Dose setting mechanism for an injection device and injection device

Abstract

The application relates to the technical field of medical devices, in particular to a dose adjusting mechanism of an injection device and the injection device. A push rod part penetrates a holding part and is threadedly connected, a click part is sleeved with the push rod part and is connected in a circumferential limiting mode, the push rod part is movable along an axial direction relative to the click part, the holding part has a containing cavity, a circumferential wall surrounding the containing cavity is provided with one-way clamping grooves distributed in a circumferential direction, the click part is located in the containing cavity, the click part has an elastic clamping part, and the elastic clamping part is clamped into any one-way clamping groove; under the state that the push rod part is pressed, the push rod part can move along the axial direction and drive the click part to synchronously rotate under the action of the thread, so that the elastic clamping part slides along the circumferential wall surrounding the containing cavity to be clamped into one of the one-way clamping grooves at the front end. The application converts the axial control of the push rod part into the rotation control of the click part, and discretizes the rotation movement of the click part into fixed-angle grading, the single grading axial displacement 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, in particular to a dose adjusting mechanism of an injection device and the injection device. BACKGROUND

[0002] The related art injection device comprises a sleeve component, a push rod component and a clamping 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 sleeve component and moves along the axial direction of the sleeve component. The concave-convex structure is blocked by the clamping component during the movement of the push rod component. The clamping component is arranged at the opening of the first end of the push rod component sleeved with the sleeve component and is adapted to cooperate with the concave-convex structure on the push rod component during the movement of the push rod component along the axial direction of the sleeve component to block the movement of the push rod component. The distance between adjacent concave-convex structures has a corresponding relationship with the dose of the injection. Through the cooperation of the concave-convex structure and the clamping component, the movement of the push rod component is blocked, so that the dose of the injection can be accurately controlled and the accuracy of the injection amount of the injection can be improved.

[0003] In the related art injection device, the distance between adjacent concave-convex structures determines the minimum dose unit. If a smaller dose is to be achieved, the distance between adjacent concave-convex structures needs to be shortened. However, due to the limitation of machining precision such as mechanical machining capability, too small distance may cause the concave-convex structure to be unable to be stably formed or be easily worn, resulting in that the related art injection device is only suitable for large dose injection and cannot meet the demand of small dose injection. SUMMARY

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

[0005] To solve the above technical problems, the present application provides a dose adjusting mechanism of an injection device, which comprises a push rod part, a holding part and a responding tooth part. The push rod part passes through the holding part and is threadedly connected. The responding tooth part is sleeved with the push rod part and is connected in circumferential limiting mode. The push rod part can move along the axial direction relative to the responding tooth part. The holding part has a containing cavity. The circumferential wall surrounding the containing cavity is provided with unidirectional clamping grooves distributed in the circumferential direction. The responding tooth part is located in the containing cavity. The responding tooth part has an elastic clamping part. The elastic clamping part is clamped into any unidirectional clamping groove.

[0006] Under the state that the push rod part is pressed, the push rod part can move along the axial direction and drive the responding tooth part to rotate synchronously under the action of the thread, so that the elastic clamping part slides along the circumferential wall surrounding the containing cavity to be clamped into one of the unidirectional clamping grooves at the front end.

[0007] Optionally, the circumferential wall surrounding the containing cavity is provided with a plurality of ratchet teeth distributed in the circumferential direction. Ratchet grooves are formed between adjacent ratchet teeth. The ratchet grooves are the unidirectional clamping grooves.

[0008] Optionally, the outer peripheral wall of the push rod portion is provided with a limiting groove, the limiting groove extends along the axial direction of the push rod portion, the ring tooth portion is provided with a limiting protrusion, and at least 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 end wall of the grip portion facing away from the pressing end is provided with a mounting groove, the mounting groove being used for mounting a raised portion located at the open end of the barrel of the injection device in a transverse limited manner;

[0010] The dose adjustment mechanism further includes a blocking member connected to the grip portion, and the blocking member is configured to abut against an end wall of the protrusion facing away from the pressing end to limit the axial position of the protrusion.

[0011] Optionally, the end of the holding portion facing away from the pressing end includes two oppositely arranged mounting portions, and the opposite end walls of the two mounting portions form part of the inner wall of the mounting groove. The holding portion is also provided with a mounting hole that passes through the two mounting portions in the transverse direction, and the mounting hole is connected to 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 with a first end open, 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, and in a non-stressed 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 no greater than the length between the first end of the avoidance opening and the second end of the avoidance opening;

[0013] When the dose adjustment mechanism and the barrel are in a connected state, both ends of the blocking member are inserted into the mounting holes, 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 located on both sides of the notch in the width direction are blocking arms, and of 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 holes include two first holes provided on the first mounting portion and a second hole provided on 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 gripping portion includes:

[0017] A main body portion, wherein the main body portion has a receiving groove, an end of the receiving groove close to the pressing end of the push rod portion is an open end, and a peripheral wall surrounding the receiving groove is provided with the one-way clamping groove;

[0018] A cover portion is connected to the open end of the main body portion, and the accommodating groove forms at least a portion of the accommodating cavity.

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

[0020] The ringing tooth portion includes a second cylinder, the elastic clamping portion is connected to the outer peripheral wall of the second cylinder, and the second cylinder has an inwardly folded portion at one end close to the cover portion. The second cylinder is movably fitted onto the first cylinder, and the folded portion faces away from the end wall of the cover portion and abuts against the opposite end of the first cylinder.

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

[0022] The present application also provides an injection device, characterized by comprising:

[0023] a barrel having a discharge end and an open end;

[0024] A sealing plug is slidably disposed inside the barrel, with the sealing plug as the boundary, and an area inside the barrel near the discharge end forms a storage cavity, wherein the storage cavity is used to store the injection;

[0025] The dose adjustment mechanism of the aforementioned injection device has a gripping portion connected to the open end of the barrel, and a push rod portion connected to the sealing plug.

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

[0027] The dose adjustment mechanism of the present application converts the axial displacement control of the push rod part into the rotational motion control of the snap tooth part through the precise threaded cooperation between the push rod part and the grip part, and the circumferential limit connection between the push rod part and the snap tooth part. At the same time, the rotational motion of the snap tooth part is discretized into fixed angle steps through the clamping cooperation of the one-way slots and the elastic clamping part distributed along the circumference. By matching the thread pitch with the number of one-way slots, the single-step axial displacement of the push rod part is extremely small, meeting the needs of small-dose injection. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic structural diagram of a specific embodiment of the dosage adjustment mechanism provided in this application;

[0029] Figure 2 for Figure 1 Schematic diagram of the structure of the dose adjustment mechanism without the cover plate;

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

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

[0032] Figure 5 for Figure 3 A schematic diagram of the structure of the gripping portion, blocking member and barrel in the injection device;

[0033] Figure 6 for Figure 5 A schematic diagram of the structure of the middle grip portion and the blocking member;

[0034] Figure 7 for Figure 6 A schematic diagram of the structure of the middle grip portion;

[0035] Figure 8 for Figure 6 A schematic structural diagram of the middle blocking member;

[0036] Figure 9 for Figure 1 A schematic diagram of the structure of the grip portion of the dose adjustment mechanism;

[0037] Figure 10 for Figure 9 Schematic diagram of the structure of the main body;

[0038] Figure 11 for Figure 9 Schematic diagram of the structure of the middle cover plate;

[0039] Figure 12 for Figure 1 a partial cross-sectional view of the dose adjustment mechanism;

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

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

[0042] 100-dose adjustment mechanism;

[0043] 101- push rod part;

[0044] 102-handle; 102-1-body; 102-1a-accommodating slot; 102-11-first cylinder; 102-12-protrusion; 102-2-cover; 102a-accommodating cavity; 102b-one-way slot; 102c-mounting slot; 102d-mounting hole; 102d-1-first hole; 102d-2-second hole; 1021-ratchet; 1022-ratchet slot; 1023-mounting portion; 1023-1-first mounting portion; 1023-2-second mounting portion;

[0045] 103-ringing tooth portion; 1031-elastic clamping portion; 1032-second cylinder; 1032-1-folding portion;

[0046] 104-blocking member; 1041-blocking member body; 1041a-notch groove; 1041b-avoidance opening; 10411-blocking arm; 1042-elastic member;

[0047] 105-pressing part;

[0048] a-limiting groove; b-limiting protrusion; c-buckle; d-clamping groove; e-positioning hole; f-positioning column;

[0049] 200-cylinder; 201-protrusion; 200a-storage chamber;

[0050] 300-Sealing plug. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0052] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0053] It should be understood that references throughout this specification to "some embodiments" mean that a particular feature, structure, or characteristic associated with an embodiment is included in at least one embodiment of the present application. Therefore, the appearance of "in some embodiments" throughout this specification does not necessarily refer to the same embodiment. Furthermore, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0054] In the description herein, unless otherwise expressly specified or limited, the terms "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this disclosure in specific contexts.

[0055] Please refer to Figure 1-Figure 3 , Figure 1 This is a schematic structural diagram of a specific embodiment of the dosage adjustment mechanism provided in this application; Figure 2 for Figure 1 Schematic diagram of the structure of the dose adjustment mechanism without the cover plate; Figure 3 This is an axial cross-sectional view of a specific embodiment of the injection device provided by the present application.

[0056] The present embodiment provides a dose adjustment mechanism 100 for an injection device, comprising a push rod 101, a grip 102, and a snapping tooth 103. The push rod 101 passes through the grip 102 and is threadedly connected thereto. The snapping tooth 103 is fitted over the push rod 101 and circumferentially limited thereto. The push rod 101 is axially movable relative to the snapping tooth 103. The grip 102 has an accommodating cavity 102a. The circumferentially distributed one-way slots 102b are provided on a peripheral wall of the accommodating cavity 102a. The snapping tooth 103 is located in the accommodating cavity 102a and has an elastic snapping portion 1031 that snaps into any one of the one-way slots 102b.

[0057] When the push rod part 101 is subjected to pressing force, the push rod part 101 can move axially and drive the tooth part 103 to rotate synchronously under the action of the thread, so that the elastic clamping part 1031 slides along the peripheral wall of the accommodating cavity 102a to be clamped into one of the one-way clamping grooves 102b at the front end.

[0058] Figure 2 The arrow direction is the rotation direction of the ringing tooth portion 103, that is, the sliding direction of the elastic clamping portion 1031 along the peripheral wall surrounding the accommodating cavity 102a. The front end here refers to the end to which the sliding direction of the elastic clamping portion 1031 points. 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 arranged inside the barrel 200. The area inside the barrel 200 near the injection end is bounded by the sealing plug 300 to form a storage chamber 200a. The storage chamber 200a is used to store the injection. When the dose adjustment mechanism 100 of the embodiment of the present application is applied to the injection device, the gripping portion 102 is connected to the open end of the barrel 200. The gripping portion 102 can be gripped by the operator so that the gripping portion 102 and the barrel 200 are in a fixed state. The push rod portion 101 passes through the gripping portion 102 and is connected to the sealing plug 300. The push rod portion 101 and the gripping portion 102 are threadedly connected. When the gripping portion 102 is operated When the operator holds the push rod 101 and the push rod 101 is subjected to pressing force, the push rod 101 can move axially and rotate under the action of the thread; the snap tooth portion 103 is fitted onto the push rod 101 and is circumferentially limited and connected, and the push rod 101 can move axially relative to the snap tooth portion 103, and the gripping portion 102 has a receiving cavity 102a, and the snap tooth portion 103 is located in the receiving cavity 102a, that is, the snap tooth portion 103 can rotate synchronously with the rotation of the push rod 101, and the snap tooth portion 103 will not hinder the axial movement of the push rod 101; when the thread pitch of the push rod 101 and the gripping portion 102 are fixed, the rotation angle of the snap tooth portion 103 (push rod 101) strictly corresponds to the axial displacement of the push rod 101, such as the push rod 101 and the gripping portion. The thread pitch of 102 is 1mm. When the tooth portion 103 (push rod portion 101) rotates 360°, the push rod portion 101 moves 1mm in the axial direction, thereby ensuring that the dosage is controllable; the peripheral wall surrounding the accommodating chamber 102a is provided with a circumferentially distributed one-way card groove 102b, and the tooth portion 103 has an elastic card connection portion 1031, which is snapped into any one-way card groove 102b; in this way, the circumferentially distributed one-way card groove 102b discretizes the circumferential motion of the tooth portion 103, and when the push rod portion 101 is subjected to pressing force, the push rod portion 101 moves in the axial direction and drives the tooth portion 103 to rotate synchronously under the action of the thread, and the elastic card connection portion 1031 gradually slides out of the current one-way card groove along the peripheral wall surrounding the accommodating chamber 102a. The push rod 101 moves a fixed distance each time the elastic engaging portion 1031 slides over a one-way slot 102b. Thus, each one-way slot 102b corresponds to a gear position. By designing the number of one-way slots 102b, each one-way slot 102b can correspond to a specific dosage unit. For example, the thread pitch of the push rod 101 and the gripping portion 102 is 1mm, and the peripheral wall surrounding the accommodating cavity 102a is provided with 12 one-way slots 102b, with adjacent one-way slots 102b spaced 30° apart. Each time the snap-tooth portion 103 slides over a one-way slot 102b, the push rod 101 moves a distance equal to the ratio of the thread pitch to the number of one-way slots, i.e., approximately 0.0833mm, breaking through the single minimum injection limit of the traditional axial convex-concave structure, meeting the small dose injection requirement.

[0059] In the process of gradually sliding out of the current one-way clamping groove 102b, the elastic clamping part 1031 is extruded and deformed, and the elastic clamping part 1031 gradually accumulates energy; when the elastic clamping part 1031 passes the current one-way clamping groove 102b, the elastic potential energy of the elastic clamping part 1031 is released, and the elastic clamping part 1031 is instantly snapped into the next one-way clamping groove 102b. The impact of the elastic clamping part 1031 and the wall surrounding the accommodating cavity 102a will produce a "click" sound, or cause a slight vibration of the push rod part 101. When the user hears the "click" sound or feels the vibration, it indicates that one dose unit of injection is completed. The user can accurately control the total injection amount by counting the number of "click" sounds or vibrations, thereby avoiding injection errors as much as possible.

[0060] The aforementioned one-way clamping groove 102b refers to that under the state that the push rod part 101 is pressed, the elastic clamping part 1031 can only slide along the wall surrounding the accommodating cavity 102a in one direction to be clamped into the one-way clamping groove 102b at the front end, and cannot slide in the reverse direction. That is to say, it is ensured that the click part 103 can only rotate in one direction, and cannot rotate in the reverse direction, thereby ensuring that the push rod part 101 and the sealing plug 300 can only move in one direction under the action of the pressing force, and cannot move in the reverse direction. On the one hand, the accuracy of the injection amount is improved, and injection errors are avoided as much as possible. On the other hand, the secondary use of the dose adjusting mechanism 100 is avoided, the anti-reuse requirement of disposable medical devices is met, the risk of cross infection is reduced, and the safety is improved.

[0061] In summary, the dose adjusting mechanism 100 of the embodiment of the present application converts the axial displacement control of the push rod part 101 into the rotational motion control of the click part 103 through the precise thread cooperation of the push rod part 101 and the holding part 102, and the circumferential limiting connection of the push rod part 101 and the click part 103. At the same time, the rotational motion of the click part 103 is discretized into fixed-angle divisions through the clamping cooperation of the one-way clamping grooves 102b and the elastic clamping parts 1031. By matching the thread pitch and the number of one-way clamping grooves, the single division axial displacement of the push rod part 101 is extremely small, meeting the small dose injection requirement.

[0062] As shown in FIG. 1, Figure 2 In some embodiments of the present application, the wall surrounding the accommodating cavity 102a is provided with a plurality of ratchets 1021 distributed in the circumferential direction, and a ratchet groove 1022 is formed between adjacent ratchets 1021. The ratchet groove 1022 is the aforementioned one-way clamping groove 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. When the push rod part 101 is subjected to pressing pressure, the elastic clamping part 1031 can slide along the inclined surface, thereby smoothly sliding over the top of the current ratchet 1021 and falling into the next ratchet groove 1022. The inclined surface can reduce the resistance of the forward operation and improve the convenience of operation; when the elastic clamping part 1031 slides over the top of the current ratchet 1021 and falls into the next ratchet groove 1022, a clear "click" sound and / or an operating feel (such as a slight vibration) is usually generated, giving the user clear feedback that the unit metered injection is completed; and during the reverse operation, the blocking surface of the ratchet 1021 will block the elastic clamping part 1031, ensuring that the push rod part 101 and the sealing plug 300 cannot move in the opposite direction, avoiding injection errors as much as possible, and preventing the dose adjustment mechanism 100 from being reused, thereby improving safety. Moreover, the shape of the ratchet 1021 is relatively standard, and is easy to manufacture by machining, stamping, casting or injection molding, thereby improving molding convenience and reducing production costs.

[0064] Please refer to Figure 2 and Figure 4 , Figure 4 for Figure 1 Schematic diagram of the structure of the tooth part in the dose adjustment mechanism.

[0065] In the embodiment of the present application, the rattle portion 103 has two elastic engaging portions 1031 spaced circumferentially. The two elastic engaging portions 1031 cooperate with the ratchet 1021 to achieve one-way locking, which helps distribute the load, improves the load-bearing capacity of the dose adjustment mechanism 100 of the embodiment of the present application, and enhances the locking accuracy of the push rod portion 101 and the sealing plug 300. In other embodiments of the present application, the rattle portion 103 has at least one elastic engaging portion 1031.

[0066] The elastic clamping portion 1031 is made of a material capable of generating elastic deformation, such as plastic with a certain elasticity.

[0067] As mentioned above, the push rod portion 101 and the ring tooth portion 103 are connected along the circumferential limit direction, and the push rod portion 101 can move axially relative to the ring tooth portion 103. Specifically in this embodiment, Figure 2 As shown, the outer peripheral wall of the push rod portion 101 is provided with a limiting groove a, which extends along the axial direction of the push rod portion 101, and the ring tooth portion 103 is provided with a limiting protrusion b, at least part of which 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 be transitionally matched. On the one hand, the limiting groove a can reliably limit the limiting protrusion b along the width direction, and avoid the 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 provided on the push rod portion 101, and the limiting protrusion b is provided on the tooth portion 103, which can also avoid interference with the threaded fit between the push rod portion 101 and the grip portion 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 rattling tooth portion 103 includes two oppositely arranged limiting protrusions b; correspondingly, the push rod portion 101 includes two back-to-back 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 rattling 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 Figure 5-Figure 6 , Figure 5 for Figure 3 A schematic diagram of the structure of the gripping portion, blocking member and barrel in the injection device; Figure 6 for Figure 5 Schematic diagram of the structure of the grip and 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, which 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 connected to the grip portion 102 . The blocking member 104 is configured to abut against an end wall of the protrusion 201 facing away from the pressing end to limit the axial position of the protrusion 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] As configured above, when assembling the barrel 200 and the dose adjustment mechanism 100, the protrusion 201 can be inserted into the interior of the mounting groove 102c to achieve a lateral limit connection between the grip portion 102 and the barrel 200; the blocking member 104 abuts against the end wall of the protrusion 201 facing away from the pressing end to axially limit the protrusion 201, thereby achieving an axial limit connection between the grip portion 102 and the barrel 200, thereby fixing the grip portion 102 and the barrel 200 as one, and ensuring a reliable connection between the barrel 200 and the dose adjustment mechanism 100; this connection structure arrangement is also conducive to reducing the difficulty of installing the grip portion 102 and the barrel 200, improving the assembly convenience of the grip portion 102 and the barrel 200, and improving production efficiency.

[0077] Please refer to Figure 6 and Figure 7 , Figure 7 for Figure 6 Schematic diagram of the structure of the middle grip.

[0078] In some embodiments, the blocking member 104 and the grip portion 102 are connected in the following manner:

[0079] The end of the holding portion 102 facing away from the pressing end includes two oppositely arranged mounting portions 1023, and the opposite end walls of the two mounting portions 1023 form part of the inner wall of the mounting groove 102c. The holding portion 102 is also provided with a mounting hole 102d that passes through the two mounting portions 1023 in the transverse direction. The mounting hole 102d is connected to the mounting groove 102c, and a part of the blocking member 104 is fixedly installed in the mounting hole 102d.

[0080] As configured above, before assembling the barrel 200 and the dose adjustment mechanism 100, the blocking member 104 and the gripping portion 102 are in a separated state. When assembling the barrel 200 and the dose adjustment mechanism 100, the raised portion 201 of the barrel 200 is first inserted into the interior of the mounting groove 102c to achieve a lateral limit connection between the gripping portion 102 and the barrel 200; then, the blocking member 104 is inserted into the mounting hole 102d to achieve a fixed connection between the blocking member 104 and the gripping portion 102. The blocking member 104 and the end wall of the raised portion 201 facing away from the pressing end abut against each other to axially limit the raised portion 201, thereby achieving an axial limit connection between the gripping portion 102 and the barrel 200, thereby fixing the gripping portion 102 and the barrel 200 as one, and ensuring a reliable connection between the barrel 200 and the dose adjustment mechanism 100.

[0081] The blocking member 104 is fixedly mounted in the mounting hole 102d. Specifically, in some embodiments, the blocking member 104 and the mounting hole 102d can be interference-fitted, which ensures reliable connection and convenient operation.

[0082] Please refer to Figure 5-Figure 8 , Figure 8 for Figure 6Schematic diagram of the structure of the blocking member.

[0083] In some other embodiments of the present application, the blocking member 104 includes a blocking member body 1041, which is provided with a notch groove 1041a with an opening at a first end, and at least one avoidance opening 1041b. The blocking member 104 also includes at least one elastic member 1042, wherein a first end of the elastic member 1042 is connected to an inner wall surrounding the avoidance opening 1041b, and in an unstressed state, a second end of the elastic member 1042 extends obliquely in a direction away from the pressing end of the push rod portion 101, and a length of the elastic member 1042 is no greater than a length between the first end and the second end of the avoidance opening 1041b, so that the elastic member 1042 can enter the avoidance opening 1041b after being subjected to force;

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

[0085] in, Figure 6 The direction of the arrow is the installation direction of the blocking member 104. When installing, the end of the blocking member 104 that first enters the installation hole 102d is the first end, and the end that last enters the installation hole 102d is the second end.

[0086] As described above, when the blocking member 104 is installed, the first end of the blocking member 104 first enters the installation hole 102d. Under the constraint of the inner wall of the installation hole 102d, the elastic member 1042 is deformed and enters the inside of the avoidance opening 1041b, and the cylinder 200 enters the inside of the notch groove 1041a from the open end of the notch groove 1041a; when the blocking member 104 is installed in place, the two ends of the blocking member 104 are inserted into the installation hole 102d, and the closed end wall of the notch groove 1041a abuts against the outer wall of the cylinder 200. Under the limiting action of the cylinder 200, the blocking member 104 cannot move further; at the same time, the elastic member 1042 is retracted from the installation hole 102 d penetrates, thereby releasing the constraint of the inner wall of the mounting hole 102d on the elastic member 1042, and the elastic member 1042 returns to the unstressed state under the action of the restoring force, that is, the second end of the elastic member 1042 extends obliquely in the direction away from the pressing end of the push rod portion 101, and abuts against the wall portion that forms the mounting groove 102c. Under the limiting action of the wall portion that forms the mounting groove 102c, the blocking member 104 cannot move in the reverse direction, thereby achieving a fixed connection between the blocking member 104 and the gripping portion 102, ensuring a reliable connection between the two, and further ensuring a reliable axial limitation of the barrel 200 by the blocking member 104, and ensuring a 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 to minimize 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 two limiting protrusions facing the pressing end of the push rod portion 101 abuts against the end wall of the protrusion 201 facing away from the pressing end of the push rod portion 101 to limit the axial position of the protrusion 201; the end walls of the two limiting protrusions facing away from the pressing end of 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 Figure 6-Figure 8 In some embodiments of the present application, the portions of the blocking member body 1041 located on both sides of the notch 1041a in the width direction are blocking arms 10411, and the mounting portion 1023 closer to the first end of the two mounting portions 1023 is a first mounting portion 1023-1, and the mounting portion 1023 closer to the second end is a second mounting portion 1023-2.

[0091] The mounting hole 102d includes two first holes 102d-1 set in the first mounting part 1023-1, and a second hole 102d-2 set in the second mounting part 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] As configured above, the blocking member body 1041 of the embodiment of the present application is approximately a U-shaped structure. The two first holes 102d-1 provided on the first mounting portion 1023-1 and the second hole 102d-2 provided on the second mounting portion 1023-2 can realize three-point positioning of the blocking member body 1041, so that the connection between the blocking member 104 and the holding portion 102 is more reliable, and the axial limitation of the cylinder 200 by the blocking member 104 is more reliable.

[0093] Please refer to Figures 9-11 , Figure 9 for Figure 1 A schematic diagram of the structure of the grip portion of the dose adjustment mechanism; Figure 10 for Figure 9 Schematic diagram of the structure of the main body; Figure 11 for Figure 9 Schematic diagram of the structure of the middle cover.

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

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

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

[0097] As configured above, the grip portion 102 adopts a split structure including a main body portion 102-1 and a cover portion 102-2. During the assembly process of the dose adjustment mechanism 100, the snap tooth portion 103 can be first installed in the accommodating groove 102-1a, and then the cover portion 102-2 can be connected to the open end of the main body portion 102-1, thereby improving assembly convenience.

[0098] There is no limitation on the connection method between the cover portion 102 - 2 and the main body portion 102 - 1 . For example, the two can be fixed by welding, clamping, or threaded connection.

[0099] like Figure 9 and Figure 11 As shown, in some embodiments of the present application, one of the cover portion 102-2 and the main body portion 102-1 is provided with a snap c, and the other is provided with a snap groove d, and the cover portion 102-2 and the main body portion 102-1 are fixed by snapping together the snap c and the snap groove d.

[0100] like Figure 10 and Figure 11As shown, the open end wall of the main body 102-1 is provided with one of the positioning hole e and the positioning column f, and the inner wall of the cover portion 102-2 is provided with the other of the positioning hole e and the positioning column f. During the connection process between the cover portion 102-2 and the main body 102-1, the positioning hole e and the positioning column f can play a positioning role, so that the buckle c and the snap-in groove d can be quickly found and snapped in, thereby improving the convenience of operation.

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

[0102] In some embodiments of the present application, the main body 102-1 includes a first barrel 102-11 disposed within the receiving groove 102-1a. The end wall surrounding the receiving groove 102-1a has a through hole communicating with the first barrel 102-11. The push rod 101 passes through the first barrel 102-11 and is threadedly connected.

[0103] The ringing tooth portion 103 includes a second cylinder 1032, an elastic clamping portion 1031 is connected to the outer peripheral wall of the second cylinder 1032, and the end of the second cylinder 1032 close to the cover portion 102-2 has an inwardly folded folding portion 1032-1, the second cylinder 1032 is movably fitted onto the first cylinder 102-11, and the folding portion 1032-1 faces away from the end wall of the cover portion 102-2 and contacts the opposite end of the first cylinder 102-11.

[0104] As described above, the setting of the first cylinder 102-11 can, on the one hand, play a role in positioning the second cylinder 1032, thereby improving the installation convenience and positioning accuracy of the ringing tooth portion 103; on the other hand, the end wall of the folding portion 1032-1 facing away from the cover portion 102-2 and the opposite end of the first cylinder 102-11 abut against each other, thereby playing a role in axially limiting the ringing tooth portion 103. When the push rod portion 101 is subjected to pressing force, the push rod portion 101 moves axially, and the opposite end of the first cylinder 102-11 can prevent the axial movement of the ringing tooth portion 103, thereby ensuring that the elastic clamping portion 1031 and the one-way clamping slot 102b are always in a reliable clamping state, thereby ensuring the normal operation of the dose adjustment mechanism 100 of the embodiment of the present application.

[0105] like Figure 10 As shown, in order to reduce the friction force when the rattling tooth portion 103 rotates, the end of the first cylinder 102-11 is provided with a protrusion 102-12 distributed along the circumferential direction, and the end wall of the folding portion 1032-1 facing away from the cover portion 102-2 contacts the protrusion 102-12, thereby reducing the contact area between the folding portion 1032-1 and the opposite end of the first cylinder 102-11, reducing the friction force when the rattling tooth portion 103 rotates, and making the rattling tooth portion 103 rotate more smoothly.

[0106] The protrusion 102-12 may be a hemispherical structure, further reducing the contact area between the folded portion 1032-1 and the opposite end of the first cylinder 102-11, and further reducing the friction when the rattling tooth portion 103 rotates. In other embodiments of the present application, the protrusion 102-12 may also be a columnar, pointed, or angular structure.

[0107] In the embodiment of the present application, the end of the first cylinder 102-11 is provided with protrusions 102-12 distributed along the circumferential direction. In other embodiments, it is also feasible to provide protrusions on the end wall of the folding portion 1032-1 facing away from the cover portion 102-2. The end wall of the folding portion 1032-1 facing away from the cover portion 102-2 contacts the end of the first cylinder 102-11 through the protrusions, which can also reduce the friction force when the rattle 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 in one direction under the action of pressing force and cannot move in the opposite direction, and thus the snapping tooth portion 103 has no tendency to move in the opposite direction, there can be a gap between the end wall of the folding portion 1032-1 facing the cover portion 102-2 and the cover portion 102-2, thereby achieving the technical effect of reducing the friction force when the snapping tooth portion 103 rotates.

[0109] like Figure 10 As shown, the end wall surrounding the receiving groove 102-1a is also provided with a plurality of ribs, one end of which is connected to the first cylinder 102-11. In this way, the ribs can play a role in reinforcing 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 Schematic diagram of the structure of the push rod part and the pressing part in the dose adjustment mechanism.

[0111] In order to enable the push rod portion 101 to move axially and rotate when subjected to a 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, which is rotatably connected to the pressing end of the push rod portion 101.

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

[0113] There is no limitation on the connection method between the pressing portion 105 and the push rod portion 101. For example, in some embodiments of the present application, the push rod portion 101 includes a screw portion, a connecting rod portion, and a spherical connecting portion, the connecting rod portion is connected between the screw portion and the spherical connecting portion, the pressing portion 105 has a spherical connecting groove, the spherical connecting portion is installed inside the spherical connecting groove, and the spherical connecting portion can rotate inside the spherical connecting groove to achieve a rotational connection between the pressing portion 105 and the push rod portion 101; and the diameter of the open end of the spherical connecting groove is smaller than the diameter of the spherical connecting portion, so that the spherical connecting portion can be reliably installed inside the spherical connecting groove without falling out, thereby ensuring a reliable axial connection between the pressing portion 105 and the push rod portion 101.

[0114] The present application also provides an injection device, comprising:

[0115] The barrel 200 has an outlet end and an open end;

[0116] The sealing plug 300 is slidably disposed inside the barrel 200. The area inside the barrel 200 near the discharge end is bounded by the sealing plug 300 to form a storage cavity 200a for storing the injection;

[0117] In the aforementioned dose adjustment mechanism 100 of the injection device, the gripping portion 102 of the dose adjustment mechanism 100 is connected to the open end of the barrel 200 , and the push rod portion 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 described in detail here.

[0119] Among them, there is no restriction on the connection method between the push rod part 101 and the sealing plug 300. 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, the outer diameter of the connecting end of the push rod part 101 is larger 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 a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A dose adjustment mechanism of an injection device, characterized in that: The push rod comprises a push rod portion, a grip portion and a snapping tooth portion, wherein the push rod portion passes through the grip portion and is threadedly connected, the snapping tooth portion is sleeved on the push rod portion and circumferentially limited, the push rod portion can move axially relative to the snapping tooth portion, the grip portion has an accommodating cavity, and the peripheral wall surrounding the accommodating cavity is provided with circumferentially distributed one-way clamping grooves, the snapping tooth portion is located in the accommodating cavity, and the snapping tooth portion has an elastic clamping portion, which is clamped into any one of the one-way clamping grooves; When the push rod part is subjected to pressing force, the push rod part can move axially and drive the tooth part to rotate synchronously under the action of the thread, so that the elastic clamping part slides along the peripheral wall surrounding the accommodating cavity to be clamped into one of the one-way clamping slots at the front end.

2. The dosage adjustment mechanism according to claim 1, characterized in that: The peripheral wall surrounding the accommodating cavity is provided with a plurality of ratchet teeth distributed along the circumferential direction, and ratchet grooves are formed between adjacent ratchet teeth, and the ratchet grooves are the one-way clamping grooves.

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

4. The dosage adjustment mechanism according to any one of claims 1 to 3, characterized in that: The push rod portion has a pressing end, and the end wall of the grip portion facing away from the pressing end is provided with a mounting groove, the mounting groove being used for mounting the raised portion located at the open end of the barrel of the injection device in a transverse limited manner; The dose adjustment mechanism further includes a blocking member connected to the grip portion, and the blocking member is configured to abut against an end wall of the protrusion facing away from the pressing end to limit the axial position of the protrusion.

5. The dosage adjustment mechanism according to claim 4, characterized in that: The end of the holding portion facing away from the pressing end includes two oppositely arranged mounting portions, and the opposite end walls of the two mounting portions form part of the inner wall of the mounting groove. The holding portion is also provided with a mounting hole that passes through the two mounting portions in the transverse direction, and the mounting hole is connected to the mounting groove, and part of the blocking member is fixedly installed in the mounting hole.

6. The dosage 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 with a first end open, 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, and in a non-stressed 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 no greater than the length between the first end of the avoidance opening and the second end of the avoidance opening; When the dose adjustment mechanism and the barrel are in a connected state, both ends of the blocking member are inserted into the mounting holes, 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.

7. The dosage adjustment mechanism according to claim 6, characterized in that: The parts of the blocking member body located on both sides of the notch groove in the width direction are blocking arms, and of the two mounting parts, the mounting part close to the first end is the first mounting part, and the mounting part close to the second end is the second mounting part; the mounting hole includes two first holes arranged on the first mounting part, and a second hole arranged on the second mounting part, 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 dosage adjustment mechanism according to any one of claims 1 to 3, characterized in that: The gripping portion comprises: A main body portion, wherein the main body portion has a receiving groove, an end of the receiving groove close to the pressing end of the push rod portion is an open end, and a peripheral wall surrounding the receiving groove is provided with the one-way clamping groove; A cover portion is connected to the open end of the main body portion, and the accommodating groove forms at least a portion of the accommodating cavity.

9. The dosage adjustment mechanism according to claim 8, characterized in that: The main body comprises a first cylinder disposed inside the receiving groove, an end wall surrounding the receiving groove has a through hole communicating with the first cylinder, and the push rod passes through the first cylinder and is threadedly connected; The ringing tooth portion includes a second cylinder, the elastic clamping portion is connected to the outer peripheral wall of the second cylinder, and the second cylinder has an inwardly folded portion at one end close to the cover portion. The second cylinder is movably fitted onto the first cylinder, and the folded portion faces away from the end wall of the cover portion and abuts against the opposite end of the first cylinder.

10. The dosage adjustment mechanism according to any one of claims 1 to 3, characterized in that: The push rod 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: include: a barrel having a discharge end and an open end; A sealing plug is slidably disposed inside the barrel, with the sealing plug as the boundary, and an area inside the barrel near the discharge end forms a storage cavity, wherein the storage cavity is used to store the injection; The dose adjustment mechanism of the injection device according to any one of claims 1 to 10, wherein the gripping portion of the dose adjustment mechanism is connected to the open end of the barrel, and the push rod portion of the dose adjustment mechanism is connected to the sealing plug.

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