Needleless injector locking structure

Abstract

The utility model relates to a needleless injector locking structure belongs to needleless injector technical field, including upper shell, excitation button, button spring and locking assembly, locking assembly includes outer locking key, inner locking key, locking block and locking spring, inner locking key and locking block slide and fit, the eccentric hole is opened to locking block, the cylindrical surface of excitation button bottom and the hole site of eccentric hole, the edge of eccentric hole alternate corresponding when locking block moves along the radial direction of upper shell, realize the unlocking and locking of excitation button, locking spring sets up in the radial side of locking block, the utility model discloses when using need not synchronous operation locking and excitation, and the user can concentrate on aiming at injection site, significantly reduce the risk of misfire, improve injection accuracy, adopt the eccentric hole of locking block and the cylindrical surface of excitation button directly cooperate and limit excitation button stroke, compact structure is favorable to the control production cost, injection completion need not manual reset, convenient to use and continuously guarantee security.

Description

Technical Field

[0001] This utility model relates to a locking structure for a needleless injector, belonging to the technical field of needleless injectors. Background Technology

[0002] Needle-free injectors, based on Bernoulli's principle and the high-speed jet penetration effect, generate high pressure through mechanical power in a very short time, propelling the drug solution into an extremely fine micro-jet that penetrates the skin surface at high speed to directly enter the subcutaneous or muscle tissue. Compared with traditional needle injections, needle-free injections result in a diffused drug distribution, faster onset of action, higher absorption rate, less injection pain, and quicker operation, making them an ideal medical device to replace needle injections.

[0003] To prevent accidental activation of the trigger button and subsequent unintended injection of medication when not in use, needle-free injectors must be equipped with a locking device. Existing needle-free injectors typically employ a simultaneous locking mechanism, requiring both the locking button and the trigger button to be pressed simultaneously during injection. This method has significant drawbacks: firstly, simultaneous operation distracts the user, affecting accurate aiming at the injection site; secondly, hand misalignment during operation can easily lead to accidental triggering without proper skin alignment, resulting in medication waste, delayed treatment, and in severe cases, the high-pressure jet may even cause injury to the patient or user. Utility Model Content

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide a locking structure for a needleless injector, which realizes the step-by-step operation of unlocking and activation, supports pre-unlocking, and automatically locks after activation, greatly improving the safety and convenience of operation.

[0005] The needleless injector locking structure of this utility model includes an upper shell, an activation button, a button spring, and a locking assembly; the button spring is disposed in the internal cavity of the activation button, and the activation button is movably installed in the mounting position of the upper shell; the locking assembly includes an outer locking key, an inner locking key, a locking block, and a locking spring; The outer locking key and the inner locking key are fixedly connected and are respectively arranged on the outer and inner sides of the upper shell. The upper shell is provided with an axial sliding groove, and the outer locking key and the inner locking key can slide along the axial sliding groove. The inner locking key slides and fits into the locking block. When the inner locking key slides along the axial groove, it can push the locking block to move radially along the upper shell. When the inner locking key moves to the upper limit position of the axial groove, it can lock the position of the locking block. The locking block has an eccentric hole. When the locking block moves radially along the upper shell, the cylindrical surface at the bottom of the trigger button aligns alternately with the position of the eccentric hole and the edge of the eccentric hole, thereby unlocking and locking the trigger button. The locking spring is located on the radial side of the locking block and is used to apply an elastic restoring force in the locking direction to the locking block.

[0006] Furthermore, the inner locking key has a first inclined surface on the side facing the locking block, and the locking block has a corresponding second inclined surface. The first and second inclined surfaces are in contact with each other and can slide relative to each other. When the inner locking key moves to the upper limit position of the axial slide groove, the first and second inclined surfaces disengage from each other, the locking block contacts the flat end face of the inner locking key, and the position of the locking block is locked.

[0007] Furthermore, a small button is provided inside the trigger button. When the trigger button is pressed to the trigger position, the small button fills in the support of the steel ball to ensure smooth release of the hammer.

[0008] Furthermore, the structure also includes a hammer and an excitation spring. The side wall of the hammer is provided with a locking groove, and a steel ball is correspondingly provided inside the upper shell. When the hammer moves to the pressurized position, the steel ball is locked into the locking groove to achieve axial locking of the hammer. The excitation spring is sleeved on the outside of the hammer, with one end of the excitation spring abutting against the upper shell and the other end abutting against the bottom of the hammer.

[0009] Furthermore, the structure also includes a lower shell, and the upper shell and the lower shell are joined together to form a syringe housing. The upper shell and the lower shell can rotate relative to each other, and the hammer and the excitation spring are located inside the syringe housing.

[0010] The advantages of this utility model compared with the prior art are: 1. When using this utility model, first push the external locking key to unlock, then press the activation button to align with the injection site. There is no need to operate locking and activation simultaneously. Users can concentrate on aligning with the injection site, which significantly reduces the risk of accidental activation and improves injection accuracy. 2. The eccentric hole of the locking block directly matches the cylindrical surface of the trigger button to limit the travel of the trigger button. The structure is compact, the assembly is easy, and it is beneficial to control production costs. 3. After the injection is completed and the trigger button is released, the locking block will automatically spring back and lock under the action of the spring, without the need for manual reset, making it convenient to use and continuously ensuring safety. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model in the locked state; Figure 2 This is a structural diagram of the present invention in the unlocked state; Figure 3 This is a schematic diagram of the structure of this utility model in the excited state.

[0012] In the diagram: 1. Button spring; 2. Small button; 3. Steel ball; 4. Inner locking key; 401. First inclined surface; 5. Outer locking key; 6. Lower shell; 7. Upper shell; 8. Locking spring; 9. Locking block; 901. Eccentric hole; 902. Second inclined surface; 10. Hammer; 1001. Locking groove; 11. Actuation button; 12. Actuation spring. Detailed Implementation

[0013] The present invention will be further described below with reference to specific embodiments.

[0014] like Figure 1-3 As shown, this embodiment is achieved through the following technical solution: it includes an upper shell 7, an activation button 11, a button spring 1, and a locking assembly; the button spring 1 is disposed in the internal cavity of the activation button 11, and the activation button 11 is movably installed in the mounting position of the upper shell 7; the locking assembly includes an outer locking key 5, an inner locking key 4, a locking block 9, and a locking spring 8. The outer locking key 5 and the inner locking key 4 are fixedly connected and are respectively arranged on the outer and inner sides of the upper shell 7. The upper shell 7 is provided with an axial sliding groove, and the outer locking key 5 and the inner locking key 4 can slide along the axial sliding groove. The inner locking key 4 slides and engages with the locking block 9. When the inner locking key 4 slides along the axial groove, it can push the locking block 9 to move radially along the upper shell 7. When the inner locking key 4 moves to the upper limit position of the axial groove, it can lock the position of the locking block 9. The locking block 9 has an eccentric hole 901, the center of which does not coincide with the center of the locking block 9. When the locking block 9 moves radially along the upper shell 7, the cylindrical surface at the bottom of the trigger button 11 alternately corresponds with the hole position and edge of the eccentric hole 901, thereby unlocking and locking the trigger button 11. The locking spring 8 is located on the radial side of the locking block 9. One end of the locking spring 8 abuts against the inner wall of the upper shell 7, and the other end abuts against the locking block 9. It always applies a radially inward elastic force to the locking block 9, so that the locking block 9 maintains a locking tendency.

[0015] The inner locking key 4 has a first inclined surface 401 on the side facing the locking block 9, and the locking block 9 has a corresponding second inclined surface 902. The first inclined surface 401 and the second inclined surface 902 are in contact with each other and can slide relative to each other. When the inner locking key 4 moves to the upper limit position of the axial slide groove, the first inclined surface 401 and the second inclined surface 902 disengage from each other, and the locking block 9 contacts the flat end face of the inner locking key 4, thus locking the position of the locking block 9.

[0016] Inside the trigger button 11, there is also a small button 2. When the trigger button 11 is pressed to the trigger position, the small button 2 fills in the support of the steel ball 3 to ensure that the hammer 10 is released smoothly.

[0017] This structure also includes a hammer 10 and an excitation spring 12. The excitation spring 12 provides injection power to the hammer 10. A locking groove 1001 is provided on the side wall of the hammer 10, and a steel ball 3 is correspondingly provided inside the upper shell 7. When the hammer 10 moves to the pressurized position, the steel ball 3 is engaged in the locking groove 1001 to achieve axial locking of the hammer 10. The excitation spring 12 is sleeved on the outside of the hammer 10, with one end of the excitation spring 12 abutting against the upper shell 7 and the other end abutting against the bottom of the hammer 10. The ampoule is connected to the front end of the syringe housing. The ampoule contains a piston and a core rod, and the core rod is connected to the front end of the hammer 10.

[0018] The structure also includes a lower shell 6, an upper shell 7 and a lower shell 6 docking to form a syringe housing, the upper shell 7 and the lower shell 6 can rotate relative to each other, the hammer 10 and the excitation spring 12 are located inside the syringe housing, and the hammer 10 can slide inside the syringe housing.

[0019] The working principle of this utility model is as follows: 1. In the initial state, the outer locking key 5 is located at the lower end of the slide (near the injection end), and the locking block 9 is in a radially inward position under the elastic force of the locking spring 8. At this time, the eccentric hole 901 of the locking block 9 is misaligned with the cylindrical surface of the trigger button 11, and the edge of the eccentric hole 901 abuts against the front end of the cylindrical surface. The trigger button 11 cannot be pressed, and the syringe is in a locked state, effectively preventing accidental triggering caused by accidental contact.

[0020] 2. Rotating the lower shell 6 drives the hammer 10 to move backward via a threaded drive, compressing the excitation spring to store energy. When the locking groove 1001 of the hammer 10 aligns with the steel ball 3, the steel ball 3 is engaged in the locking groove 1001 under the radial force provided by the sloping rear wall of the locking groove, and the hammer 10 is axially locked, completing the pressurization. At this time, the excitation button 11 remains in the popped-out state under the action of the button spring 1, and its inner cylindrical surface blocks the outer side of the steel ball 3 to prevent the steel ball 3 from falling out, maintaining the locked state of the hammer 10; the locking assembly remains in the locked state, and the excitation button 11 cannot be pressed.

[0021] 3. After medication administration, push the outer locking key 5 upwards, causing the inner locking key 4 to slide axially along the groove. The inner locking key 4, through its inclined surface, pushes the locking block 9 to overcome the spring force of the locking spring 8, moving radially outwards. When the outer locking key 5 is pushed to the upper end of the groove, the eccentric hole 901 of the locking block 9 is completely aligned with the cylindrical surface of the activation button 11, and the activation button 11 receives a downward pressing stroke, completing the unlocking. At the same time, the flat end face of the inner locking key 4 contacts the flat end face of the locking block 9, preventing the locking block 9 from rebounding. At this time, the syringe is in the ready-to-activate state, and the user can release the outer locking key 5 and aim the injection tip at the patient's skin without continuously pressing the locking key.

[0022] 4. After aligning with the injection site, press the activation button 11. When the groove on the side wall of the activation button 11 corresponds to the position of the steel ball 3, it provides outward movement space for the steel ball 3. The radial force of the locking groove 1001 of the hammer 10 on the steel ball 3 causes the steel ball 3 to dislodge outward. The shear force between the hammer 10 and the steel ball 3 disappears. Under the elastic force of the activation spring 12, the hammer 10 quickly pops forward, pushing the piston and the liquid medicine in the ampoule, so that the liquid medicine is ejected at high speed from the micro-hole at the front end of the ampoule, completing the injection.

[0023] 5. During the activation process, the inner locking key 4 is pressed down by the activation button 11; after activation, the activation button 11 returns to its original position under the action of the button spring 1, leaving room for the locking block 9 to move. The locking block 9 rebounds under the action of the locking spring 8, and the cylindrical surface of the activation button 11 coincides with the edge of the eccentric hole 901, thus achieving locking.

Claims

1. A locking structure for a needleless injector, characterized in that, It includes an upper shell (7), an activation button (11), a button spring (1), and a locking assembly; the button spring (1) is disposed in the internal cavity of the activation button (11), and the activation button (11) is movably installed in the mounting position of the upper shell (7); The locking assembly includes an outer locking key (5), an inner locking key (4), a locking block (9), and a locking spring (8); the outer locking key (5) and the inner locking key (4) are fixedly connected and are respectively arranged on the outer side and the inner side of the upper shell (7). The upper shell (7) is provided with an axial groove, and the outer locking key (5) and the inner locking key (4) can slide along the axial groove. The inner locking key (4) slides against the locking block (9). When the inner locking key (4) slides along the axial groove, it can push the locking block (9) to move radially along the upper shell (7). When the inner locking key (4) moves to the upper limit position of the axial groove, it can lock the position of the locking block (9). The locking block (9) is provided with an eccentric hole (901). When the locking block (9) moves radially along the upper shell (7), the cylindrical surface at the bottom of the trigger button (11) and the hole position of the eccentric hole (901) and the edge of the eccentric hole (901) alternately correspond. The locking spring (8) is set on the radial side of the locking block (9).

2. The locking structure of the needleless injector according to claim 1, characterized in that, The inner locking key (4) has a first inclined surface (401) on the side facing the locking block (9), and the locking block (9) has a corresponding second inclined surface (902). The first inclined surface (401) and the second inclined surface (902) are in contact with each other and can slide relative to each other. When the inner locking key (4) moves to the upper limit position of the axial slide groove, the first inclined surface (401) and the second inclined surface (902) disengage from each other, and the locking block (9) contacts the flat end face of the inner locking key (4), thus locking the position of the locking block (9).

3. The locking structure of the needleless injector according to claim 2, characterized in that, A small button (2) is also provided inside the trigger button (11).

4. The locking structure of the needleless injector according to claim 3, characterized in that, It also includes a hammer (10) and an excitation spring (12). The side wall of the hammer (10) is provided with a locking groove (1001), and the upper shell (7) is provided with a steel ball (3). The excitation spring (12) is sleeved on the outside of the hammer (10). One end of the excitation spring (12) abuts against the upper shell (7), and the other end abuts against the bottom of the hammer (10).

5. The locking structure of the needleless injector according to claim 4, characterized in that, It also includes a lower shell (6), an upper shell (7) and a lower shell (6) docking to form a syringe housing, the upper shell (7) and the lower shell (6) can rotate relative to each other, and the hammer (10) and the excitation spring (12) are located inside the syringe housing.

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