Syringe

Abstract

The invention relates to a syringe. Comprising a shell, an injection push rod, an adjusting knob, a dose scale ring, a push rod sleeve, a scale ring support, a support reset elastic piece, a torsion elastic piece and an injection button, a first external thread is arranged on the outer surface of the injection push rod, and a first internal thread is arranged at the far end of the shell; the adjusting knob is used for setting dosage; the dose scale ring is used for indicating the dose to be injected and can spirally rotate along with the rotation of the adjusting knob; the push rod sleeve can rotate along with the rotation of the adjusting knob; the near end of the scale ring support is provided with a first end face gear ring, and the far end is in circumferential linkage with the push rod sleeve. A second end face gear ring is arranged at the near end of the shell; the support reset elastic piece is used for maintaining meshing of the first end face gear ring and the second end face gear ring. In the working state of setting the dosage, the torsion elastic piece is twisted in the rotation of the adjusting knob; the injection button axially moves towards the far end, and the injector enters an injection working state; according to the technical scheme, the cost of the injector is reduced.

Description

Technical Field

[0001] This application relates to the field of medical devices, and particularly to a syringe. Background Art

[0002] A syringe is a common medical device. As early as the 15th century, the principle of the syringe was obtained. It is mainly used to draw or inject gas or liquid with a needle. Syringes can also be used in medical equipment and drug containers. For example, in some scientific instruments in chromatography, they inject through a rubber diaphragm. A syringe consists of a barrel with a small hole at the front end and a matching piston core rod, used to inject a small amount of liquid or other substances into areas that cannot be accessed by other methods or to draw them out. When the piston core rod is pulled out, the liquid or gas is sucked into the barrel through the small hole at the front end, and when the piston core rod is pushed in, the liquid or gas is extruded.

[0003] For diabetic patients, they need to inject artificial insulin subcutaneously. To avoid contamination of artificial insulin, artificial insulin is contained in a special medicine bottle with a piston provided at one end of the bottle. During injection, the piston at one end of the medicine bottle is pushed by the syringe, and the liquid medicine is extruded from the other end and enters the human body through the needle. Since different diabetic patients have different injection doses, the syringe needs to be provided with a structure for accurately limiting the dose. However, in the prior art, the syringe with an accurately limited dose has the technical problems of complex structure and high manufacturing cost. Summary of the Invention

[0004] In view of this, embodiments of the present application provide a syringe to solve at least one problem in the background art.

[0005] To achieve the above object, the technical solution of the present application is realized as follows:

[0006] Embodiments of the present application provide a syringe, including a housing, an injection push rod, an adjustment knob, a dose scale ring, a push rod sleeve, a scale ring bracket, a bracket reset elastic member, a torsion elastic member, and an injection button, and including two working states of setting the dose and injection, where:

[0007] The housing has a cavity with openings at both ends, including a distal end connected to a drug container and an opposite proximal end;

[0008] The injection push rod is located in the cavity and is used to push the piston in the drug container to move in the injection working state; the outer surface of the injection push rod has a first external thread, and the distal end of the housing is provided with a first internal thread matching the first external thread; in the injection working state, the injection push rod is driven to rotate and forms a helical motion through the cooperation of the first external thread and the first internal thread;

[0009] The adjusting knob is used to set the dose. When it rotates in a first direction around the axis of the injection push rod, the syringe enters the working state of setting the dose.

[0010] The dose scale ring is used to indicate the dose to be injected and can rotate spirally following the rotation of the adjusting knob.

[0011] The push rod sleeve can rotate following the rotation of the adjusting knob. In the working state of setting the dose, the push rod sleeve is circumferentially linked with the dose scale ring. In the working state of injection, the push rod sleeve is circumferentially linked with the injection push rod and the dose scale ring.

[0012] The scale ring bracket is used to transfer the torque of the push rod sleeve to the dose scale ring. A first end face gear ring is arranged at the proximal end of the scale ring bracket, and the distal end is circumferentially linked with the push rod sleeve. A second end face gear ring meshing with the first end face gear ring is arranged at the proximal end of the housing.

[0013] The bracket return elastic member is used to maintain the meshing state of the first end face gear ring and the second end face gear ring and axially abuts against the push rod sleeve.

[0014] The proximal end of the torsion elastic member is connected to the housing, and the distal end is connected to the scale ring bracket. In the working state of setting the dose, the torsion elastic member is torsionally energy-stored during the rotation of the adjusting knob.

[0015] The injection button axially abuts against the push rod sleeve. When the injection button moves axially towards the distal end, the syringe enters the working state of injection. The injection button drives the push rod sleeve to move axially, compressing the bracket return elastic member, so that the first end face gear ring and the second end face gear ring are disengaged from the meshing state, and the scale ring bracket rotates in a second direction under the action of the torsion of the torsion elastic member, driving the push rod sleeve to rotate, and further driving the injection push rod to perform a spiral downward movement for injection.

[0016] Optionally, the syringe further includes:

[0017] A push rod driving member rotatably installed on the inner wall of the distal end of the housing. In the working state of injection, the push rod driving member is circumferentially linked with both the push rod sleeve and the injection push rod to establish the circumferential linkage between the push rod sleeve and the injection push rod.

[0018] Optionally, the meshing edges of the tooth profiles of the first end face gear ring and the second end face gear ring are asymmetric on both sides, so that the rotational resistance of the scale ring bracket in the first direction is less than that in the second direction.

[0019] Optionally, the syringe further includes:

[0020] The first sound - generating device includes a first sound - generating structure and a second sound - generating structure that cooperate with each other; the first sound - generating structure is disposed at the proximal end of the dose scale ring and includes a first groove and an inclined surface extending into the first groove; the second sound - generating structure is disposed at the proximal end of the housing and includes a first protrusion that matches the first groove; in the working state of injection, the dose scale ring rotates spirally until the first protrusion enters the first groove after passing through the inclined surface.

[0021] Optionally, the syringe further includes:

[0022] A dose - accumulating ring, which is installed on the inner wall of the plunger sleeve and sleeved on the injection plunger; in the working state of setting the dose, the rotation of the plunger sleeve drives the dose - accumulating ring to move spirally towards the proximal end until the top end of the dose - accumulating ring abuts against the injection plunger and cannot move spirally upwards; in the working state of injection, the dose - accumulating ring remains axially stationary; when setting the dose, the spiral movement stroke of the dose - accumulating ring on the injection plunger corresponds to the remaining amount of the drug in the drug container.

[0023] Optionally, a first stop block is provided at the distal end of the inner wall of the housing, which limits the distal position of the dose scale ring in the working state of setting the dose, so as to limit the setting of the single - injection dose.

[0024] Optionally, a circumferential second groove is provided at the proximal end of the dose scale ring, and the housing is provided with a second protrusion inserted into the second groove to limit the axial position of the dose scale ring at the zero scale.

[0025] Optionally, the torsion elastic member is a torsion spring, and a hook groove for accommodating the hook of the torsion spring is provided on the inner wall of the housing; the radial width of the hook groove is greater than the radial width of the hook.

[0026] Optionally, the circumferential length of the inner wall of the hook groove abutting against the hook is shorter than the circumferential length of the hook, so that the hook does not contact the housing at the opening of the hook groove.

[0027] Optionally, the housing includes a tube body and a first end ring, and the first end ring is fixed to the inner wall of the proximal end of the tube body; a second end - face gear ring is provided at the distal end of the first end ring.

[0028] Optionally, the housing further includes a second end ring, and the second end ring is fixed to the inner wall of the distal end of the tube body; the second end ring is provided with the first internal thread.

[0029] Optionally, a third groove is provided on the inner wall of the distal end of the tube body, and the third groove extends axially; a third protrusion cooperating with the third groove is provided on the outer wall of the second end ring to limit the circumferential position of the second end ring.

[0030] Optionally, a fourth groove for cooperating with the drug container is provided at the distal end of the tube body to limit the circumferential position of the drug container.

[0031] Optionally, the dose scale ring includes scale marks, and the scale marks include exhaust marks; the exhaust marks are between the zero scale and the maximum scale.

[0032] In the syringe according to the embodiment of the present application, by providing a first end face gear ring on the scale ring bracket, a second end face gear ring on the housing, and a bracket reset elastic member, the position of the dose scale ring in the set dose is maintained stable, without using complex structures such as ratchet arm assemblies, simplifying the structure of the syringe. Therefore, the syringe according to the embodiment of the present application can simplify the structure of the syringe and reduce the cost of the syringe.

[0033] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present application, and constitute a part of the present application. The schematic embodiments and descriptions thereof of the present application are used to explain the present application, and do not constitute an improper limitation of the present application. In the drawings:

[0035] Figure 1 is a schematic external view of the syringe provided by the embodiment of the present application;

[0036] Figure 2 is Figure 1 a cross-sectional view of;

[0037] Figure 3 is Figure 2 a schematic view after removing the drug container;

[0038] Figure 4 is a schematic exploded view of the syringe provided by the embodiment of the present application;

[0039] Figure 5 is a schematic combined view of the main components of the syringe provided by the embodiment of the present application;

[0040] Figure 6 is a schematic view of the injection push rod and the dose accumulation ring in the syringe provided by the embodiment of the present application;

[0041] Figure 7Schematic diagram of the adjustment knob in the syringe provided by the embodiment of the present application;

[0042] Figure 8 Schematic diagram of the push rod sleeve in the syringe provided by the embodiment of the present application;

[0043] Figure 9 A schematic diagram of the dose scale ring in the syringe provided by the embodiment of the present application;

[0044] Figure 10 Schematic diagram of the scale ring bracket in the syringe provided by the embodiment of the present application;

[0045] Figure 11 Schematic diagram of the torsion elastic member in the syringe provided by the embodiment of the present application;

[0046] Figure 12 Schematic diagram of the push rod driving member in the syringe provided by the embodiment of the present application;

[0047] Figure 13 Schematic diagram of a perspective of the first end ring in the syringe provided by the embodiment of the present application;

[0048] Figure 14 Schematic diagram of a perspective of the tube body in the syringe provided by the embodiment of the present application;

[0049] Figure 15 Schematic diagram of the dose scale ring and the first end ring in the syringe provided by the embodiment of the present application;

[0050] Figure 16 For Figure 15 Partial enlarged schematic diagram of some structures in;

[0051] Figure 17 Assembly schematic diagram of the first end ring and the torsion elastic member in the syringe provided by the embodiment of the present application;

[0052] Figure 18 Schematic diagram of the second end ring in the syringe provided by the embodiment of the present application;

[0053] Figure 19 Schematic diagram of another perspective of the tube body in the syringe provided by the embodiment of the present application;

[0054] Figure 20 Connection schematic diagram of the push rod sleeve and the injection button in the syringe provided by the embodiment of the present application;

[0055] Figure 21 For Figure 20 Partial enlarged schematic diagram at position A in;

[0056] Figure 22Another schematic diagram of the dose scale ring in the syringe provided by the embodiment of the present application.

[0057] Explanation of reference numerals:

[0058] 10. Housing; 11. Tube body; 111. Third groove; 112. Fourth groove; 113. Second internal thread; 12. First end ring; 121. Second end face gear ring; 122. First protrusion; 123. Hook groove; 124. Second protrusion; 125. Clamping protrusion; 13. Second end ring; 131. First internal thread; 14. Card slot; 15. Window; 16. First stop block;

[0059] 20. Injection push rod; 21. First external thread; 22. Push rod driving part; 221. Fourth external convex part; 222. First internal plane; 23. First external plane; 24. Dose accumulation ring; 241. Circumferential linkage protrusion; 25. Second stop block;

[0060] 30. Adjusting knob; 31. First internal convex part;

[0061] 40. Dose scale ring; 41. Scale ring bracket; 411. Second internal convex part; 412. First end face gear ring; 413. Third external convex part; 42. Bracket reset elastic part; 43. Second external thread; 44. Third internal convex part; 45. First groove; 46. Inclined plane; 47. Second groove; 48. Exhaust mark;

[0062] 50. Push rod sleeve; 51. First external convex part; 52. Second external convex part; 53. Fourth internal convex part; 54. Circumferential linkage groove; 55. Step hole;

[0063] 60. Torsion elastic part; 61. Hook;

[0064] 70. Injection button; 71. Barbed hook; 72. Button reset spring;

[0065] 80. Drug container; 81. Piston. Detailed implementation manners

[0066] In order to make the technical solutions and beneficial effects of the present application more obvious and understandable, the following will be described in detail by listing specific embodiments. Among them, the drawings are not necessarily drawn to scale, and local features can be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical and scientific fields to which the present application belongs.

[0067] In the description of the present application, the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of simplifying the description of the present application, rather than indicating that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, that is, it cannot be understood as a limitation to the present application.

[0068] In the present application, the terms "first" and "second" are only used for the purpose of clear description and cannot be understood as indicating the relative importance of the indicated features or the quantity of the indicated technical features. Therefore, the features defined with "first" and "second" can clearly include at least one such feature. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc.; the meaning of "several" is at least one, such as one, two, three, etc.; unless otherwise clearly and specifically defined.

[0069] In the present application, unless otherwise clearly defined, terms such as "mounted", "connected", "coupled", "fixed", "arranged", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can also be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0070] In the present application, unless otherwise clearly defined, the first feature being "on", "above", "over" and "upon", "under", "beneath", "below" or "underneath" the second feature can be that the first feature is in direct contact with the second feature, or the first feature and the second feature are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "upon" the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than the horizontal height of the second feature. The first feature being "under", "beneath", "below" and "underneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0071] To thoroughly understand the present application, detailed steps and detailed structures will be presented in the following description to explain the technical solutions of the present application. The preferred embodiments of the present application are described in detail below. However, in addition to these detailed descriptions, the present application may also have other implementation manners.

[0072] In view of the technical problems in the related art, an embodiment of the present application provides a syringe. Refer to Figures 1 - 5 , the syringe includes a housing 10, an injection push rod 20, an adjustment knob 30, a dose scale ring 40, a push rod sleeve 50, a scale ring bracket 41, a bracket return elastic member 42, a torsion elastic member 60, and an injection button 70, and includes two working states: setting the dose and injection. Each component will be introduced one by one below. For the convenience of introduction, the positions and movements of each component are described in the directions shown in Figure 2 , such as up, down, left, right, etc.

[0073] The housing 10 has a cavity with openings at both ends, including a distal end connected to a drug container 80 and an opposite proximal end.

[0074] Understandably, the proximal end can be the Figure 2 right end in Figure 2 , and the distal end can be the

[0075] left end in Figure 6 and Figure 18 . It can be understood that the distal end and the proximal end are relative. For example, the injection push rod 20 is located at the distal end of the adjustment knob 30 but at the proximal end of the drug container 80.

[0076] Understandably, since the syringe is set considering a standard and full-capacity drug container 80, in order to keep the injection dose accurate enough, the drug container 80 installed in the syringe needs to be disassembled from the syringe only after the drug is injected, and cannot be disassembled and reused repeatedly.

[0077] Specifically, the first external thread 21 and the first internal thread 131 can be a kind of transmission thread. More specifically, the first external thread 21 and the first internal thread 131 can be trapezoidal threads.

[0078] The adjustment knob 30 is used to set the dose. When rotating in a first direction around the axis of the injection push rod 20, the syringe enters the working state of setting the dose.

[0079] Understandably, the first direction and the second direction are also relative and are not specifically defined. For example, assuming looking from the proximal end, if the first direction is clockwise, then the second direction is counterclockwise. It can be understood that if the relevant structural settings of the components are adjusted, it can also be: looking from the proximal end, if the first direction is counterclockwise, then the second direction is clockwise.

[0080] Specifically, referring to Figure 7 and Figure 8 , the adjustment knob 30 has a first inner hole, and the inner wall of the first inner hole is provided with a first inner convex member 31 including at least one radial protrusion. The outer wall of the push rod sleeve 50 is provided with a first outer convex member 51 that cooperates with the first inner convex member 31. Through the first inner convex member 31 and the first outer convex member 51, a circumferential linkage relationship is established between the adjustment knob 30 and the push rod sleeve 50. It can be understood that other structures capable of establishing a circumferential linkage can also be used.

[0081] More specifically, the radial protrusions of the first inner convex member 31 and the first outer convex member 51 can be arranged circumferentially, or arranged in a circumferential circle, or include a plurality of protrusions arranged in a circumferential circle.

[0082] More specifically, in order to facilitate the quick switching between forward rotation and reverse rotation, at least one of the first inner convex member 31 and the first outer convex member 51 is provided with: at least two radial protrusions, and the distance between adjacent radial protrusions can only accommodate one radial protrusion of the other convex member.

[0083] The dose scale ring 40 is used to indicate the dose to be injected and can rotate in a spiral manner following the rotation of the adjustment knob 30.

[0084] Specifically, referring to Figure 9 , the outer wall of the dose scale ring 40 is provided with dose numbers arranged in a spiral direction, that is, scales.

[0085] The push rod sleeve 50 can rotate following the rotation of the adjustment knob 30; in the working state of setting the dose, the push rod sleeve 50 is circumferentially linked with the dose scale ring 40; in the working state of injection, the push rod sleeve 50 is circumferentially linked with the injection push rod 20 and the dose scale ring 40.

[0086] Understandably, circumferential linkage means that when one rotates circumferentially, the other also rotates circumferentially, and there is no distinction between the driving and the driven, and it is a two-way linkage.

[0087] Specifically, referring to Figure 9 and Figure 14, the dose scale ring 40 is provided with a second external thread 43, and a second internal thread 113 that mates with the second external thread 43 is provided inside the housing 10. In this way, when the dose scale ring 40 rotates driven by the push rod sleeve 50, the dose scale ring 40 moves up and down in a spiral manner.

[0088] More specifically, in order to make the dose scale ring 40 fit the housing 10 better, the thread of the second external thread 43 is recessed from the outer wall of the dose scale ring 40, and the second internal thread 113 protrudes from the inner wall of the housing 10.

[0089] Specifically, referring to Figure 8 and Figure 10 , at least one second external convex member 52 including a radial protrusion is provided on the outer wall of the push rod sleeve 50, and a second internal convex member 411 that mates with the second external convex member 52 is provided on the inner wall of the scale ring bracket 41. Through the second internal convex member 411 and the second external convex member 52, a circumferential linkage relationship is established between the push rod sleeve 50 and the scale ring bracket 41. It can be understood that other structures capable of establishing a circumferential linkage can also be used.

[0090] More specifically, the radial protrusions of the second internal convex member 411 and the second external convex member 52 can be arranged circumferentially, or arranged in a circumferential circle.

[0091] More specifically, in order to facilitate the quick switching between forward and reverse rotations, at least one of the second internal convex member 411 and the second external convex member 52 is provided with: at least two radial protrusions, and the distance between adjacent radial protrusions can only accommodate one radial protrusion of the other convex member.

[0092] The scale ring bracket 41 is used to transmit the torque of the push rod sleeve 50 to the dose scale ring 40; referring to Figure 10 and Figure 13 , a first end face gear ring 412 is provided at the proximal end of the scale ring bracket 41, and the distal end is circumferentially linked with the push rod sleeve 50; a second end face gear ring 121 that meshes with the first end face gear ring 412 is provided at the proximal end of the housing 10.

[0093] The bracket return elastic member 42 is used to maintain the meshing state of the first end face gear ring 412 and the second end face gear ring 121, and axially abuts against the push rod sleeve 50.

[0094] It can be understood that the axial abutment and meshing of the first end face gear ring 412 and the second end face gear ring 121 can hinder the circumferential rotation of the scale ring bracket 41 to overcome the torque potential energy of the torsion elastic member 60, and maintain the position of the dose scale ring 40 in the dose setting stage when not in the injection stage.

[0095] Specifically, referring to Figure 9and Figure 10 On the outer wall of the scale ring bracket 41, there is a third outer convex member 413 including at least one radial protrusion. On the inner wall of the dose scale ring 40, there is a third inner convex member 44 that cooperates with the third outer convex member 413. Through the third inner convex member 44 and the third outer convex member 413, a circumferential linkage relationship is established between the dose scale ring 40 and the scale ring bracket 41. It can be understood that other structures capable of establishing a circumferential linkage can also be used.

[0096] When a circumferential linkage relationship is established between the push rod sleeve 50 and the scale ring bracket 41, and a circumferential linkage relationship is established between the dose scale ring 40 and the scale ring bracket 41, a circumferential linkage relationship is established between the push rod sleeve 50 and the dose scale ring 40. It can be understood that other structures capable of establishing a circumferential linkage can also be used.

[0097] More specifically, the radial protrusions of the third inner convex member 44 and the third outer convex member 413 can be arranged circumferentially, or arranged in a circumferential circle.

[0098] More specifically, in order to facilitate the quick switching between forward rotation and reverse rotation, at least one of the third inner convex member 44 and the third outer convex member 413 is configured to have at least two radial protrusions, and the distance between adjacent radial protrusions can only accommodate one radial protrusion of the other convex member.

[0099] It can be understood that the bracket return elastic member 42 axially abuts the scale ring bracket 41 to maintain the meshing state of the first end face gear ring 412 and the second end face gear ring 121.

[0100] Specifically, the bracket return elastic member 42 can be a compression spring. The proximal end of the compression spring abuts the third outer convex member 413.

[0101] The proximal end of the torsion elastic member 60 is connected to the housing 10, and the distal end is connected to the scale ring bracket 41; in the working state of setting the dose, the torsion elastic member 60 is torsionally stored during the rotation of the adjustment knob 30.

[0102] Specifically, referring to Figure 11 , the torsion elastic member 60 can be a torsion spring. Connecting portions are provided at both the proximal end and the distal end of the torsion spring. More specifically, the connecting portion can be a hook 61. The connecting portion at the proximal end of the torsion spring is connected to the housing 10, and the connecting portion at the distal end is connected to the scale ring bracket 41.

[0103] The injection button 70 is axially abutted against the push rod sleeve 50; when the injection button 70 moves axially towards the distal end, the syringe enters the working state of injection; the injection button 70 drives the push rod sleeve 50 to move axially, compressing the bracket reset elastic member 42, so that the first end face gear ring 412 and the second end face gear ring 121 are disengaged from the meshing state, and the scale ring bracket 41 rotates in the second direction under the torque action of the torque elastic member 60; driving the push rod sleeve 50 to rotate, and further driving the injection push rod 20 to perform a spiral descending movement for injection.

[0104] Specifically, the injection button 70 is provided with a button return spring 72 to push the injection button 70 to reset after injection is completed.

[0105] It can be understood that the syringe of the embodiment of the present application is a syringe for injecting a set dose, so it includes two working states of setting the dose and injecting, or includes two stages of setting the dose and injecting. The working processes of the two working states are briefly introduced below:

[0106] 1) Setting the dose. Rotate the adjustment knob 30, driving the push rod sleeve 50 to rotate, the push rod sleeve 50 drives the scale ring bracket 41 to rotate, and the scale ring bracket 41 drives the dose scale ring 40 to rotate. Since the dose scale ring 40 is provided with a second external thread 43 and the second internal thread 113 is provided in the housing 10, the dose scale ring 40 spirally rises and falls. Through the transparent or hollow window 15 of the housing 10, the corresponding scale can be seen. Therefore, the required dose can be set by rotating the adjustment knob 30.

[0107] Specifically, before setting the dose, the dose scale ring 40 is located at the proximal end, and the window 15 of the housing 10 displays the "0" scale. The dose scale ring 40 can only move towards the distal end and cannot move in the reverse direction (referred to as the proximal locking position), that is, the adjustment knob 30 can only rotate in the first direction of increasing the dose, that is, rotate forward, and cannot rotate in the reverse direction. Only when the scale is not "0", the adjustment knob 30 can rotate in the second direction of decreasing the dose. For example, when the dose is adjusted beyond the required dose, the dose can be reduced by rotating in the reverse direction, and the dose scale ring 40 moves in the reverse direction, but the resistance of rotating in the reverse direction is greater than the resistance of rotating forward.

[0108] At the same time, the rotation of the scale ring bracket 41 will drive the torque elastic member 60 to rotate, that is, accumulate torque potential energy. And, the second end face gear ring 121 at the proximal end of the housing 10 and the first end face gear ring 412 of the scale ring bracket 41 are kept in the meshing state under the elastic force of the bracket reset elastic member 42. Without external force, the torque potential energy accumulated by the torque elastic member 60 cannot drive the scale ring bracket 41 to rotate in the reverse direction.

[0109] It should be noted that when setting the dose, the injection push rod 20 remains stationary both axially and circumferentially to maintain the accuracy of the injection dose.

[0110] 2) Injection. Press the injection button 70 axially. The injection button 70 axially pushes the push rod sleeve 50 to move axially towards the distal end. The push rod sleeve 50 axially compresses the bracket reset elastic member 42. The first end face gear ring 412 of the scale ring bracket 41 moves towards the distal end. After the bracket reset elastic member 42 is compressed to a certain extent, the first end face gear ring 412 of the scale ring bracket 41 disengages from the second end face gear ring 121 at the proximal end of the housing 10. The torque potential energy of the torsion elastic member 60 is released, driving the scale ring bracket 41 to rotate in the reverse direction. The reverse rotation of the scale ring bracket 41 drives the push rod sleeve 50 to rotate in the reverse direction. The reverse rotation of the push rod sleeve 50 drives the injection push rod 20 to rotate in the reverse direction, causing the injection push rod 20 to move spirally towards the distal end, squeezing the piston 81 in the drug container 80, and injecting the drug.

[0111] At the same time, the dose scale ring 40 also spirally rises and falls following the rotation of the scale ring bracket 41, gradually reducing the scale until the window 15 of the housing 10 returns to the "0" scale and the dose scale ring 40 returns to the proximal locking position. Since the dose scale ring 40 cannot move anymore after returning to the proximal locking position, the torque potential energy of the torsion elastic member 60 cannot drive the scale ring bracket 41 to rotate in the reverse direction anymore. Correspondingly, the torque potential energy stored in the torsion elastic member 60 is also released completely.

[0112] It can be understood that, as described above, only after setting the dose and the window 15 of the housing 10 does not display the "0" scale, that is, the scale is greater than "0", can injection be performed. It can be understood that when the scale is greater than "0", the position of the dose scale ring 40 (referred to as the dose setting position), that is, the spiral lift and lower travel distance from the proximal locking position corresponds to the scale. That is to say, during injection, when the dose scale ring 40 moves from the dose setting position to the proximal locking position, or when the window 15 of the housing 10 changes from the set scale to the "0" scale, the injection push rod 20 can inject the set dose through axial movement to cause the drug container 80 to inject the drug. This requires structural design after calculation to make the movements of the dose scale ring 40 and the injection push rod 20 adapt to each other, such as making the first external thread 21 and the second external thread 43 have appropriate pitches, etc.

[0113] It can be understood that the syringe in the embodiment of the present application needs to be used in cooperation with the drug container 80. The drug container 80 can be a cartridge. The distal end of the cartridge is the drug injection port, and the proximal end is provided with a piston 81, which is generally a rubber stopper. After the drug container 80 is installed on the syringe, the injection push rod 20 is axially connected to the piston 81. In this way, the axial movement of the injection push rod 20 can push the piston 81 to move towards the distal end, squeezing the drug out of the drug injection port. It can be understood that it can also be other types of drug containers.

[0114] In the syringe according to the embodiment of the present application, by providing a first end face gear ring 412 on the scale ring bracket 41, a second end face gear ring 121 on the housing 10, and a bracket return elastic member 42, the position of the dose scale ring 40 in the set dose is maintained stable, without using complex structures such as a ratchet arm assembly, simplifying the structure of the syringe.

[0115] In some other embodiments of the present application, referring to Figure 12 , the syringe further includes:

[0116] A push rod driving member 22 rotatably installed on the inner wall of the distal end of the housing 10; in the working state of injection, the push rod driving member 22 is circumferentially linked with both the push rod sleeve 50 and the injection push rod 20 to establish a circumferential linkage between the push rod sleeve 50 and the injection push rod 20.

[0117] Specifically, in the working state of injection, the push rod sleeve 50 moves distally under the push of the injection button 70. After moving to a certain position, it is circumferentially coupled with the push rod driving member 22 to establish a circumferential linkage relationship. When the push rod sleeve 50 is driven to rotate by the scale ring bracket 41, the push rod driving member 22 rotates following the push rod sleeve 50. And there is a circumferential linkage relationship between the push rod driving member 22 and the injection push rod 20. Therefore, the rotation of the push rod driving member 22 will drive the rotation of the injection push rod 20. Coupled with the cooperation of the first external thread 21 and the first internal thread 131 introduced above, the injection push rod 20 makes a spiral rotation motion.

[0118] Specifically, referring to Figure 8 and Figure 12 , the inner wall of the push rod sleeve 50 is provided with a fourth inner convex member 53 including at least one radial protrusion, and the outer wall of the push rod driving member 22 is provided with a fourth outer convex member 221 cooperating with the fourth inner convex member 53. Through the fourth inner convex member 53 and the fourth outer convex member 221, a circumferential linkage relationship is established between the push rod sleeve 50 and the push rod driving member 22. It can be understood that other structures capable of establishing a circumferential linkage can also be used.

[0119] More specifically, the radial protrusions of the fourth inner convex member 53 and the fourth outer convex member 221 can be arranged circumferentially, or arranged in a circumferential circle.

[0120] More specifically, in order to facilitate the quick switching between forward rotation and reverse rotation, at least one of the fourth inner convex member 53 and the fourth outer convex member 221 is provided with: at least two radial protrusions, and the distance between adjacent radial protrusions can only accommodate one radial protrusion of the other convex member.

[0121] Specifically, at least one first outer plane 23 is provided on the outer circumferential surface of the injection push rod 20. The push rod driving member 22 has a second inner hole and is sleeved on the push rod. At least one first inner plane 222 that cooperates with the first outer plane 23 is provided on the inner wall of the second inner hole. Through the first outer plane 23 and the first inner plane 222, a circumferential linkage relationship is established between the injection push rod 20 and the push rod driving member 22.

[0122] More specifically, two symmetrical first outer planes 23 can be provided on the outer circumferential surface of the injection push rod 20. Correspondingly, two first inner planes 222 are also provided in the second inner hole, forming a kidney-shaped hole.

[0123] It should be noted that in the working state of setting the dose, the axial position of the push rod sleeve 50 remains stationary, and the push rod driving member 22 is not circumferentially linked with the push rod sleeve 50. As a result, a circumferential linkage cannot be established between the push rod sleeve 50 and the injection push rod 20. In this way, when setting the dose, the push rod sleeve 50 rotates and drives the scale ring bracket 41 to rotate, and then drives the scale disk to rotate, while the injection push rod 20 remains stationary.

[0124] In some other embodiments of the present application, referring to Figure 10 and Figure 13 , the meshing edges of the tooth profiles of the first end face gear ring 412 and the second end face gear ring 121 are asymmetrical on both sides, so that the rotational resistance of the scale ring bracket 41 in the first direction is less than the rotational resistance in the second direction.

[0125] Specifically, the tooth profiles of the first end face gear ring 412 and the second end face gear ring 121 can be non-isosceles trapezoids. In this way, the strength of a single tooth is higher. It can be understood that other shapes can also be used, such as non-isosceles triangles.

[0126] It can be understood that in this embodiment, when viewed from the proximal end, the resistance of the scale ring bracket 41 to rotate clockwise is less than the resistance to rotate counterclockwise (the housing 10 is fixed, that is, Figure 13 the first end ring 12 in

[0127] is fixed). Therefore, in this embodiment, the first direction is the clockwise direction when viewed from the proximal end, and the second direction is the counterclockwise direction when viewed from the proximal end. It can be understood that the opposite can also be true, and other components can be designed accordingly. Furthermore, the meshing edges of the tooth profiles of the first end face gear ring 412 and the second end face gear ring 121 are asymmetrical on both sides. In addition to the different rotational resistances for forward and reverse rotations, the sounds for forward and reverse rotations are also different. This prompts the user whether the current operation is forward or reverse, reducing operation errors.

[0128] Specifically, the inclination angle of one meshing edge of the first end face gear ring 412 and the second end face gear ring 121 is 10°-45°, and the inclination angle of the other meshing edge is 60°-90°.

[0129] In some other embodiments of the present application, referring to Figure 9 , Figure 15 and Figure 16 , the syringe further includes:

[0130] A first sound generating device, including a first sound generating structure and a second sound generating structure that cooperate with each other; the first sound generating structure is disposed at the proximal end of the dose scale ring 40 and includes a first groove 45 and an inclined surface 46 extending to the first groove 45; the second sound generating structure is disposed at the proximal end of the housing 10 and includes a first protrusion 122 that matches the first groove 45; in the working state of injection, the dose scale ring 40 rotates in a spiral manner until the first protrusion 122 enters the first groove 45 after passing through the inclined surface 46.

[0131] It can be understood that in the final stage when the injection is about to be completed, the dose scale ring 40 rotates in a spiral manner, the inclined surface 46 abuts against the first protrusion 122, and forces the first protrusion 122 to deform during the spiral rotation. As the dose scale ring 40 continues to rotate, the first protrusion 122 falls into the first groove 45, and the deformed part of the first protrusion 122 that has been compressed is released, emitting a sound different from that during injection to prompt the user that the injection is completed.

[0132] Specifically, the deformation amount of the first protrusion 122 being compressed and deformed can be 0.3-1.2 mm.

[0133] It can be understood that the cooperation between the first groove 45 and the first protrusion 122 can not only generate a sound but also play a certain role in restricting the circumferential position of the dose scale ring 40.

[0134] In some other embodiments of the present application, referring to Figure 6 , the syringe further includes:

[0135] A dose accumulation ring 24, installed on the inner wall of the push rod sleeve 50 and sleeved on the injection push rod 20; in the working state of setting the dose, the rotation of the push rod sleeve 50 drives the dose accumulation ring 24 to move spirally towards the proximal end until the top end of the dose accumulation ring 24 abuts against the injection push rod 20 and cannot move spirally upwards; in the working state of injection, the dose accumulation ring 24 remains axially stationary; when setting the dose, the spiral movement stroke of the dose accumulation ring 24 on the injection push rod 20 corresponds to the remaining amount of the drug in the drug container 80.

[0136] It should be noted that a radially protruding second stop block 25 is provided at the proximal end of the injection push rod 20. In the initial state before use, the distance between the proximal end of the dose accumulation ring 24 and the distal end of the second stop block 25 is a set first axial distance, which is adapted to the capacity of the drug container 80 that mates with the syringe and also determines the maximum injection dose of the syringe.

[0137] Specifically, in order to improve the injection accuracy and facilitate portability in this embodiment, the set dose for a single injection is less than the capacity of the drug container 80. In addition, after installing a drug container 80 on the syringe, it can be injected multiple times without installing a new drug container 80 each time, which also facilitates the user. The following is an example.

[0138] For example, a commonly used drug container 80 has a capacity of 3 ml, and the single injection volume of the syringe in this embodiment is 0.75 ml, that is, it needs to be injected 4 times to inject all the drugs in the drug container 80. When setting a dose of 0.75 ml for the first time, the dose accumulation ring 24 moves spirally towards the proximal end following the rotation of the push rod sleeve 50 and stops after moving 1 / 4 of the maximum stroke, that is, the distance between the dose accumulation ring 24 and the injection push rod 20 is 3 / 4 of the first axial distance. And during the first injection, since the injection push rod 20 also makes a spiral movement in the same direction as the dose accumulation ring 24, the axial distance between the two remains unchanged. After setting a dose of 75 ml for the next time, the distance between the dose accumulation ring 24 and the injection push rod 20 is 2 / 4 of the first axial distance. When setting a dose of 75 ml for the last time, the distance between the dose accumulation ring 24 and the injection push rod 20 is "0", completing the maximum injection dose, and the drug container 80 is also disassembled and discarded.

[0139] It can be understood that the dose set each time can be less than 0.75 ml, so that the number of injections is greater than 4 times.

[0140] Through the dose accumulation ring 24, it is possible to prevent the set dose from exceeding the remaining drug amount in the drug container 80.

[0141] Specifically, a circumferential linkage groove 54 is provided on the inner wall of the push rod sleeve 50, and a circumferential linkage protrusion 241 that mates with the circumferential linkage groove 54 is provided on the outer wall of the dose accumulation ring 24. Through the circumferential linkage groove 54 and the circumferential linkage protrusion 241, a circumferential linkage relationship is established between the push rod sleeve 50 and the dose accumulation ring 24. It can be understood that other structures capable of establishing circumferential linkage can also be used.

[0142] Specifically, the circumferential linkage groove 54 and the fourth inner convex member 53 are axially offset to avoid interference with each other.

[0143] In some other embodiments of the present application, refer to Figure 14, a first stopper 16 is provided at the distal end of the inner wall of the housing 10, and in the working state of setting the dose, the distal position of the dose scale ring 40 is restricted to limit the setting of the single injection dose.

[0144] As described above, in the working state of setting the dose, the dose scale ring 40 moves spirally towards the distal end to limit the single injection dose. A first stopper 16 is provided at the distal end of the housing 10 to axially block the spiral movement of the dose scale ring 40 so that the maximum set scale does not exceed the design value.

[0145] In some other embodiments of the present application, referring to Figure 16 , a circumferential second groove 47 is provided at the proximal end of the dose scale ring 40, and the housing 10 is provided with a second protrusion 124 inserted into the second groove 47 to limit the axial position of the dose scale ring 40 at the zero scale.

[0146] It can be understood that when the second protrusion 124 enters the second groove 47 and abuts circumferentially, the dose scale ring 40 is at the zero scale, or in other words, the window 15 of the housing 10 displays the zero scale. Through the second groove 47 and the second protrusion 124, the dose scale ring 40 can be more reliably maintained at the zero scale position.

[0147] It should be noted that since the dose scale ring 40 and the housing 10 are threadedly connected through a second external thread 43 and a second internal thread 113, and the number of threads of the second internal thread 113 is relatively small, the limiting effect of the second groove 47 and the second protrusion 124 can also prevent the second external thread 43 and the second internal thread 113 from disengaging from the threaded connection.

[0148] It should be noted that the time point when the second protrusion 124 enters the second groove 47 and abuts circumferentially occurs after the first sound generating device emits a sound to prevent the first sound generating device from being unable to emit a sound. And at the first moment after the first sound generating device emits a sound, the second protrusion 124 enters the second groove 47 and abuts circumferentially. That is, the two time points are next to each other, so as to improve the injection accuracy of the syringe.

[0149] In some other embodiments of the present application, referring to Figure 17 , the torsion elastic member 60 is a torsion spring, and the inner wall of the housing 10 is provided with a hook groove 123 for accommodating the hook 61 of the torsion spring; the radial width of the hook groove 123 is greater than the radial width of the hook 61.

[0150] In this way, the installation space for installing the torsion spring into the hook groove 123 is increased, and the installation difficulty of the torsion spring is reduced. And it can also increase the deformation space of the torsion spring when the torsion spring is stressed, and reduce the situation that the syringe fails due to the torsion spring exploding when stressed.

[0151] Specifically, the radial width of the hook groove 123 is greater than the radial width of the hook 61 by 1.4 - 1.8 mm

[0152] In some other embodiments of the present application, referring to Figure 17 , the circumferential length of the inner wall of the hook groove 123 abutting against the hook 61 is shorter than the circumferential length of the hook 61, so that the hook 61 does not contact the housing 10 at the opening of the hook groove 123.

[0153] In this way, the movement of the root of the torsion spring hook 61 is not restricted, the deformation space of the torsion spring is increased, and the situation where the syringe fails due to the torsion spring exploding when stressed is reduced. It can also reduce the damage caused by the torsion spring deforming under force and squeezing the housing 10.

[0154] In some other embodiments of the present application, referring to Figure 4 , the housing 10 includes a tube body 11 and a first end ring 12, and the first end ring 12 is fixed to the inner wall of the proximal end of the tube body 11; a second end face gear ring 121 is provided at the distal end of the first end ring 12.

[0155] That is, the second end face gear ring 121 is not directly machined on the housing 10, but the housing 10 is divided into a tube body 11 and a first end ring 12, and the second end face gear ring 121 is provided on the first end ring 12. In this way, it is more convenient for processing and assembly. It can be understood that the first end ring 12 can also be integrally formed with the tube body 11.

[0156] Furthermore, the first protrusion 122, the second protrusion 124 and the hook groove 123 are also provided on the first end ring 12, so that it is more convenient for processing and assembly.

[0157] In some other embodiments of the present application, referring to Figure 4 , the housing 10 further includes a second end ring 13, and the second end ring 13 is fixed to the inner wall of the distal end of the tube body 11; a first internal thread 131 is provided on the second end ring 13.

[0158] Similarly, in this way, it is more convenient for processing and assembly. It can be understood that the second end ring 13 can also be integrally formed with the tube body 11.

[0159] In some other embodiments of the present application, referring to Figure 19 , a third groove 111 is provided on the inner wall of the distal end of the tube body 11, and the third groove 111 extends axially; a third protrusion is provided on the outer wall of the second end ring 13 to cooperate with the third groove 111 to limit the circumferential position of the second end ring 13.

[0160] In this way, the circumferential position of the second end ring 13 can be better restricted, and the structure is simple with low processing cost.

[0161] In some other embodiments of the present application, referring to Figure 19 , a fourth groove 112 for cooperating with the drug container 80 is provided at the distal end of the tube body 11 to restrict the circumferential position of the drug container 80.

[0162] In this way, the circumferential position of the drug container 80 can be better restricted, and the structure is simple with low processing cost.

[0163] Specifically, the fourth groove 112 and the third groove 111 are circumferentially aligned and axially arranged in sequence. In this way, the processing of the tube body 11 is more convenient.

[0164] In some other embodiments of the present application, referring to Figure 5 and Figure 22 , the dose scale ring 40 includes scale marks, and the scale marks include an exhaust mark 48; the exhaust mark 48 is between the zero scale and the maximum scale.

[0165] In this way, the gas in the drug container 80 can be discharged before injection, making it safer to use.

[0166] Specifically, by setting the dose, the dose scale is rotated to the exhaust mark 48, and then injection is performed. After the injection is completed, by setting the dose again, the dose scale is rotated to the exhaust mark 48 for injection, and the operation is repeated several times to complete the exhaust. After that, normal dose setting and injection can be started.

[0167] In some other embodiments of the present application, a snap connection structure is provided between the tube body 11 and the first end ring 12 to make the axial connection more stable. Referring to Figure 13 and Figure 19 , the snap connection structure includes a convex 125 and a groove 14, and the convex 125 is snapped into the groove 14 to complete the connection.

[0168] In some other embodiments of the present application, referring to Figure 20 and Figure 21 an axially connected barb 71 connection structure is provided between the injection button 70 and the push rod sleeve 50 to make the axial connection more stable. Referring to Figure 20 and Figure 21 , the barb 71 connection structure includes a barb 71 and a stepped hole 55. The stepped hole 55 includes a first through hole and a second through hole with a diameter larger than the first through hole. The barb 71 passes through the first through hole and enters the second through hole, and the connection is completed by the barb 71 hooking the shoulder between the two through holes.

[0169] It should be understood that the above embodiments are all exemplary and do not cover all possible implementation manners included in the claims. Without departing from the scope of the present disclosure, various deformations and changes can also be made on the basis of the above embodiments. Similarly, the technical features of the above embodiments can also be arbitrarily combined to form additional embodiments of the present application that may not be explicitly described. Therefore, the above embodiments only represent several implementation manners of the present application and do not limit the protection scope of the patent of the present application.

Claims

1. A syringe, characterized in that: It includes a housing, an injection push rod, an adjustment knob, a dosage scale ring, a push rod sleeve, a scale ring bracket, a bracket reset elastic member, a torsion elastic member and an injection button, and includes two working states: setting dosage and injection, wherein: The housing has a cavity with two open ends, including a distal end connected to the drug container and an opposite proximal end; The injection push rod is located in the cavity and is used to push the piston in the drug container to move in the injection working state; the outer surface of the injection push rod has a first external thread, and the distal end of the shell is provided with a first internal thread matching the first external thread; in the injection working state, the injection push rod is driven to rotate, and a spiral motion is formed by the cooperation of the first external thread and the first internal thread; The adjusting knob is used to set the dose. When the adjusting knob is rotated in a first direction around the axis of the injection push rod, the injector enters a working state for setting the dose. The dosage scale ring is used to indicate the dosage to be injected, and can spirally rotate following the rotation of the adjustment knob; The push rod sleeve can rotate along with the rotation of the adjusting knob; in the working state of setting the dose, the push rod sleeve is circumferentially linked with the dose scale ring; in the working state of injection, the push rod sleeve is circumferentially linked with the injection push rod and the dose scale ring; The scale ring bracket is used to transmit the torque of the push rod sleeve to the dose scale ring; the proximal end of the scale ring bracket is provided with a first end face gear ring, and the distal end is circumferentially linked with the push rod sleeve; the proximal end of the housing is provided with a second end face gear ring meshing with the first end face gear ring; The bracket reset elastic member is used to maintain the meshing state of the first end face gear ring and the second end face gear ring, and is axially abutted against the push rod sleeve; The proximal end of the torsion elastic member is connected to the housing, and the distal end is connected to the scale ring bracket; in the working state of setting the dose, the torsion elastic member is twisted and stores energy during the rotation of the adjusting knob; The injection button is axially abutted against the push rod sleeve; the injection button moves axially toward the distal end, and the syringe enters an injection working state; the injection button drives the push rod sleeve to move axially, compresses the bracket reset elastic member, so that the first end face gear ring and the second end face gear ring are disengaged, and the scale ring bracket rotates in the second direction under the torsion of the torsion elastic member; drives the push rod sleeve to rotate, and then drives the injection push rod to perform a spiral descending motion for injection.

2. The syringe according to claim 1, characterized in that The syringe also includes: A push rod driving member is rotatably mounted on the inner wall of the distal end of the housing; in the injection working state, the push rod driving member is circumferentially linked with the push rod sleeve and the injection push rod to establish circumferential linkage between the push rod sleeve and the injection push rod.

3. The syringe according to claim 1, characterized in that The meshing edges of the tooth shapes of the first end face gear ring and the second end face gear ring are asymmetric on both sides, so that the rotational resistance of the scale ring bracket in the first direction is smaller than the rotational resistance in the second direction.

4. The syringe according to claim 1, characterized in that The syringe also includes: The first sound-emitting device comprises a first sound-emitting structure and a second sound-emitting structure which cooperate with each other; the first sound-emitting structure is arranged at the proximal end of the dose scale ring, and comprises a first groove and an inclined surface extending to the first groove; the second sound-emitting structure is arranged at the proximal end of the shell, and comprises a first protrusion which matches the first groove; in the working state of injection, the dose scale ring spirally rotates until the first protrusion passes through the inclined surface and enters the first groove.

5. The syringe according to claim 1, characterized in that The syringe also includes: A dose accumulation ring is mounted on the inner wall of the push rod sleeve and sleeved on the injection push rod; in the working state of setting the dose, the rotation of the push rod sleeve drives the dose accumulation ring to spirally move toward the proximal end until the top of the dose accumulation ring abuts against the injection push rod and cannot spirally move upward; in the working state of injection, the dose accumulation ring remains axially stationary; when setting the dose, the stroke of the dose accumulation ring that can spirally move on the injection push rod corresponds to the amount of medicine remaining in the medicine container.

6. The syringe according to claim 1, characterized in that A first stopper is provided at the distal end of the inner wall of the housing, which limits the distal end position of the dose scale ring in a dose setting working state to limit the setting of a single injection dose.

7. The syringe according to claim 1, characterized in that A second circumferential groove is formed at the proximal end of the dose scale ring, and the housing is provided with a second protrusion inserted into the second groove to limit the axial position of the dose scale ring at the zero scale.

8. The syringe according to claim 1, characterized in that The torsion elastic member is a torsion spring, and the inner wall of the shell is provided with a hook groove for accommodating a hook of the torsion spring; the radial width of the hook groove is greater than the radial width of the hook.

9. The syringe according to claim 8, characterized in that The circumferential length of the inner wall of the hook groove abutting against the hook is shorter than the circumferential length of the hook, so that the hook does not contact the housing at the opening of the hook groove.

10. The syringe according to claim 1, characterized in that The shell includes a tube body and a first end ring, wherein the first end ring is fixed to the inner wall of the proximal end of the tube body; the distal end of the first end ring is provided with the second end face gear ring.

11. The syringe according to claim 10, characterized in that The shell further comprises a second end ring, which is fixed to the inner wall of the distal end of the tube body; the second end ring is provided with the first internal thread.

12. The syringe according to claim 11, characterized in that The inner wall of the distal end of the tube body is provided with a third groove, and the third groove extends axially; the outer wall of the second end ring is provided with a third protrusion that cooperates with the third groove to limit the circumferential position of the second end ring.

13. The syringe according to claim 10, characterized in that The distal end of the tube body is provided with a fourth groove matched with the drug container to limit the circumferential position of the drug container.

14. The syringe according to claim 1, characterized in that The dosage scale ring includes scale markings, and the scale markings include an exhaust mark; the exhaust mark is between the zero scale and the maximum scale.

Images