Triggering device for syringe and syringe

Abstract

This utility model provides a triggering device for a syringe and the syringe thereof, belonging to the technical field of medical devices. The triggering device includes: a pressing part disposed at the syringe push end, comprising an axially arranged limiting post and a circumferentially arranged rotating groove; a rotating part, a centrally hollowed-out column sleeved on the limiting post, including a first meshing tooth arranged circumferentially at a first end and a ratchet arranged circumferentially at a second end; a push rod, including a limiting groove at the center of one end and a second meshing tooth arranged circumferentially, the limiting groove abutting against the limiting post, and the other end connected to a drug capsule inside the syringe; before injection, the first and second meshing teeth engage and fix the push rod, preventing circumferential rotation; during injection, pressing the pressing part disengages the second meshing tooth from the first meshing tooth and the ratchet engages with the rotating groove, rotating the rotating part drives the pressing part to push the push rod axially to push the drug capsule. This triggering device effectively avoids accidental triggering and circumferential rotation of the push rod.

Description

Technical Field

[0001] This utility model belongs to the technical field of medical devices, and specifically relates to a triggering device for a syringe and the syringe thereof. Background Technology

[0002] Subcutaneous injection of medications via syringe is a common method of drug administration. For example, insulin injectors used by diabetic patients deliver a capsule containing a measured amount of artificial insulin subcutaneously through an internal syringe delivery mechanism to regulate blood sugar.

[0003] Because the delivery mechanism is hidden inside the syringe, an external triggering mechanism is needed to apply force to push the internal delivery mechanism and push the drug capsule. The triggering mechanism must ensure that the internal delivery structure is not accidentally triggered before injection, and that during injection, the internal delivery structure successfully completes the expected path to fully eject the drug capsule, thus achieving quantitative drug injection.

[0004] Existing triggering mechanisms typically use a knob structure connected to a threaded push rod. This type of mechanism is prone to two problems: firstly, it can easily lead to accidental triggering of the internal push rod before use, causing the drug capsule to be released and wasted when not in use; secondly, it can cause the push rod to exert force linearly towards the drug capsule during use, but the actual rotation consumes the pushing force, preventing it from reaching the final push point, thus failing to fully eject the drug capsule and affecting drug injection and treatment efficacy.

[0005] In view of this, there is a need for a new type of triggering device for syringes and a syringe thereof to solve all or part of the above problems. Utility Model Content

[0006] To address at least one of the aforementioned problems and defects in the prior art, embodiments of this utility model provide a triggering device for a syringe and the syringe thereof. By nesting a rotating part between a pressing part and a push rod, the syringe is secured to the push rod before use by connecting the first end of the rotating part to prevent circumferential rotation. During use, the nesting of the pressing part and the second end of the rotating part disengages the rotating part from the push rod. The rotating part, in conjunction with the pressing part, then rotates and pushes the push rod to move linearly along the axial direction. The technical solution is as follows:

[0007] According to one aspect of the present invention, a triggering device for a syringe is provided. The triggering device includes:

[0008] The pressing part is located at the pushing end of the syringe, and includes a limiting post arranged along the axial direction and a rotating groove arranged along the circumferential direction.

[0009] The rotating part is a centrally hollowed-out column that is fitted onto the limiting column of the pressing part. The rotating part includes a first meshing tooth arranged circumferentially at its first end and a ratchet arranged circumferentially at its second end.

[0010] The push rod includes a limiting groove at the center of one end and a second meshing tooth arranged circumferentially. The limiting groove abuts against the limiting post of the pressing part, and the other end of the push rod is connected to the drug capsule inside the syringe.

[0011] Before injection, the first meshing tooth of the rotating part engages with the second meshing tooth of the push rod to fix the push rod without circumferential rotation; during injection, after pressing the pressing part, the second meshing tooth of the push rod disengages from the first meshing tooth of the rotating part, and the ratchet of the rotating part is embedded in the rotating groove of the pressing part. Rotating the rotating part drives the pressing part to push the push rod to push the drug capsule axially.

[0012] In some embodiments, specifically, at least one locking key is provided at the center of the limiting post of the pressing part. A latch is provided at the center of the limiting groove of the push rod. At least one locking key engages with the latch to lock and secure the pressing part and the push rod together.

[0013] In some embodiments, preferably, at least two rib grooves are provided on the circumferential surface of the limiting post of the pressing part, and the slotting direction of each of the at least two rib grooves is parallel to the axial direction. At least two support ribs are provided in the limiting groove of the push rod. Each of the at least two rib grooves engages with each of the at least two support ribs.

[0014] In some embodiments, the rotating groove of the pressing part further includes wedge-shaped teeth arranged one by one around the inside of the rotating groove in the same wedge angle direction.

[0015] In some embodiments, specifically, the ratchet of the rotating part includes teeth, the tip shape of each tooth being matched with the gap shape of two adjacent wedge-shaped teeth in the rotating groove of the pressing part. When injection is performed, after pressing the pressing part, the teeth of the ratchet engage in the gap between the adjacent wedge-shaped teeth, and rotating the rotating part causes the pressing part to rotate in a single direction.

[0016] In some embodiments, preferably, the first end of the rotating part further includes at least two ribs arranged circumferentially, which are inserted into the limiting groove of the push rod and abut against at least two support ribs in the limiting groove.

[0017] In some embodiments, preferably, the plunger further includes a positioning key disposed on the cylindrical surface of the plunger. During injection, the plunger moves linearly along the axial direction, and when the positioning key abuts against the locking structure inside the syringe, the plunger completes its pushing stroke and stops moving.

[0018] In some embodiments, preferably, a protruding structure is further provided on the cylindrical surface of the rotating part.

[0019] In some embodiments, preferably, the plunger further includes a sounder for emitting a prompting sound during injection, the sounder being disposed at the end of the plunger that abuts against the pressing portion.

[0020] According to another aspect of the present invention, a syringe is provided. The syringe includes a needle, a drug capsule, a delivery mechanism, a locking mechanism, and a triggering device, which are sequentially connected in series within the syringe housing. The triggering device is the one described in the foregoing aspects.

[0021] The triggering device for a syringe and the syringe thereof provided by the embodiments of this utility model have at least one or a portion of the following advantages:

[0022] (1) By nesting the rotating part between the pressing part and the push rod, the syringe can be fixed to prevent the push rod from rotating circumferentially before use by connecting the first end of the rotating part to the push rod. When in use, the second end of the pressing part and the second end of the rotating part are nested together, so that the rotating part is disengaged from the push rod. The rotating part and the pressing part work together to rotate and push the push rod to move in a straight line along the circumferential direction.

[0023] (2) By cooperating with the limiting post of the pressing part and the limiting groove of the push rod, and by locking the locking key on the limiting post and the buckle on the limiting groove, the fixing between the pressing part and the push rod is strengthened, ensuring that the pressing part can be stably pushed to move linearly when the pressing part is pressed.

[0024] (3) By engaging the first meshing tooth of the rotating part with the second meshing tooth of the push rod, the push rod can be effectively fixed before the syringe is used to prevent it from rotating circumferentially, thereby reducing the assembly error or structural misalignment of the push rod in the syringe;

[0025] (4) By engaging the ratchet of the rotating part with the wedge-shaped teeth inside the rotating groove of the pressing part, the syringe can only rotate in one direction during use, avoiding reverse rotation;

[0026] (5) By setting a rotating part between the pressing part and the push rod, the push rod cannot be pushed even if the pressing part is pressed before the syringe is used, without rotating the rotating part, thereby avoiding accidental triggering before the syringe is used.

[0027] (6) By setting a sound device on the plunger, it can effectively prompt the plunger to push the drug capsule. At the same time, setting a positioning key on the plunger can effectively prompt the plunger in the syringe to complete the pushing stroke. Attached Figure Description

[0028] These and / or other aspects and advantages of this invention will become apparent and readily understood from the following description of preferred embodiments taken in conjunction with the accompanying drawings, in which:

[0029] Figure 1 This is a schematic diagram of the assembly structure of the triggering device in a syringe according to an embodiment of the present invention;

[0030] Figure 2 for Figure 1 A schematic diagram of the structure of a pressing part of the triggering device shown;

[0031] Figure 3 To and Figure 2 The diagram shows a push rod with a matching pressing part.

[0032] Figure 4 To and Figure 2 The pressing part and Figure 3 A schematic diagram of the structure of the first end of a rotating part in a push rod matching configuration;

[0033] Figure 5 for Figure 4 A schematic diagram of the structure of the second end of the rotating part shown;

[0034] Figure 6 This is a schematic diagram of the structure of a syringe according to an embodiment of the present invention. Detailed Implementation

[0035] The technical concept and technical solution of this utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings. In this specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of this utility model with reference to the accompanying drawings is intended to explain the overall concept of this utility model and should not be construed as a limitation thereof.

[0036] It should also be understood that although the terms "first," "second," "third," etc., may be used in the following embodiments of this utility model to describe a component comprising two or more of the same component, these components should not be limited to these terms, which are only used to distinguish each component from one another. Furthermore, descriptions indicating orientation such as "upper," "lower," "left," and "right" are merely illustrative of the relative positions of components and should not be construed as a limitation of this utility model.

[0037] Currently, most subcutaneous drug injectors use pen-type injectors. The process of pushing the drug capsule and needle to complete the injection is analogous to that of a mechanical pencil or a ballpoint pen or water-based pen whose tip is extended by pressing. However, due to the more complex internal structure of the injector and the high quantitative accuracy required for drug delivery and injection, existing press-triggered mechanisms often cannot meet the requirements for precise injection.

[0038] Therefore, the following embodiments of this utility model provide a triggering device for a syringe and a syringe thereof. By nesting a rotating part between the pressing part and the plunger, the plunger can be fixed in place before use by the connection between the first end of the rotating part and the plunger to prevent circumferential rotation. During use, the second end of the pressing part and the rotating part are nested together, causing the rotating part to disengage from the plunger. After the rotating part and the pressing part cooperate, they rotate and push the plunger to move linearly along the axial direction. This effectively avoids accidental activation of the plunger before use or circumferential rotation of the plunger inside the syringe, and ensures that the plunger always maintains linear axial pushing during use, avoiding circumferential rotation that consumes pushing force and ensuring that the plunger completes the complete pushing path to quantitatively push the drug capsule.

[0039] According to one aspect of the present invention, the following embodiments provide a triggering device for a syringe. See also Figure 1 The image shows an assembly structure in which a trigger device 100 is mounted on a syringe 200 according to an embodiment. The trigger device 100 mainly consists of three parts: a pressing part 10, a rotating part 20, and a push rod 30, which are nested together. The push rod 30 is inserted into the push end of the syringe 200 and connected to the drug capsule to be injected.

[0040] Specifically, the pressing part 10 is disposed at the pushing end of the syringe 200, and includes a limiting post 11 disposed axially and a rotating groove 12 disposed circumferentially. The rotating part 20 is a centrally hollowed-out column and is sleeved on the limiting post 11 of the pressing part 10. The rotating part 20 includes a first meshing tooth 21 disposed circumferentially at its first end and a ratchet 22 disposed circumferentially at its second end. The push rod 30 includes a limiting groove 31 disposed at the center of one end and a second meshing tooth 32 disposed circumferentially. The limiting groove 31 abuts against the limiting post 11 of the pressing part 10, and the other end of the push rod 30 is connected to the drug capsule inside the syringe 200.

[0041] Before injection, the first meshing tooth 21 of the rotating part 20 engages with the second meshing tooth 32 of the push rod 30 to fix the push rod 30 without circumferential rotation.

[0042] During injection, after pressing the pressing part 10, the second engaging tooth 32 of the push rod 30 disengages from the first engaging tooth 21 of the rotating part 20, and the ratchet 22 of the rotating part 20 is embedded in the rotating groove 12 of the pressing part 10. Rotating the rotating part 20 drives the pressing part 10 to push the push rod 30 to push the drug capsule axially.

[0043] See Figure 2 The diagram illustrates the specific structure of the pressing part 10 in one embodiment. See also... Figure 3 It shows the relationship with Figure 2The specific structure of the push rod 30 in one embodiment is designed to match the pressing part 10. The pressing part 10 is always in contact with the push rod 30 via the limiting post 11. When injection is required, pressing the pressing part 10 pushes the push rod 30, causing the push rod 30 to disengage from the rotating part 20 and continue to push the push rod 30 toward the needle.

[0044] like Figure 2 As shown, in one example, specifically, at least one latching key 111 is provided at the center of the limiting post 11 of the pressing part 10. Preferably, two latching keys 111 are provided at the center of the limiting post 11.

[0045] In one example, specifically, at least two rib grooves 112 are provided on the circumferential surface of the limiting post 11 of the pressing part 10, and the grooving direction of each of the at least two rib grooves 112 is parallel to the axial direction. That is, at least two rib grooves 112 are actually formed on the wall surface of the limiting post 11 along the pushing direction of the syringe 200. Preferably, the number of at least two rib grooves 112 is four, and the four rib grooves 112 are symmetrically arranged around the circumference.

[0046] like Figure 3 As shown, in one example, a buckle 311 is specifically provided at the center of the limiting groove 31 of the push rod 30. At the same time, at least two support ribs 312 are provided within the limiting groove 31. Preferably, the number of the at least two support ribs 312 is four.

[0047] In one example, preferably, the limiting groove 31 of the push rod 30 is actually a circular cross-section groove. First, a buckle 311 is provided at its center to engage with the limiting post 11 of the pressing part 10. Then, each support rib 312 extends from the outside of the buckle 311 toward the wall of the limiting groove 31. More preferably, four support ribs 312 are provided in a symmetrical arrangement around the circumference to match the four rib grooves 112 on the limiting post 11 of the pressing part 10, and the position of each support rib 312 corresponds one-to-one with the position of each rib groove 112.

[0048] Combination Figure 2 and Figure 3 As shown, at least one locking key 111 (preferably two locking keys 111) provided at the center of the limiting post 11 in the pressing part 10 is inserted and locked with the buckle 311 provided at the center of the limiting groove 31 of the push rod 30, thus fixing the pressing part 10 and the push rod 30 together.

[0049] To further secure the pressing part 10 and the push rod 30 and prevent the push rod 30 from rotating circumferentially during linear motion along the axial direction, each of the at least two grooves 112 (preferably four grooves 112) on the circumferential surface of the limiting post 11 in the pressing part 10 is engaged with each of the at least two support ribs 312 (preferably four support ribs 312 corresponding to the four grooves 112) provided in the limiting groove 31 of the push rod 30.

[0050] In one example, the number and specific arrangement of the aforementioned components for snap-fit ​​fixing, such as the snap-fit ​​key 111 and rib groove 112 on the pressing part 10 and the buckle 311 and support rib 312 on the push rod 30, need to be limited or optimized in accordance with the overall structure of the syringe 200. This example is only an illustrative example and should not be construed as a limitation of the present invention by those skilled in the art.

[0051] In one example, alternatively, the plunger 30 may also include a sound generator 33 for emitting a prompting sound during injection, the sound generator 33 being disposed at the end of the plunger 30 that abuts against the pressing part 10. Further alternatively, the sound generator 33 may be a piezoelectric sound generator, for example, a sound-emitting plate made of piezoelectric materials such as piezoelectric ceramics. When pressure is applied to the sound-emitting plate, an electrical charge is generated, which can be converted into an electrical signal through a circuit setting. By providing an acoustic feedback component that can sense the electrical signal of the sound generator 33 at an appropriate location on the triggering device 100 or the syringe 200, it is possible to achieve the following: when the pressing part 10 pushes the plunger 30, the sound generator 33 within the plunger 30 is subjected to pressure, and an alarming sound indicating that the plunger 30 has begun to push the capsule is emitted via the acoustic feedback component (not shown). This example is merely illustrative and should not be construed as a limitation of the present invention.

[0052] See Figure 4 The diagram illustrates the specific structure of the rotating part 20 according to one embodiment, with particular emphasis on its structure in the direction of its first end. See also... Figure 5 This shows, as Figure 3 The specific structure of the rotating part 20 in the direction of its second end is shown. The first end of the rotating part 20 is... Figure 3 The push rod 30 shown is matched and installed, with the second end connected to... Figure 2 The pressing part 10 shown is matched and installed.

[0053] Combination Figure 3 and Figure 4 As shown, a first meshing tooth 21 is first provided on the end face of the first end of the rotating part 20, and then a second meshing tooth 32 is provided on the end of the push rod 30 where a limit groove 31 is provided.

[0054] In one example, such as Figure 3As shown, preferably, a ring of second meshing teeth 32 is arranged around the periphery of the circumference at one end of the push rod 30 (which is provided with a limiting groove 31).

[0055] Furthermore, in accordance with the second meshing tooth 32, such as Figure 4 As shown, a first meshing tooth 21 that meshes with the second meshing tooth 32 is provided on the end face of the first end of the rotating part 20.

[0056] In one example, alternatively, the first meshing tooth 21 can be configured as several groups of meshing teeth, each group containing several tooth structures. For example... Figure 4 As shown, preferably, three sets of meshing teeth are evenly arranged along the circumferential direction on the end face of the first end of the rotating part 20, and then 3-5 tooth structures are provided in each set of meshing teeth. Each tooth structure can be coupled with... Figure 3 The corresponding tooth structure of the second meshing tooth 32 on the push rod 30 shown is engaged. This example is merely illustrative and should not be construed as a limitation of the present invention by those skilled in the art.

[0057] In one example, alternatively, the first end of the rotating part 20 may also include at least two rib keys 23 arranged circumferentially, which are inserted into the limiting groove 31 of the push rod 30 and abut against at least two support ribs 312 in the limiting groove 31.

[0058] More preferably, in accordance with the aforementioned provision of four support ribs 312 in the limiting groove 31 of the push rod 30, four to eight rib keys 23 can be evenly provided on the wall surface of the central through hole of the rotating part 20. The push rod 30 is further fixed by the contact between each rib key 23 and each support rib 312 to prevent it from rotating circumferentially.

[0059] Combination Figure 2 and Figure 5 As shown, a ratchet 22 is first provided on the end face of the second end of the rotating part 20, and then a rotating groove 12 that is embedded and matched with the ratchet 22 is provided on the inner side of the pressing part 10 along the circumferential periphery.

[0060] In one example, such as Figure 2 As shown, preferably, the rotating groove 12 of the pressing part 10 further includes wedge-shaped teeth 121, which are arranged one by one around the inside of the rotating groove 12 in the same wedge angle direction along the circumference. Specifically, one end of the wedge-shaped tooth 121 is narrower and the other end is wider. Therefore, when arranging each wedge-shaped tooth 121 in the rotating groove 12, it is necessary to ensure that the wider end of each wedge-shaped tooth 121 is connected to the narrower end of its adjacent wedge-shaped tooth 121 until the wedge-shaped teeth 121 are arranged around the entire rotating groove 12.

[0061] Furthermore, in accordance with the wedge-shaped teeth 121 of the rotating groove 12, such as Figure 5 As shown, a ratchet 22 is provided at the second end of the rotating part 20.

[0062] In one example, preferably, the ratchet 22 of the rotating part 20 uses a set of one-way ratchets, each of which includes teeth 221. The tooth tip shape of each tooth 221 matches the gap shape of two adjacent wedge-shaped teeth 121 in the rotating groove 12 of the pressing part 10. That is, the teeth 221 of the ratchet 22 need to be engaged in the gap between the wedge-shaped teeth 121 in the rotating groove 12, so that by rotating the rotating part 20, the teeth 221 of the ratchet 22 inside it push the wedge-shaped teeth 121 in the rotating groove 12 of the pressing part 10 to rotate together. Furthermore, the engagement between the ratchet 22 and the wedge-shaped teeth 121 ensures that the rotation direction can only have one direction and cannot be reversed. This arrangement locks the rotation pushing direction, so that the pressing part 10 pushes the push rod 30 to always move axially in a straight line from the pushing end to the injection end.

[0063] In one example, the rotating groove 12 of the pressing part 10 has a certain depth, that is, the wedge teeth 121 on the rotating groove 12 have a certain height, so that after the ratchet 22 of the rotating part 20 is inserted into the rotating groove 12 of the pressing part 10, it needs to slide a certain distance on the surface of the wedge teeth 121 before it is fully inserted into the interior of the pressing part 10.

[0064] When the syringe 200 is not in use, although the pressing part 10 is always engaged with the push rod 30, the rotating part 20 (first end) is also fixed to the push rod 30. Furthermore, the push rod 30 can be fixed in the circumferential direction and cannot rotate by the engagement of the first meshing tooth 21 and the second meshing tooth 32.

[0065] Even if the pressing part 10 is accidentally touched at this time, the first end of the rotating part 20 will disengage from the push rod 30, and its second end will be engaged with the pressing part 10. Since the second end of the rotating part 20 is engaged and locked with the wedge-shaped teeth 121 of the rotating groove 12 inside the pressing part 10 through the ratchet 22, the pressing part 10 cannot continue to push the push rod 30 when the rotating part 20 is not rotating, so that the accidentally touched pressing part 10 cannot continue to push the push rod 30 to the injection end.

[0066] This configuration ensures that the plunger 30 will not rotate circumferentially or move axially before the syringe 200 is used, and that the plunger 30 will not move axially when the pressing part 10 is accidentally touched.

[0067] When the syringe 200 is needed for drug injection, after pressing the pressing part 10, the first engaging tooth 21 at the first end of the rotating part 20 disengages from the second engaging tooth 32 of the push rod 30 as the pressing part 10 pushes the push rod 30. Then, the second end of the rotating part 20 engages with the pressing part 10, and the teeth 221 of the ratchet 22 of the rotating part 20 engage in the gaps between adjacent wedge-shaped teeth 121 in the rotating groove 12 of the pressing part 10, locking them together. Finally, by rotating the rotating part 20, the pressing part 10 rotates in one direction and continuously pushes the push rod 30 axially, carrying the drug capsule towards the injection end in a linear motion.

[0068] In one example, alternatively, the plunger 30 may also include a locating key (not shown) disposed on the cylindrical surface of the plunger 30. During injection, the plunger 30 moves linearly along the axial direction, and the locating key engages with a locking structure inside the syringe 200 (e.g., Figure 6 When the locking structure 205 shown comes into contact with the push rod 30, the push stroke is completed and the movement stops.

[0069] In one example, such as Figure 4 and Figure 5 As shown, a protruding structure 24 is also provided on the cylindrical surface of the rotating part 20. The protruding structure 24 can provide frictional resistance during rotation, which facilitates rotation operation.

[0070] According to another aspect of the present invention, the following embodiment provides a syringe 200, wherein the triggering device 100 described in the above aspects is disposed at the pushing end of the syringe 200.

[0071] See Figure 6 The diagram illustrates the specific structure of a syringe 200 according to one embodiment. The syringe 200 includes a needle 202, a drug capsule 203, a delivery mechanism 204, a locking mechanism 205, and a triggering device 100, which are sequentially connected inside the syringe housing 201. The triggering device 100 is the same as described in the embodiments above, and is disposed at the delivery end of the syringe 200. The push rod 30 of the triggering device 100 is connected to the drug capsule 203 via the delivery mechanism 204 on the side away from the delivery end.

[0072] The specific structure and assembly method of the triggering device 100 can be combined with Figures 1-5 Referring to the descriptions of the embodiments above, further details will not be repeated here.

[0073] During the assembly of the syringe 200 and before its use, the pressing part 10 of the triggering device 100 is engaged and fixed together with the push rod 30, and a rotating part 20 is also sleeved between the pressing part 10 and the push rod 30. After the syringe 200 is assembled, the first end of the rotating part 20 engages with the push rod 30 through the first meshing tooth 21 and the second meshing tooth 32 to further fix the relative position of the push rod 30 within the syringe 200.

[0074] Before use, the syringe 200 is fixedly connected to the plunger 30 via the pressing part 10 and the rotating part 20, preventing the plunger 30 from rotating in the circumferential direction. Furthermore, even if the pressing part 10 is accidentally pressed, the rotating part 20 must be rotated to continue pushing the plunger 30, thus preventing the plunger 30 from moving and releasing the drug capsule before use, which would otherwise be wasteful.

[0075] When the syringe 200 is needed for injection, pressing the pressing part 10 triggers the engagement of the rotating part 20 and the push rod 30 to disengage. At the same time, the rotating part 20 is engaged with the pressing part 10, so that the push rod 30 will not rotate in the circumferential direction and will continue to be locked and fixed with the pressing part 10.

[0076] Next, the rotating part 20 is rotated, and the ratchet 22 at its second end engages with the wedge-shaped teeth 121 in the rotating groove 12 to rotate continuously in one direction (the rotation is irreversible) until the ratchet 22 is fully embedded in the bottom of the rotating groove 12. At the same time, under the pushing force of the pressing part 10, the push rod 30 continues to move linearly along the axial direction to push the drug capsule to realize the injection of the syringe 200.

[0077] The triggering device for a syringe and the syringe thereof provided by the embodiments of this utility model have at least one or a portion of the following advantages:

[0078] (1) By nesting the rotating part between the pressing part and the push rod, the syringe can be fixed to prevent the push rod from rotating circumferentially before use by connecting the first end of the rotating part to the push rod. When in use, the second end of the pressing part and the second end of the rotating part are nested together, so that the rotating part is disengaged from the push rod. The rotating part and the pressing part work together to rotate and push the push rod to move in a straight line along the circumferential direction.

[0079] (2) By cooperating with the limiting post of the pressing part and the limiting groove of the push rod, and by locking the locking key on the limiting post and the buckle on the limiting groove, the fixing between the pressing part and the push rod is strengthened, ensuring that the pressing part can be stably pushed to move linearly when the pressing part is pressed.

[0080] (3) By engaging the first meshing tooth of the rotating part with the second meshing tooth of the push rod, the push rod can be effectively fixed before the syringe is used to prevent it from rotating circumferentially, thereby reducing the assembly error or structural misalignment of the push rod in the syringe;

[0081] (4) By engaging the ratchet of the rotating part with the wedge-shaped teeth inside the rotating groove of the pressing part, the syringe can only rotate in one direction during use, avoiding reverse rotation;

[0082] (5) By setting a rotating part between the pressing part and the push rod, the push rod cannot be pushed even if the pressing part is pressed before the syringe is used, without rotating the rotating part, thereby avoiding accidental triggering before the syringe is used.

[0083] (6) By setting a sound device on the plunger, it can effectively prompt the plunger to push the drug capsule. At the same time, setting a positioning key on the plunger can effectively prompt the plunger in the syringe to complete the pushing stroke.

[0084] While some embodiments of the general concept of this utility model have been shown and described, those skilled in the art will understand that changes may be made to these embodiments without departing from the principles and spirit of the general concept of this utility model, the scope of which is defined by the claims and their equivalents.

Claims

1. A trigger device for a syringe, characterized in that, The triggering device includes: The pressing part is disposed at the push end of the syringe, and the pressing part includes a limiting post disposed along the axial direction and a rotating groove disposed along the circumferential direction; The rotating part is a centrally hollowed-out column and is sleeved on the limiting column. The rotating part includes a first meshing tooth arranged circumferentially at its first end and a ratchet arranged circumferentially at its second end. The push rod includes a limiting groove at the center of one end and a second meshing tooth arranged circumferentially thereon, the limiting groove abutting against the limiting post, and the other end of the push rod connecting to the drug capsule inside the syringe; wherein Before injection, the first meshing tooth and the second meshing tooth engage to fix the push rod so that it does not rotate circumferentially; During injection, after pressing the pressing part, the second meshing tooth disengages from the first meshing tooth and the ratchet is inserted into the rotating groove. Rotating the rotating part drives the pressing part to push the push rod to push the drug capsule axially.

2. The triggering device according to claim 1, characterized in that, At least one locking key is provided at the center of the limiting post of the pressing part; A buckle is provided at the center of the limiting groove of the push rod; The at least one snap-fit ​​key is engaged with the buckle to lock the pressing part and the push rod together.

3. The triggering device according to claim 2, characterized in that, At least two rib grooves are provided on the circumferential surface of the limiting post, and the grooving direction of each of the at least two rib grooves is parallel to the axial direction. At least two support ribs are provided in the limiting groove; Each of the at least two rib grooves is engaged with each of the at least two support ribs.

4. The triggering device according to claim 2, characterized in that, The rotating groove of the pressing part also includes wedge-shaped teeth, which are arranged one by one around the inside of the rotating groove in the same wedge angle direction along the circumference.

5. The triggering device according to claim 4, characterized in that, The ratchet of the rotating part includes teeth, and the shape of the tip of each tooth is matched with the gap shape of two adjacent wedge teeth; When injection is performed, after pressing the pressing part, the gear teeth engage in the gap between the adjacent wedge teeth, and rotating the rotating part causes the pressing part to rotate in a single direction.

6. The triggering device according to any one of claims 1-5, characterized in that, The first end of the rotating part also includes at least two ribs arranged circumferentially, the at least two ribs being inserted into the limiting groove of the push rod and abutting against at least two support ribs in the limiting groove.

7. The triggering device according to claim 6, characterized in that, The push rod also includes a positioning key, which is disposed on the cylindrical surface of the push rod; During injection, the plunger moves linearly along the axial direction. When the positioning key abuts against the locking structure inside the syringe, the plunger completes its pushing stroke and stops moving.

8. The triggering device according to claim 7, characterized in that, The cylindrical surface of the rotating part is also provided with a protruding structure.

9. The triggering device according to claim 8, characterized in that, The push rod further comprises a sounder for emitting a prompt sound during injection, the sounder being arranged at an end of the push rod abutting against the pressing part.

10. A syringe comprising, in succession, in its housing, a needle, a cartridge, a pushing mechanism, a blocking mechanism and a triggering device, characterized in that, The trigger device is according to any one of claims 1-9.

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