection device;

[0010] The dose adjustment mechanism further includes a blocking member, the blocking member is connected to the holding portion, and the blocking member is configured to abut against the end wall of the protruding portion facing away from the pressing end to axially limit the protruding portion.

[0011] Optionally, the end of the holding portion facing away from the pressing end includes two oppositely arranged mounting portions, the opposite end walls of the two mounting portions form part of the inner wall of the mounting groove, the holding portion is further provided with a mounting hole that laterally penetrates the two mounting portions, the mounting hole communicates with the mounting groove, and part of the blocking member is fixedly installed in the mounting hole.

[0012] Optionally, the blocking member includes a blocking member body, the blocking member body is provided with a notch groove with an open first end and at least one avoidance opening, the blocking member further includes at least one elastic member, the first end of the elastic member is connected to the inner wall surrounding the avoidance opening, in the non-loaded state, the second end of the elastic member extends obliquely away from the pressing end, and the length of the elastic member is not greater than the length between the first end and the second end of the avoidance opening;

[0013] In the connection state of the dose adjustment mechanism and the barrel, both ends of the blocking member are inserted into the mounting hole, the barrel passes through the notch groove, the closed end wall surrounding the notch groove abuts against the outer wall of the barrel, and the end wall of the second end of the elastic member abuts against the wall portion surrounding the mounting groove.

[0014] Optionally, the portions of the blocking member body on both sides in the width direction of the notch groove are blocking arms, among the two mounting portions, the mounting portion close to the first end is the first mounting portion, and the mounting portion close to the second end is the second mounting portion;

[0015] The mounting hole includes two first holes provided in the first mounting portion and a second hole provided in the second mounting portion, the first end of the blocking arm is inserted into the corresponding first hole, and the second end of the blocking member body is inserted into the second hole.

[0016] Optionally, the holding portion includes:

[0017] The body part, the body part has a receiving groove, one end of the receiving groove close to the pressing end of the push rod part is an open end, and a one-way card slot is arranged on the peripheral wall surrounding the receiving groove;

[0018] The cover plate part, the cover plate part is connected to the open end of the body part, and the receiving groove forms at least part of the receiving cavity.

[0019] Optionally, the body part includes a first cylinder body arranged inside the receiving groove, the end wall surrounding the receiving groove has a through hole communicating with the first cylinder body, and the push rod part passes through the first cylinder body and is threadedly connected;

[0020] The rattling tooth part includes a second cylinder body, the elastic clamping part is connected to the outer peripheral wall of the second cylinder body, one end of the second cylinder body close to the cover plate part has a folded part that turns inward, the second cylinder body is movably sleeved on the first cylinder body, and the end wall of the folded part facing away from the cover plate part abuts against the opposite end of the first cylinder body.

[0021] Optionally, the push rod part has a pressing end, and the dose adjustment mechanism further includes a pressing part, and the pressing part is rotatably connected to the pressing end.

[0022] This application also provides an injection device, which is characterized in that it includes:

[0023] A cylinder body, having an injection end and an open end;

[0024] A sealing plug, slidably arranged inside the cylinder body. Taking the sealing plug as a boundary, the area inside the cylinder body close to the injection end forms a storage cavity, and the storage cavity is used for storing the injection substance;

[0025] The dose adjustment mechanism of the aforementioned injection device, the holding part of the dose adjustment mechanism is connected to the open end of the cylinder body, and the push rod part of the dose adjustment mechanism is connected to the sealing plug.

[0026] The technical effects of this application are as follows:

[0027] The dose adjustment mechanism of this application, through the precise thread fit between the push rod part and the holding part, and the circumferential limit connection between the push rod part and the rattling tooth part, converts the axial displacement control of the push rod part into the rotational motion control of the rattling tooth part. At the same time, through the clamping cooperation between the circumferentially distributed one-way card slots and the elastic clamping parts, the rotational motion of the rattling tooth part is discretized into fixed-angle sub-files. By matching the thread pitch and the number of one-way card slots, the single-step sub-file axial displacement of the push rod part is extremely small, meeting the small-dose injection requirements. Description of the Drawings

[0028] Figure 1 It is a schematic structural diagram of a specific embodiment of the dose adjustment mechanism provided by this application;

[0029] Figure 2 is Figure 1 Schematic diagram of the structure when the cover plate part of the dose adjustment mechanism is removed;

[0030] Figure 3 is the axial sectional view of a specific embodiment of the injection device provided by the present application;

[0031] Figure 4 is Figure 1 Schematic diagram of the structure of the ratchet part in the dose adjustment mechanism;

[0032] Figure 5 is Figure 3 Schematic diagram of the structure of the holding part, the blocking part and the barrel in the injection device;

[0033] Figure 6 is Figure 5 Schematic diagram of the structure of the holding part and the blocking part in;

[0034] Figure 7 is Figure 6 Schematic diagram of the structure of the holding part in;

[0035] Figure 8 is Figure 6 Schematic diagram of the structure of the blocking part in;

[0036] Figure 9 is Figure 1 Schematic diagram of the structure of the holding part in the dose adjustment mechanism;

[0037] Figure 10 is Figure 9 Schematic diagram of the structure of the main body part in;

[0038] Figure 11 is Figure 9 Schematic diagram of the structure of the cover plate part in;

[0039] Figure 12 is Figure 1 Partial sectional view of the dose adjustment mechanism;

[0040] Figure 13 is Figure 1 Schematic diagram of the structure of the push rod part and the pressing part in the dose adjustment mechanism;

[0041] Among them, Figures 1 - 13 the reference numerals in are as follows:

[0042] 100 - dose adjustment mechanism;

[0043] 101 - push rod part;

[0044] 102 - Holding part; 102-1 - Body part; 102-1a - Accommodating groove; 102-11 - First cylinder; 102-12 - Protrusion; 102-2 - Cover plate part; 102a - Accommodating cavity; 102b - One-way card slot; 102c - Installation groove; 102d - Installation hole; 102d-1 - First hole; 102d-2 - Second hole; 1021 - Ratchet teeth; 1022 - Ratchet tooth groove; 1023 - Installation part; 1023-1 - First installation part; 1023-2 - Second installation part;

[0045] 103 - Rattling tooth part; 1031 - Elastic clamping part; 1032 - Second cylinder; 1032-1 - Folding part;

[0046] 104 - Blocking part; 1041 - Blocking part body; 1041a - Notch groove; 1041b - Avoidance opening; 10411 - Blocking arm; 1042 - Elastic part;

[0047] 105 - Pressing part;

[0048] a - Limiting groove; b - Limiting protrusion; c - Buckle; d - Clamping groove; e - Positioning hole; f - Positioning post;

[0049] 200 - Cylinder; 201 - Protruding part; 200a - Storage cavity;

[0050] 300 - Sealing plug. Detailed implementation manners

[0051] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0052] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / ", generally represents an "or" relationship between the associated objects before and after.

[0053] It should be understood that the "some embodiments" mentioned throughout the specification mean that the specific features, structures or characteristics related to the embodiments are included in at least one embodiment of the present application. Therefore, the "in some embodiments" that appears throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner.

[0054] In the description herein, unless otherwise clearly specified and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this article can be understood according to specific situations.

[0055] Please refer to Figures 1 - 3 , Figure 1 is a schematic structural diagram of a specific embodiment of the dose adjustment mechanism provided by the present application; Figure 2 is Figure 1 a schematic structural diagram of the dose adjustment mechanism when the cover part is removed; Figure 3 is an axial sectional view of a specific embodiment of the injection device provided by the present application.

[0056] The dose adjustment mechanism 100 of an injection device provided by an embodiment of the present application includes a push rod part 101, a holding part 102 and a ratchet part 103. The push rod part 101 passes through the holding part 102 and is threadedly connected. The ratchet part 103 is sleeved on the push rod part 101 and is circumferentially limited and connected. The push rod part 101 can move axially relative to the ratchet part 103. The holding part 102 has a receiving cavity 102a. The circumferential wall surrounding the receiving cavity 102a is provided with circumferentially distributed one-way card slots 102b. The ratchet part 103 is located in the receiving cavity 102a. The ratchet part 103 has an elastic clamping part 1031, and the elastic clamping part 1031 is snapped into any one of the one-way card slots 102b;

[0057] In a state where the push rod part 101 is subjected to a pressing force, the push rod part 101 can move axially, and under the action of the thread, drive the ratchet part 103 to rotate synchronously, so that the elastic clamping part 1031 slides along the circumferential wall surrounding the receiving cavity 102a to be snapped into one of the one-way card slots 102b at the front end.

[0058] Figure 2 The direction of the arrow shown is the rotation direction of the ratchet part 103, that is, the sliding direction of the elastic clamping part 1031 along the circumferential wall surrounding the receiving cavity 102a. The front end mentioned here refers to the end pointed by the sliding direction of the elastic clamping part 1031. As Figure 3As shown, the injection device generally further includes a barrel 200 and a sealing plug 300. The barrel 200 has an injection end and an open end. The sealing plug 300 is slidably disposed inside the barrel 200. Taking the sealing plug 300 as a boundary, the area inside the barrel 200 near the injection end forms a storage cavity 200a for storing the injection material. When the dose adjustment mechanism 100 of the embodiment of the present application is applied to the injection device, the holding part 102 is connected to the open end of the barrel 200 and can be held by an operator, so that the holding part 102 and the barrel 200 are in a fixed state. The push rod part 101 passes through the holding part 102 and is connected to the sealing plug 300. The push rod part 101 is threadedly connected to the holding part 102. When the holding part 102 is held by the operator and the push rod part 101 is under a pressing force, the push rod part 101 can move axially and rotate under the action of the thread; the ratchet part 103 is sleeved on the push rod part 101 and is circumferentially limited and connected. The push rod part 101 can move axially relative to the ratchet part 103. The holding part 102 has a receiving cavity 102a, and the ratchet part 103 is located in the receiving cavity 102a, that is, the ratchet part 103 can rotate synchronously with the rotation of the push rod part 101, and the ratchet part 103 does not hinder the axial movement of the push rod part 101; when the thread pitch of the push rod part 101 and the holding part 102 is fixed, the rotation angle of the ratchet part 103 (push rod part 101) strictly corresponds to the axial displacement of the push rod part 101. For example, when the thread pitch of the push rod part 101 and the holding part 102 is 1 mm, when the ratchet part 103 (push rod part 101) rotates 360°, the push rod part 101 moves 1 mm axially, so as to ensure that the dose is controllable; the circumferential wall surrounding the receiving cavity 102a is provided with circumferentially distributed one-way card slots 102b, and the ratchet part 103 has an elastic clamping part 1031, and the elastic clamping part 1031 is snapped into any one of the one-way card slots 102b; thus, the circumferentially distributed one-way card slots 102b discretize the circumferential movement of the ratchet part 103. When the push rod part 101 is under a pressing force, the push rod part 101 moves axially and drives the ratchet part 103 to rotate synchronously under the action of the thread. The elastic clamping part 1031 gradually slides out of the current one-way card slot 102b along the circumferential wall surrounding the receiving cavity 102a and is snapped into the next one-way card slot 102b. Every time the elastic clamping part 1031 slides past a one-way card slot 102b, the push rod part 101 moves a fixed distance. It can be seen that each one-way card slot 102b corresponds to one gear. By designing the number of the one-way card slots 102b, each one-way card slot 102b can correspond to a clear dose unit. For example, when the thread pitch of the push rod part 101 and the holding part 102 is 1 mm, the circumferential wall surrounding the receiving cavity 102a is provided with 12 one-way card slots 102b, and the interval between adjacent one-way card slots 102b is 30°. Every time the ratchet part 103 slides past a one-way card slot 102b, the moving distance of the push rod part 101 is the ratio of the thread pitch to the number of one-way card slots, that is, approximately 0.0833mm, breaking through the single minimum injection volume limit of the traditional axial concave-convex structure, meeting the needs of small-dose injection.

[0059] Among them, in the process that the elastic clamping part 1031 gradually slides out of the current one-way clamping slot 102b, the elastic clamping part 1031 is squeezed and deformed, and the elastic clamping part 1031 gradually accumulates energy; when the elastic clamping part 1031 passes over the current one-way clamping slot 102b, the elastic potential energy of the elastic clamping part 1031 is released, and the elastic clamping part 1031 instantly bounces into the next one-way clamping slot 102b. The collision between the elastic clamping part 1031 and the surrounding wall surrounding the accommodating cavity 102a will produce a "click" sound, or cause the push rod part 101 to produce a slight vibration. When the user hears the "click" sound or senses the vibration, it indicates that the injection of one dosage unit is completed. The user can accurately control the total injection volume by counting the number of "click" sounds or the number of vibrations, so as to avoid injection errors as much as possible.

[0060] The aforementioned one-way slot 102b means that when the push rod portion 101 is subjected to pressing force, the elastic clamping portion 1031 can only slide one-way along the peripheral wall surrounding the accommodating cavity 102a to be clamped into the one-way slot 102b at the front end, but cannot slide in the opposite direction, i.e., it ensures that the tooth portion 103 can only rotate one-way, but not in the opposite direction, thereby ensuring that the push rod portion 101 and the sealing plug 300 can only move one-way under the action of pressing force, but cannot move in the opposite direction. On the one hand, it improves the accuracy of the injection amount and avoids injection errors as much as possible; on the other hand, it avoids the secondary use of the dosage adjustment mechanism 100, meets the anti-reuse requirements of disposable medical devices, reduces the risk of cross infection, and improves safety.

[0061] To summarize, the dose adjustment mechanism 100 of the embodiment of the present application converts the axial displacement control of the push rod portion 101 into the rotational motion control of the tooth portion 103 through the precise threaded cooperation between the push rod portion 101 and the grip portion 102, and the circumferential limiting connection between the push rod portion 101 and the tooth portion 103. At the same time, the rotational motion of the tooth portion 103 is discretized into fixed angle steps through the clamping cooperation of the circumferentially distributed one-way slots 102b and the elastic clamping portion 1031. By matching the thread pitch and the number of one-way slots, the single-step axial displacement of the push rod portion 101 is extremely small, thereby meeting the needs of small-dose injection.

[0062] like Figure 2 As shown, in some embodiments of the present application, the peripheral wall surrounding the accommodating cavity 102a is provided with a plurality of ratchet teeth 1021 distributed along the circumferential direction, and ratchet grooves 1022 are formed between adjacent ratchet teeth 1021, and the ratchet grooves 1022 are the aforementioned one-way slots 102b.

[0063] The wall surface of the ratchet 1021 has a blocking surface and an inclined surface, and the inclined surface also forms a guiding surface. In a state where the push rod portion 101 is subjected to a pressing force, the elastic clamping portion 1031 can slide along the inclined surface, so as to smoothly slide over the top of the current ratchet 1021 and fall into the next ratchet groove 1022. The inclined surface can reduce the resistance of the forward operation and improve the operation convenience; when the elastic clamping portion 1031 slides over the top of the current ratchet 1021 and falls into the next ratchet groove 1022, a clear "click" sound and / or operation feeling (such as slight vibration) is usually generated, giving the user a clear feedback that the unit-dose injection is completed; during the reverse operation, the blocking surface of the ratchet 1021 will block the elastic clamping portion 1031, ensuring that the push rod portion 101 and the sealing plug 300 cannot move in the reverse direction, as much as possible avoiding injection errors, and preventing the dose adjustment mechanism 100 from being reused, improving safety. Moreover, the shape of the ratchet 1021 is relatively standard, which is convenient for manufacturing by means of machining, stamping, casting or injection molding, etc., improving the forming convenience and reducing the production cost.

[0064] Please refer to Figure 2 and Figure 4 , Figure 4 for Figure 1 the schematic structural view of the click part in the dose adjustment mechanism.

[0065] In the embodiment of the present application, the click part 103 has two elastic clamping portions 1031, and the two elastic clamping portions 1031 are arranged at intervals in the circumferential direction. The one-way locking is realized by the cooperation of the two elastic clamping portions 1031 and the ratchet 1021, which is beneficial to dispersing the load, improving the bearing capacity of the dose adjustment mechanism 100 in the embodiment of the present application, and enhancing the locking accuracy of the push rod portion 101 and the sealing plug 300. In some other embodiments of the present application, the click part 103 has at least one elastic clamping portion 1031.

[0066] Among them, the elastic clamping portion 1031 is made of a material that can generate elastic deformation, such as plastic with certain elasticity.

[0067] As described above, the push rod portion 101 and the click part 103 are circumferentially limited and connected, and the push rod portion 101 can move axially relative to the click part 103. Specifically, in this embodiment, as Figure 2 shown, a limiting groove a is provided on the outer peripheral wall of the push rod portion 101, the limiting groove a extends along the axial direction of the push rod portion 101, the click part 103 is provided with a limiting protrusion b, and at least part of the limiting protrusion b is slidably inserted into the corresponding limiting groove a.

[0068] As configured above, the limiting groove a can play a role in limiting and guiding the limiting protrusion b, and the two side walls in the width direction of the limiting protrusion b and the two side walls in the width direction of the limiting groove a can adopt a transition fit. On the one hand, the limiting groove a can reliably limit the limiting protrusion b along the width direction, and avoid relative shaking of the push rod part 101 and the ring tooth part 103 along the circumferential direction as much as possible, thereby improving the injection accuracy; on the other hand, the limiting protrusion b can slide more smoothly along the extension direction of the limiting groove a, thereby reducing the operating resistance and improving the operating convenience.

[0069] In addition, the limiting groove a is set on the push rod part 101, and the limiting protrusion b is set on the snap tooth part 103, which can also avoid interference with the threaded cooperation between the push rod part 101 and the grip part 102, thereby ensuring the normal operation of the dose adjustment mechanism 100 of the embodiment of the present application.

[0070] Depend on Figure 4 It can be seen that in the embodiment of the present application, the snapping tooth portion 103 includes two oppositely arranged limiting protrusions b; correspondingly, the push rod portion 101 includes two oppositely arranged limiting grooves a. The plug-in cooperation of the two sets of limiting protrusions b and the limiting grooves a is beneficial to dispersing the load and further improving the limiting reliability of the snapping tooth portion 103 on the push rod portion 101.

[0071] In some other embodiments of the present application, the rattling tooth portion 103 has at least one limiting protrusion b, and the push rod portion 101 has at least one limiting groove a.

[0072] Please refer to Figures 5 - 6 , Figure 5 for Figure 3 A schematic diagram of the structure of the gripping part, the blocking member and the barrel in the injection device; Figure 6 for Figure 5 Schematic diagram of the structure of the gripping portion and the blocking member in the dose adjustment mechanism.

[0073] In the embodiment of the present application, the push rod portion 101 has a pressing end, and the end wall of the grip portion 102 facing away from the pressing end is provided with a mounting groove 102c, and the mounting groove 102c is used to install the protrusion 201 located at the open end of the barrel 200 of the injection device in a transverse limited manner;

[0074] The dose adjustment mechanism 100 further includes a blocking member 104 , which is connected to the gripping portion 102 . The blocking member 104 is configured to abut against an end wall of the protruding portion 201 facing away from the pressing end to limit the axial position of the protruding portion 201 .

[0075] The axial direction is defined as the extension direction of the push rod portion 101 and the cylinder body 200 , and the transverse direction is defined as a direction perpendicular to the axial direction.

[0076] With the above settings, when assembling the barrel 200 and the dose adjustment mechanism 100, the convex portion 201 can be inserted into the interior of the installation groove 102c to achieve the lateral limit connection between the holding portion 102 and the barrel 200; the blocking member 104 abuts against the end wall of the convex portion 201 facing away from the pressing end to axially limit the convex portion 201, thereby achieving the axial limit connection between the holding portion 102 and the barrel 200, so that the holding portion 102 and the barrel 200 are fixed together, ensuring the reliable connection between the barrel 200 and the dose adjustment mechanism 100; this way of setting the connection structure is also beneficial to reducing the installation difficulty between the holding portion 102 and the barrel 200, improving the assembly convenience of the holding portion 102 and the barrel 200, and improving the production efficiency.

[0077] Please refer to Figure 6 and Figure 7 , Figure 7 is Figure 6 a schematic structural view of the holding portion in

[0078] In some embodiments, the connection manner between the blocking member 104 and the holding portion 102 is as follows:

[0079] The end of the holding portion 102 facing away from the pressing end includes two oppositely arranged mounting portions 1023. The opposite end walls of the two mounting portions 1023 form part of the inner wall of the installation groove 102c. The holding portion 102 is further provided with a mounting hole 102d that penetrates the two mounting portions 1023 transversely. The mounting hole 102d communicates with the installation groove 102c, and part of the blocking member 104 is fixedly installed in the mounting hole 102d.

[0080] With the above settings, before assembling the barrel 200 and the dose adjustment mechanism 100, the blocking member 104 and the holding portion 102 are in a separated state. When assembling the barrel 200 and the dose adjustment mechanism 100, first insert the convex portion 201 of the barrel 200 into the interior of the installation groove 102c to achieve the lateral limit connection between the holding portion 102 and the barrel 200; then, insert the blocking member 104 into the mounting hole 102d to achieve the fixed connection between the blocking member 104 and the holding portion 102. The blocking member 104 abuts against the end wall of the convex portion 201 facing away from the pressing end to axially limit the convex portion 201, thereby achieving the axial limit connection between the holding portion 102 and the barrel 200, so that the holding portion 102 and the barrel 200 are fixed together, ensuring the reliable connection between the barrel 200 and the dose adjustment mechanism 100.

[0081] The blocking member 104 is fixedly installed in the mounting hole 102d. Specifically, in some embodiments, the blocking member 104 and the mounting hole 102d can adopt an interference fit manner, which has reliable connection and convenient operation.

[0082] Please refer to Figures 5 - 8 , Figure 8 is Figure 6Schematic structural diagram of the middle blocking member.

[0083] In some other embodiments of the present application, the blocking member 104 includes a blocking member body 1041. The blocking member body 1041 is provided with a notch groove 1041a having an opening at one end, and at least one relief opening 1041b. The blocking member 104 further includes at least one elastic member 1042. The first end of the elastic member 1042 is connected to the inner wall surrounding the relief opening 1041b. In the unloaded state, the second end of the elastic member 1042 extends obliquely away from the pressing end of the push rod portion 101. The length of the elastic member 1042 is not greater than the length between the first end and the second end of the relief opening 1041b, so that the elastic member 1042 can enter the relief opening 1041b after being stressed.

[0084] In the connected state of the dose adjustment mechanism 100 and the barrel 200, both ends of the blocking member 104 are inserted into the mounting holes 102d. The barrel 200 passes through the notch groove 1041a, and the closed end wall surrounding the notch groove 1041a abuts against the outer wall of the barrel 200. The end wall of the second end of the elastic member 1042 abuts against the wall portion surrounding the mounting groove 102c.

[0085] Among them, Figure 6 The direction of the arrow shown is the installation direction of the blocking member 104. The first end of the blocking member 104 that first enters the mounting hole 102d during installation is the first end, and the end that enters the mounting hole 102d last is the second end.

[0086] With the above settings, when installing the blocking member 104, the first end of the blocking member 104 first enters the mounting hole 102d. Under the constraint of the inner wall of the mounting hole 102d, the elastic member 1042 deforms and enters the interior of the relief opening 1041b, and the barrel 200 enters the interior of the notch groove 1041a from the open end of the notch groove 1041a. When the blocking member 104 is installed in place, both ends of the blocking member 104 are inserted into the mounting holes 102d, and the closed end wall surrounding the notch groove 1041a abuts against the outer wall of the barrel 200. Under the limiting action of the barrel 200, the blocking member 104 cannot move further. At the same time, the elastic member 1042 passes through the inner wall of the mounting hole 102d, thereby releasing the constraint of the inner wall of the mounting hole 102d on the elastic member 1042. The elastic member 1042 returns to the unloaded state under the restoring force, that is, the second end of the elastic member 1042 extends obliquely away from the pressing end of the push rod portion 101 and abuts against the wall portion surrounding the mounting groove 102c. Under the limiting action of the wall portion surrounding the mounting groove 102c, the blocking member 104 cannot move in the reverse direction either. In this way, the fixed connection between the blocking member 104 and the holding portion 102 is realized, ensuring the reliable connection between the two, and further ensuring the reliable axial limit of the blocking member 104 on the barrel 200 and the reliable connection between the barrel 200 and the dose adjustment mechanism 100.

[0087] Depend on Figure 6 It can be seen that in the embodiment of the present application, the blocking member 104 includes two elastic members 1042, and the two elastic members 1042 are located on both sides of the width direction of the notch groove 1041a. In this way, the elastic members 1042 on both sides can abut against the wall portion that surrounds the installation groove 102c, so that the blocking member 104 is subjected to balanced force along the width direction of the notch groove 1041a, and the installation of the blocking member 104 is more reliable.

[0088] In some other embodiments, the blocking member 104 may include at least one elastic member 1042. When the blocking member 104 includes one elastic member 1042, the elastic member 1042 may be located at the end of the second end of the notch 1041a, so as to avoid uneven force on the blocking member 104 in the width direction and improve the installation stability of the blocking member 104.

[0089] Of course, the blocking member 104 and the gripping portion 102 are not limited to the above-mentioned connection method. For example, in some other embodiments of the present application, the blocking member 104 includes two limiting protrusions, which are relatively arranged on the wall portion surrounding the mounting groove 102c, and the end wall of the pressing end of the two limiting protrusions facing the push rod portion 101 and the end wall of the pressing end of the protrusion 201 facing away from the push rod portion 101 abut against each other to limit the axial position of the protrusion 201; the end walls of the pressing end of the two limiting protrusions facing away from the push rod portion 101 form an inclined extending guide wall, and the distance between the two guide walls gradually expands in the direction away from the pressing end of the push rod portion 101. When the barrel 200 and the dose adjustment mechanism 100 are assembled, the protrusion 201 can slide along the guide wall. When the protrusion 201 passes over the guide wall, the protrusion 201 is installed in place to achieve a fixed connection between the blocking member 104 and the gripping portion 102.

[0090] Please continue to refer to Figures 6 - 8 In some embodiments of the present application, the portions of the blocking member body 1041 located on both sides of the notch groove 1041a in the width direction are blocking arms 10411, and the mounting portion 1023 close to the first end of the two mounting portions 1023 is the first mounting portion 1023-1, and the mounting portion 1023 close to the second end is the second mounting portion 1023-2;

[0091] The mounting hole 102d includes two first holes 102d-1 arranged in the first mounting portion 1023-1 and a second hole 102d-2 arranged in the second mounting portion 1023-2. The first end of the blocking arm 10411 is inserted into the corresponding first hole 102d-1, and the second end of the blocking member body 1041 is inserted into the second hole 102d-2.

[0092] With the above settings, the blocking member body 1041 of the embodiment of the present application is approximately U-shaped, and the two first holes 102d-1 provided in the first mounting portion 1023-1 and the second hole 102d-2 provided in the second mounting portion 1023-2 can achieve three-point positioning of the blocking member body 1041, making the connection between the blocking member 104 and the holding portion 102 more reliable and making the axial limit of the blocking member 104 on the cylinder body 200 more reliable.

[0093] Please refer to Figures 9 - 11 , Figure 9 For Figure 1 the schematic structural view of the holding portion in the dose adjustment mechanism; Figure 10 For Figure 9 the schematic structural view of the main body portion in Figure 11 For Figure 9 the schematic structural view of the cover plate portion in

[0094] In some embodiments of the present application, the holding portion 102 includes:

[0095] The main body portion 102-1 has a receiving groove 102-1a. One end of the receiving groove 102-1a close to the pressing end of the push rod portion 101 is an open end, and the peripheral wall surrounding the receiving groove 102-1a is provided with the aforementioned one-way card slot 102b;

[0096] The cover plate portion 102-2 is connected to the open end of the main body portion 102-1, and the receiving groove 102-1a forms at least a part of the receiving cavity 102a.

[0097] With the above settings, the holding portion 102 adopts a split structure including the main body portion 102-1 and the cover plate portion 102-2. During the assembly process of the dose adjustment mechanism 100, the ratchet portion 103 can be first installed in the receiving groove 102-1a, and then the cover plate portion 102-2 is connected to the open end of the main body portion 102-1, improving the assembly convenience.

[0098] Among them, the connection method between the cover plate portion 102-2 and the main body portion 102-1 is not limited. For example, the two can be fixed by welding, snap connection, screw connection, etc.

[0099] Such as Figure 9 and Figure 11 As shown in

[0100] Such as Figure 10 and Figure 11As shown, one of the positioning hole e and the positioning post f is provided on the open end wall of the main body part 102-1, and the other of the positioning hole e and the positioning post f is provided on the inner wall of the cover plate part 102-2. During the connection process of the cover plate part 102-2 and the main body part 102-1, the positioning hole e and the positioning post f can play a positioning role, enabling the snap buckle c and the clamping groove d to quickly find the right position for clamping, and improving the operation convenience.

[0101] Please refer to Figure 12 , Figure 12 is Figure 1 a partial cross-sectional view of the dose adjustment mechanism.

[0102] In some embodiments of the present application, the main body part 102-1 includes a first cylinder 102-11 arranged inside the receiving groove 102-1a, and the end wall enclosing the receiving groove 102-1a has a through hole communicating with the first cylinder 102-11. The push rod part 101 passes through the first cylinder 102-11 and is threadedly connected;

[0103] The rattling part 103 includes a second cylinder 1032. The elastic clamping part 1031 is connected to the outer peripheral wall of the second cylinder 1032. One end of the second cylinder 1032 close to the cover plate part 102-2 has a folded part 1032-1 that turns inward. The second cylinder 1032 is movably sleeved on the first cylinder 102-11, and the end wall of the folded part 1032-1 facing away from the cover plate part 102-2 abuts against the opposite end of the first cylinder 102-11.

[0104] As set up by the first cylinder 102-11 above, on the one hand, it can play a positioning role for the second cylinder 1032, improving the installation convenience and positioning accuracy of the rattling part 103; on the other hand, the end wall of the folded part 1032-1 facing away from the cover plate part 102-2 abuts against the opposite end of the first cylinder 102-11, playing an axial limiting role for the rattling part 103. In the state where the push rod part 101 is under a pressing force, the push rod part 101 moves axially, and the opposite end of the first cylinder 102-11 can prevent the axial movement of the rattling part 103, ensuring that the elastic clamping part 1031 and the one-way clamping groove 102b are always in a reliable clamping state, and thus ensuring the normal operation of the dose adjustment mechanism 100 in the embodiments of the present application.

[0105] As Figure 10 shown, in order to reduce the friction force when the rattling part 103 rotates, the end of the first cylinder 102-11 is provided with protrusions 102-12 distributed circumferentially. The end wall of the folded part 1032-1 facing away from the cover plate part 102-2 contacts the protrusions 102-12, reducing the contact area between the folded part 1032-1 and the opposite end of the first cylinder 102-11, reducing the friction force when the rattling part 103 rotates, and making the rattling part 103 rotate more smoothly.

[0106] Among them, the protrusion 102-12 can be a hemispherical structure, further reducing the contact area between the folding portion 1032-1 and the relative end of the first cylinder 102-11, and further reducing the friction when the ratchet portion 103 rotates. In some other embodiments of the present application, the protrusion 102-12 can also be a cylindrical or pointed structure, etc.

[0107] In the embodiment of the present application, the end of the first cylinder 102-11 is provided with protrusions 102-12 distributed circumferentially. In some other embodiments, it is also feasible to provide protrusions on the end wall of the folding portion 1032-1 facing away from the cover plate portion 102-2. The end wall of the folding portion 1032-1 facing away from the cover plate portion 102-2 contacts the end of the first cylinder 102-11 through the protrusions, which can also play a role in reducing the friction when the ratchet portion 103 rotates.

[0108] In addition, since in the dose adjustment mechanism 100 of the embodiment of the present application, the push rod portion 101 can only move unidirectionally under the action of the pressing force and cannot move in the reverse direction, and thus the ratchet portion 103 also has no tendency to move in the reverse direction, there can be a gap between the end wall of the folding portion 1032-1 facing the cover plate portion 102-2 and the cover plate portion 102-2, achieving the technical effect of reducing the friction when the ratchet portion 103 rotates.

[0109] As Figure 10 shown, the end walls enclosing the accommodation groove 102-1a are also provided with a plurality of ribs, and one end of the rib is connected to the first cylinder 102-11. In this way, the rib can play a role in strengthening the structure of the first cylinder 102-11 and improving the structural stability of the first cylinder 102-11.

[0110] Please refer to Figure 13 Figure 13 For Figure 1 the structural schematic diagram of the push rod portion and the pressing portion in the dose adjustment mechanism.

[0111] In order to enable the push rod portion 101 to move axially and rotate when under the pressing force, in some embodiments of the present application, the push rod portion 101 has a pressing end, and the dose adjustment mechanism 100 further includes a pressing portion 105, and the pressing portion 105 is rotatably connected to the pressing end of the push rod portion 101.

[0112] In this way, the operator can apply a pressing force to the push rod portion 101 by pressing the pressing portion 105 as above. The cross-sectional area of the pressing portion 105 can be set to be larger than the cross-sectional area of the push rod portion 101, which is convenient for the operator to apply force and improves the operation convenience; the pressing portion 105 is rotatably connected to the pressing end of the push rod portion 101, so that the push rod portion 101 can rotate unobstructed when under the pressing force, ensuring that the dose adjustment mechanism 100 of the present application can work properly. ​

[0113] Among them, the connection manner between the pressing part 105 and the push rod part 101 is not limited. For example, in some embodiments of the present application, the push rod part 101 includes a screw part, a connecting rod part and a spherical connecting part. The connecting rod part is connected between the screw part and the spherical connecting part. The pressing part 105 has a spherical connecting groove. The spherical connecting part is installed inside the spherical connecting groove. The spherical connecting part can rotate inside the spherical connecting groove to realize the rotational connection between the pressing part 105 and the push rod part 101. And the diameter of the open end of the spherical connecting groove is smaller than the diameter of the spherical connecting part. Therefore, the spherical connecting part can be reliably installed inside the spherical connecting groove without coming out, ensuring the reliable axial connection between the pressing part 105 and the push rod part 101.

[0114] The embodiment of the present application further provides an injection device, including:

[0115] A cylinder 200 having an injection end and an open end;

[0116] A sealing plug 300 slidably arranged inside the cylinder 200. Taking the sealing plug 300 as a boundary, the area inside the cylinder 200 close to the injection end forms a storage cavity 200a for storing an injection substance.

[0117] The dose adjustment mechanism 100 of the aforementioned injection device. The holding part 102 of the dose adjustment mechanism 100 is connected to the open end of the cylinder 200, and the push rod part 101 of the dose adjustment mechanism 100 is connected to the sealing plug 300.

[0118] The injection device of the embodiment of the present application includes the aforementioned dose adjustment mechanism 100, and thus has the same technical effects as the aforementioned dose adjustment mechanism 100, which will not be elaborated herein.

[0119] Among them, the connection manner between the push rod part 101 and the sealing plug 300 is not limited. For example, the push rod part 101 and the sealing plug 300 can be connected by interference fit. Specifically, the end wall of the sealing plug 300 facing the open end has a connecting groove, and the outer diameter of the connecting end of the push rod part 101 is greater than the inner diameter of the connecting groove, and at least part of the connecting end of the push rod part 101 is inserted into the connecting groove.

[0120] The above is only the preferred embodiment of the present application. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A dose adjustment mechanism for an injection device, characterized in that, It includes a push rod part, a holding part and a ratchet part. The push rod part passes through the holding part and is threadedly connected. The ratchet part is sleeved on the push rod part and is circumferentially limited and connected. The push rod part can move axially relative to the ratchet part. The holding part has a receiving cavity, and the circumferential wall enclosing the receiving cavity is provided with one-way card slots distributed circumferentially. The ratchet part is located in the receiving cavity. The ratchet part has an elastic clamping part, and the elastic clamping part is snapped into any one of the one-way card slots. In a state where the push rod part is subjected to a pressing force, the push rod part can move axially and drive the ratchet part to rotate synchronously under the action of the thread, so that the elastic clamping part slides along the circumferential wall enclosing the receiving cavity to be snapped into one of the one-way card slots at the front end.

2. The dose adjustment mechanism according to claim 1, characterized in that The circumferential wall enclosing the receiving cavity is provided with a plurality of ratchet teeth distributed circumferentially. An arcuate groove is formed between adjacent ratchet teeth, and the arcuate groove is the one-way card slot.

3. The dose adjustment mechanism according to claim 1, characterized in that, A limiting groove is provided on the outer peripheral wall of the push rod part, and the limiting groove extends along the axial direction of the push rod part. The ratchet part is provided with a limiting protrusion, and at least part of the limiting protrusion is slidably inserted into the corresponding limiting groove.

4. The dose adjustment mechanism according to any one of claims 1-3, characterized in that, The push rod part has a pressing end, and an installation groove is provided on the end wall of the holding part facing away from the pressing end. The installation groove is used for laterally limiting and installing a protruding part located at the opening end of the barrel of the injection device. The dose adjustment mechanism further includes a blocking member, and the blocking member is connected to the holding part. The blocking member is configured to abut against the end wall of the protruding part facing away from the pressing end to axially limit the protruding part.

5. The dose adjustment mechanism according to claim 4, characterized in that, The end of the holding part facing away from the pressing end includes two oppositely arranged installation parts. The opposite end walls of the two installation parts form part of the inner wall of the installation groove. The holding part is further provided with an installation hole penetrating through the two installation parts laterally. The installation hole is communicated with the installation groove, and part of the blocking member is fixedly installed in the installation hole.

6. The dose adjustment mechanism according to claim 5, characterized in that, The blocking member includes a blocking member body. The blocking member body is provided with a notch groove with an opening at the first end and at least one avoidance opening. The blocking member further includes at least one elastic member. The first end of the elastic member is connected to the inner wall enclosing the avoidance opening. In an unloaded state, the second end of the elastic member extends obliquely in a direction away from the pressing end, and the length of the elastic member is not greater than the length between the first end and the second end of the avoidance opening. In a state where the dose adjustment mechanism is connected to the barrel, both ends of the blocking member are inserted into the installation hole, the barrel passes through the notch groove, the closing end wall enclosing the notch groove abuts against the outer wall of the barrel, and the end wall of the second end of the elastic member abuts against the wall part enclosing the installation groove.

7. The dose adjustment mechanism according to claim 6, characterized in that, The portions of the blocking member body on both sides in the width direction of the notch groove are blocking arms. Among the two mounting portions, the mounting portion closer to the first end is the first mounting portion, and the mounting portion closer to the second end is the second mounting portion. The mounting holes include two first holes provided in the first mounting portion and a second hole provided in the second mounting portion. The first end of the blocking arm is inserted into the corresponding first hole, and the second end of the blocking member body is inserted into the second hole.

8. The dose adjustment mechanism according to any one of claims 1-3, characterized in that, The holding portion includes: A body portion having a receiving groove. One end of the receiving groove close to the pressing end of the push rod portion is an open end, and a one-way card slot is provided on the peripheral wall surrounding the receiving groove. A cover plate portion connected to the open end of the body portion, and the receiving groove forms at least part of the receiving cavity.

9. The dose adjustment mechanism according to claim 8, characterized in that, The body portion includes a first cylinder provided inside the receiving groove. The end wall surrounding the receiving groove has a through hole communicating with the first cylinder, and the push rod portion passes through the first cylinder and is threadedly connected. The sound generating tooth portion includes a second cylinder. The elastic clamping portion is connected to the outer peripheral wall of the second cylinder. One end of the second cylinder close to the cover plate portion has a folded portion that folds inward. The second cylinder is movably sleeved on the first cylinder, and the end wall of the folded portion facing away from the cover plate portion abuts against the opposite end portion of the first cylinder.

10. The dose adjustment mechanism according to any one of claims 1-3, characterized in that, The push rod portion has a pressing end, and the dose adjustment mechanism further includes a pressing portion rotatably connected to the pressing end.

11. An injection device, characterized in that, It includes: A cylinder having a dispensing end and an open end; A sealing plug slidably provided inside the cylinder. Taking the sealing plug as a boundary, the area inside the cylinder close to the dispensing end forms a storage cavity for storing the injection substance. The dose adjustment mechanism of the injection device according to any one of claims 1-10, wherein the holding portion of the dose adjustment mechanism is connected to the open end of the cylinder, and the push rod portion of the dose adjustment mechanism is connected to the sealing plug.

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