Dose adjustment mechanism of injection device and injection device

Abstract

The present application relates to the field of medical device technology, and specifically to a dose adjustment mechanism and injection device for an injection device, wherein a push rod portion passes through a grip portion and is circumferentially limited. The push rod portion is axially movable relative to the grip portion. A snap tooth portion is fitted over the push rod portion and threadedly connected. The grip portion has a receiving cavity, and the circumferential wall surrounding the receiving cavity is provided with circumferentially distributed one-way slots. The snap tooth portion is located in the receiving cavity and has an elastic snap portion that snaps into any one-way slot. When the push rod portion is subjected to a pressing force, the push rod portion can move axially, the snap tooth portion can rotate under the action of the thread, and the elastic snap portion slides along the circumferential wall surrounding the receiving cavity to snap into one of the one-way slots at the front end. The present application converts axial displacement control into rotational motion control, discretizing the rotational motion of the snap tooth portion into fixed-angle steps. The axial displacement of the push rod portion in a single step is extremely small, meeting the needs of small-dose injections.

Description

Technical Field

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

[0002] Related technology injection device includes a coat component, a push rod component and a clasp component. The surface of the push rod component has a concave-convex structure distributed continuously along the axial direction. The push rod component is suitable for being connected with the coat component and moving along the axial direction of the coat component. The concave-convex structure is blocked by the clasp component during the movement of the push rod component. The clasp component is arranged at the opening of the first end where the push rod component is connected to the coat component. It is suitable for cooperating with the concave-convex structure on the push rod component during the axial movement of the push rod component along the coat component to block the movement of the push rod component. The distance between adjacent concave-convex structures has a corresponding relationship with the dosage of the injection. Under the cooperation of the concave-convex structure and the clasp component, the dosage of the injection can be accurately controlled by blocking the movement of the push rod component, thereby improving the accuracy of the injection amount of the injection.

[0003] The spacing between adjacent concave-convex structures in the related technology injection device determines the minimum dosage unit. If a smaller dosage is to be achieved, the spacing between adjacent concave-convex structures needs to be shortened. However, due to limitations in processing precision such as machining capabilities, an excessively small spacing may cause the concave-convex structure to be unable to form stably or to be easily worn, resulting in the related technology injection device being only suitable for large-dose injections and unable to meet small-dose injection requirements. Summary of the Invention

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

[0005] To solve the above technical problems, the present application provides a dose adjustment mechanism for an injection device, comprising a push rod portion, a grip portion, and a snapping tooth portion, wherein the push rod portion passes through the grip portion and is circumferentially limited and connected thereto, the push rod portion being able to move axially relative to the grip portion, the snapping tooth portion being sleeved over the push rod portion and threadedly connected thereto, the grip portion having an accommodating cavity, the circumferentially distributed one-way slots being provided on a peripheral wall surrounding the accommodating cavity, the snapping tooth portion being located in the accommodating cavity, the snapping tooth portion having an elastic snapping portion that snaps into any one of the one-way snapping slots;

[0006] When the push rod portion is subjected to pressing force, the push rod portion can move axially, and the tooth portion can rotate under the action of the thread, so that the elastic clamping portion slides along the peripheral wall surrounding the accommodating cavity to be clamped into one of the one-way clamping grooves at the front end.

[0007] Optionally, a 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.

[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 gripping 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 the end of the grip portion facing away from the pressing end is provided with a mounting groove, and the mounting groove is used for mounting the protrusion 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 the two ends of the blocking member are fixedly mounted on the mounting holes.

[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, an annular protrusion is provided on the end wall surrounding the receiving groove and the inner wall of the cover portion, and the push rod portion passes through the inside of the annular protrusion;

[0020] The rattling tooth portion includes a cylindrical portion, which is fitted onto the push rod portion and threadedly connected. The elastic clamping portion is connected to the outer peripheral wall of the cylindrical portion. The axial end portions of the cylindrical portion are located inside the corresponding annular protrusions, and the end walls of the accommodating groove and the opposite ends of the cylindrical portion are in conflict with each other.

[0021] The present application also provides an injection device, comprising:

[0022] a barrel having a discharge end and an open end;

[0023] 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;

[0024] 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.

[0025] The technical effects of this application are as follows:

[0026] This application converts the axial displacement control of the push rod part into the rotational motion control of the tooth part through the precise threaded cooperation between the push rod part and the tooth part. At the same time, the rotational motion of the tooth part is discretized into fixed angle steps through the clamping cooperation of the one-way slots distributed along the circumference and the elastic clamping part. By matching the thread pitch and 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

[0027] Figure 1 This is a schematic structural diagram of a specific embodiment of the dose adjustment mechanism of the injection device provided in this application;

[0028] Figure 2 for Figure 1 Schematic diagram of the structure of the dose adjustment mechanism without the cover plate;

[0029] Figure 3 This is an axial cross-sectional view of a specific embodiment of the injection device provided by the present application;

[0030] Figure 4 for Figure 1 A schematic diagram of the structure of the main body of the dose adjustment mechanism;

[0031] Figure 5 for Figure 1 Schematic diagram of the structure of the tooth part in the dose adjustment mechanism;

[0032] Figure 6 for Figure 1 A schematic diagram of the structure of the grip portion of the dose adjustment mechanism;

[0033] Figure 7 for Figure 3 A schematic diagram of the structure of the gripping portion, blocking member and barrel in the injection device;

[0034] Figure 8 for Figure 7 A schematic diagram of the structure of the middle grip portion and the blocking member;

[0035] Figure 9 for Figure 8 A schematic diagram of the structure of the middle grip portion;

[0036] Figure 10 for Figure 8 A schematic structural diagram of the middle blocking member;

[0037] Figure 11 for Figure 1 A split diagram of the grip portion of the dose adjustment mechanism;

[0038] Figure 12 for Figure 1 a partial cross-sectional view of the dose adjustment mechanism;

[0039] Figure 13 for Figure 5 Schematic diagram of the structure of the second angle of the rattle;

[0040] Figure 14 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 1-14 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; 102-2-cover; 102-A-annular protrusion; 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-sounding tooth portion; 1031-elastic clamping portion; 1032-cylinder portion; 1033-protrusion;

[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 dose adjustment mechanism of the injection device 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 circumferentially limited. The push rod 101 is axially movable relative to the grip 102. The snapping tooth 103 is sleeved onto the push rod 101 and threadedly connected. The grip 102 has a receiving cavity 102a. The circumferentially distributed one-way slots 102b are provided on a peripheral wall of the receiving cavity 102a. The snapping tooth 103 is located in the receiving 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 the tooth part 103 can rotate 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 snapping 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 3It can be seen that 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. With the sealing plug 300 as the boundary, the area inside the barrel 200 near the injection end forms 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 connected along the circumferential limit direction. The push rod portion 101 can be relatively close to the barrel 200. The gripping portion 102 moves axially, that is, when the gripping portion 102 is gripped by the operator and the push rod portion 101 is subjected to pressing force, the push rod portion 101 can move axially but cannot rotate; the snapping tooth portion 103 is fitted onto the push rod portion 101 and threadedly connected, and the gripping portion 102 has a receiving cavity 102a, and the snapping tooth portion 103 is located in the receiving cavity 102a. In this way, when the push rod portion 101 is subjected to pressing force, the push rod portion 101 moves axially and the snapping tooth portion 103 rotates under the action of the thread. When the thread pitch of the push rod portion 101 and the snapping tooth portion 103 is fixed, the rotation angle of the snapping tooth portion 103 strictly corresponds to the axial displacement of the push rod portion 101. For example, the thread pitch of the push rod portion 101 and the snapping tooth portion 103 is 1mm, and the snapping tooth portion 103 is 0. When 103 rotates 360°, the push rod part 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 slot 102b, and the snap tooth part 103 has an elastic snap-fitting part 1031, which is snapped into any one-way slot 102b; in this way, the circumferentially distributed one-way slot 102b discretizes the circumferential motion of the snap tooth part 103, and when the push rod part 101 is subjected to pressing force, the push rod part 101 moves in the axial direction, and the snap tooth part 103 is forced to rotate due to the threaded transmission, and the elastic snap-fitting part 1031 gradually slides out of the current one-way slot 102b along the peripheral wall surrounding the accommodating chamber 102a, and is snapped into the next one-way slot 102b, and the elastic snap-fitting part 1031 slides out of the current one-way slot 102b gradually along the peripheral wall surrounding the accommodating chamber 102a, and is snapped into the next one-way slot 102b. Each time the push rod portion 101 moves through a one-way slot 102b, it moves a fixed distance. It can be seen that 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 clear dosage unit. For example, the thread pitch of the push rod portion 101 and the tooth portion 103 is 1mm, and 12 one-way slots 102b are provided on the peripheral wall surrounding the accommodating cavity 102a. The interval between adjacent one-way slots 102b is 30°. Each time the tooth portion 103 slides over a one-way slot 102b, the movement distance of the push rod portion 101 is the ratio of the pitch to the number of one-way slots, that is, approximately 0.0833mm, breaking through the single minimum injection volume limit of the traditional axial concave-convex structure and meeting the needs of small-dose injection.

[0059] Among them, in the process of the elastic clamping part 1031 gradually sliding 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 of the accommodating cavity 102a will produce a "click" sound, or cause the push rod part 101 to vibrate slightly. 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 vibrations, thereby avoiding 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 pressure, the elastic clamping portion 1031 can only slide one-way along the peripheral wall surrounding the accommodating cavity 102a to engage with the one-way slot 102b at the front end, and cannot slide in the opposite direction, that is, to ensure that the tooth portion 103 can only rotate one-way and cannot rotate 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 pressure and cannot move in the opposite direction. On the one hand, it improves the accuracy of the injection volume and avoids injection errors as much as possible; on the other hand, it avoids the secondary use of the dose adjustment mechanism 100, meets the anti-reuse requirements of disposable medical devices, reduces the risk of cross infection, and improves safety.

[0061] To sum up, the dose adjustment 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 tooth part 103 through the precise threaded cooperation between the push rod part 101 and the tooth part 103, and at the same time, the rotational motion of the tooth part 103 is discretized into fixed angle steps through the snap cooperation of the circumferentially distributed one-way slots 102b and the elastic snap-fitting part 1031. By matching the thread pitch and the number of one-way slots, the single-step axial displacement of the push rod part 101 can be controlled to below an extremely small level, thereby meeting the needs of small-dose injection.

[0062] Please refer to Figure 2 and Figure 4 , Figure 4 for Figure 1 Schematic diagram of the structure of the main body of the dose adjustment mechanism.

[0063] 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. The ratchet grooves 1022 are the aforementioned one-way slots 102b.

[0064] Depend on Figure 4It can be seen that the wall surface of the ratchet 1021 has a blocking surface and an inclined surface, and the inclined surface also forms a guide 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.

[0065] Please refer to Figure 5 , Figure 5 for Figure 1 Schematic diagram of the structure of the tooth part in the dose adjustment mechanism.

[0066] In the embodiment of the present application, the ratchet portion 103 has two elastic clamping portions 1031, and the two elastic clamping portions 1031 are arranged at intervals along the circumferential direction. The two elastic clamping portions 1031 cooperate with the ratchet teeth 1021 distributed along the circumferential direction to achieve one-way locking, which is beneficial to dispersing the load, improving the load-bearing capacity of the dose adjustment mechanism 100 of the embodiment of the present application, and improving the locking accuracy of the push rod portion 101 and the sealing plug 300.

[0067] In some other embodiments of the present application, the rattling tooth portion 103 has at least one elastic clamping portion 1031 .

[0068] The elastic clamping portion 1031 is made of a material capable of generating elastic deformation, such as plastic with a certain elasticity.

[0069] As mentioned above, the push rod portion 101 passes through the grip portion 102 and is circumferentially limited and connected. The push rod portion 101 can move axially relative to the grip portion 102. Specifically, in the embodiment of the present application, 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 gripping portion 102 is provided with a limiting protrusion b, at least part of which is slidably inserted into the corresponding limiting groove a.

[0070] As set up 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 the relative shaking of the push rod part 101 and the holding part 102 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.

[0071] In addition, the limiting groove a is provided on the push rod portion 101, and the limiting protrusion b is provided on the grip portion 102, which can also avoid interference with the threaded fit between the push rod portion 101 and the tooth portion 103, thereby ensuring the normal operation of the dose adjustment mechanism 100 of the embodiment of the present application.

[0072] Please refer to Figure 6 , Figure 6 for Figure 1 Schematic diagram of the structure of the grip part in the dose adjustment mechanism.

[0073] In an embodiment of the present application, the holding portion 102 includes two oppositely arranged limiting protrusions b; correspondingly, the push rod portion 101 includes two back-to-back limiting grooves a. The circumferential limiting connection between the holding portion 102 and the push rod portion 101 is realized through the plug-in cooperation of the two sets of limiting protrusions b and the limiting grooves a, which is beneficial to dispersing the load and further improving the limiting reliability of the holding portion 102 on the push rod portion 101.

[0074] In some other embodiments of the present application, the gripping portion 102 has at least one limiting protrusion b, and the push rod portion 101 has at least one limiting groove a.

[0075] Please refer to Figure 7 and Figure 8 , Figure 7 for Figure 3 A schematic diagram of the structure of the gripping portion, blocking member and barrel in the injection device; Figure 8 for Figure 7 Schematic diagram of the structure of the middle grip and the blocking member.

[0076] In the embodiment of the present application, the push rod portion 101 has a pressing end, and the end 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;

[0077] 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 .

[0078] 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.

[0079] Please refer to Figure 8 and Figure 9 , Figure 9 for Figure 8 Schematic diagram of the structure of the middle grip.

[0080] In some embodiments, the blocking member 104 and the grip portion 102 are connected in the following manner:

[0081] 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 both ends of the blocking member 104 are fixedly mounted on the mounting hole 102d.

[0082] 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 protrusion 201 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 two ends of the blocking member 104 are inserted into the mounting holes 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 protrusion 201 facing away from the pressing end abut against each other to axially limit the protrusion 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 a whole, and ensuring a reliable connection between the barrel 200 and the dose adjustment mechanism 100.

[0083] Both ends of the blocking member 104 are fixedly mounted in the mounting hole 102d. Specifically, in some embodiments, the blocking member 104 and the mounting hole 102d can be fitted with an interference fit, which ensures reliable connection and convenient operation.

[0084] Please refer to Figure 7-10 , Figure 10 for Figure 8Schematic diagram of the structure of the blocking member.

[0085] In the embodiment of the present application, the blocking member 104 includes a blocking member body 1041, which is provided with a notch 1041a with an open 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; in an unstressed state, a second end of the elastic member 1042 extends obliquely in a direction away from the pressing end, 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;

[0086] 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.

[0087] in, Figure 7 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.

[0088] As set 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 continue to move; at the same time, the elastic member 1042 is deformed from the installation hole 1 02d penetrates, thereby releasing the restraining effect 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, 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 that the blocking member 104 reliably limits the axial direction of the barrel 200, and ensuring a reliable connection between the barrel 200 and the dose adjustment mechanism 100.

[0089] Depend on Figure 7It 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 is reliably installed.

[0090] 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.

[0091] 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 abuts against the end wall of the protrusion 201 facing away from the pressing end to limit the axial position of the protrusion 201; the end walls of the two limiting protrusions facing away from the pressing end form an inclined guide wall, and the distance between the two guide walls gradually increases in the direction away from the pressing end. 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.

[0092] Please continue to refer to Figure 7-10 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.

[0093] 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.

[0094] 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 arranged on the first mounting portion 1023-1 and the second hole 102d-2 arranged on the second mounting portion 1023-2 can achieve 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.

[0095] Please refer to Figure 11 , Figure 11 for Figure 1 A detailed diagram of the grip portion of the dose adjustment mechanism.

[0096] In some embodiments of the present application, the grip portion 102 includes:

[0097] 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 a one-way locking groove 102b.

[0098] 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 .

[0099] 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.

[0100] 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.

[0101] like 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.

[0102] At the same time, 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 part 102-2 is provided with the other of the positioning hole e and the positioning column f. During the connection process between the cover part 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.

[0103] Please refer to Figure 12 , Figure 12 for Figure 1 Partial cross-sectional view of the dose adjustment mechanism.

[0104] In some embodiments of the present application, an annular protrusion 102-A is disposed opposite to the end wall of the receiving groove 102-1a and the inner wall of the cover portion 102-2, and the push rod portion 101 passes through the inside of the annular protrusion 102-A;

[0105] The rattling tooth portion 103 includes a cylindrical portion 1032, which is fitted onto the push rod portion 101 and threadedly connected. The elastic clamping portion 1031 is connected to the outer peripheral wall of the cylindrical portion 1032, and the axial end portions of the cylindrical portion 1032 are located inside the corresponding annular protrusion 102-A, forming an end wall of the accommodating groove 102-1a and abutting against the opposite end of the cylindrical portion 1032.

[0106] As configured above, the two annular protrusions 102-A can play a role in positioning the cylindrical portion 1032, thereby improving the installation convenience and positioning accuracy of the rattling tooth portion 103; the end wall forming the accommodating groove 102-1a and the opposite end of the cylindrical portion 1032 interfere with each other, and when the push rod portion 101 is subjected to pressing force, the end wall forming the accommodating groove 102-1a can play a role in axially limiting the rattling tooth portion 103, thereby preventing the axial movement of the rattling tooth portion 103, and thereby enabling the rattling tooth portion 103 to rotate under the action of threaded cooperation.

[0107] In some embodiments, the elastic clamping portion 1031 and the cylindrical portion 1032 may be an integrally formed structure to improve the connection strength between the elastic clamping portion 1031 and the cylindrical portion 1032 .

[0108] Please refer to Figure 12-13 , Figure 13 for Figure 5 Schematic diagram of the structure of the second angle of the rattle part.

[0109] In order to reduce the friction force when the rattling tooth portion 103 rotates, a protrusion 1033 distributed along the circumferential direction is provided at the end of the cylindrical portion 1032 away from the cover portion 102-2, and the end wall of the accommodating groove 102-1a is in contact with the protrusion 1033, thereby reducing the contact area between the end wall of the accommodating groove 102-1a and the cylindrical portion 1032, reducing the friction force when the rattling tooth portion 103 rotates, and making the rattling tooth portion 103 rotate more smoothly.

[0110] Among them, the protrusion 1033 can be a hemispherical structure, which further reduces the contact area between the end wall surrounding the accommodating groove 102-1a and the cylindrical body 1032, and further reduces the friction force when the tooth part 103 rotates.

[0111] Of course, in some other embodiments, it is also feasible to provide a protrusion on the end wall that surrounds the accommodating groove 102-1a. The end wall that surrounds the accommodating groove 102-1a can also reduce the friction force when the tooth portion 103 rotates through the collision between the protrusion and the corresponding end of the cylindrical portion 1032.

[0112] Furthermore, in the dose adjustment mechanism 100 of the present embodiment, the push rod portion 101 can only move unidirectionally under pressure and cannot move in the reverse direction, and thus the snapping tooth portion 103 has no tendency to move in the reverse direction. Therefore, a gap may be provided between the inner wall of the cover portion 102-2 and the corresponding end of the barrel portion 1032 to minimize friction during rotation of the snapping tooth portion 103 and improve smooth rotation of the snapping tooth portion 103.

[0113] Please refer to Figure 14 , Figure 14 for Figure 1 Schematic diagram of the structure of the push rod part and the pressing part in the dose adjustment mechanism.

[0114] 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 fixedly connected to the pressing end of the push rod portion 101. The cross-sectional area of ​​the pressing portion 105 is larger than the cross-sectional area of ​​the push rod portion 101, which facilitates the operator to apply force and improves operational convenience.

[0115] The connection method of the pressing portion 105 and the push rod portion 101 is not limited, and can be welding, clamping, interference fit, etc. Alternatively, in other embodiments, the pressing portion 105 and the push rod portion 101 are an integrally formed structure.

[0116] The present application also provides an injection device, comprising:

[0117] The barrel 200 has an outlet end and an open end;

[0118] 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;

[0119] 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 .

[0120] 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.

[0121] 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.

[0122] 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 circumferentially limited and connected thereto, the push rod portion being able to move axially relative to the grip portion, the snapping tooth portion being sleeved on the push rod portion and being threadedly connected thereto, the grip portion having an accommodating cavity, the circumferential wall of which is provided with circumferentially distributed one-way slots, the snapping tooth portion being located in the accommodating cavity, the snapping tooth portion having an elastic snapping portion which snaps into any one of the one-way slots; When the push rod portion is subjected to pressing force, the push rod portion can move axially, and the tooth portion can rotate under the action of the thread, so that the elastic clamping portion slides along the peripheral wall surrounding the accommodating cavity to be clamped into one of the one-way clamping grooves 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 gripping 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 of the grip portion facing away from the pressing end is provided with a mounting groove, and the mounting groove is 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 the two ends of the blocking member are fixedly mounted on the mounting holes.

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 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; 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.

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 end wall surrounding the receiving groove and the inner wall of the cover portion are oppositely provided with an annular protrusion, and the push rod portion passes through the inside of the annular protrusion; The rattling tooth portion includes a cylindrical portion, which is fitted onto the push rod portion and threadedly connected. The elastic clamping portion is connected to the outer peripheral wall of the cylindrical portion. The axial end portions of the cylindrical portion are located inside the corresponding annular protrusions, and the end walls of the accommodating groove and the opposite ends of the cylindrical portion are in conflict with each other.

10. 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 9, 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.

Images