Clutch injection structure of torsion spring automatic injector

Abstract

The clutch injection structure comprises a shell, a release button, a clutch cylinder, a small push rod, a large push rod, a torsion spring and a push rod driving piece, the push rod driving piece is installed in the shell, a first driving ratchet wheel is arranged on the push rod driving piece, the lower end of the large push rod is connected with the push rod driving piece, and a second driving ratchet wheel is arranged at the lower end of the large push rod. A first driving ratchet is arranged at the lower end of the large push rod, the push rod driving piece is in threaded connection with the small push rod, a second driving ratchet is arranged on the large push rod, a second driving ratchet is arranged at the lower end of the clutch cylinder, a gap is formed between the lower end of the clutch cylinder and the large push rod, and the torsion spring is connected with the shell and the clutch cylinder. The release button is connected with the clutch cylinder and can drive the lower end of the clutch cylinder to be connected with the large push rod. The design is simple in structure, convenient to produce and assemble and low in cost.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a torsion spring automatic syringe clutch injection structure. Background Art

[0002] Automatic syringes have reduced the difficulty of injection treatment and the pain of patients, and thus have been welcomed by many medical workers and patients. All automatic syringes include a reservoir, and the energy of the reservoir is released to assist the user in injecting a set dose of drug.

[0003] The invention patent with the authorized announcement number CN109996577B discloses a drug delivery device, including or adapted to receive a drug delivery device (1) filled with a cartridge, the drug delivery device including: a housing (50, 470), a piston rod (410) adapted to engage a piston (22) in a loaded cartridge (20) and axially displace it in the distal direction to thereby discharge a certain dose of drug from the cartridge, a transmission member (210, 211) defining a reference axis, a helical torsion drive spring (240) coupled to the transmission member and the housing and defining a spring axis coaxially arranged with the reference axis, the transmission member being arranged to rotate between an initial position and a full rotation position corresponding to the set maximum dose, whereby the drive spring is strained from an initial strained state to a fully strained state, a drive member (420, 421) engaging the piston rod and adapted to rotate through the transmission member to thereby

[0004] During the ejection, the piston rod is moved distally. A dose setting device (110, 160) that allows a user to simultaneously set the amount of a desired dose to be ejected and strain the drive spring accordingly by rotation of the transmission member. The dose setting device includes a dose setting member (110) that is rotatably coupled to the transmission member during dose setting and is adapted to rotate in a first direction to set the dose. A releasable ratchet mechanism (162, 222, 168, 179) that allows the dose setting member to rotate in the first direction to a set rotational position. A release device (161, 191, 254, 444) that is actuatable between a dose setting mode and an ejection mode. When the release device is actuated from the dose setting mode to the ejection mode, the ratchet mechanism is released. Wherein: The drive spring (240, 1240) includes a plurality of wire windings. The drive spring is at least partially formed of a wire having a rectangular cross-section (1243). The wire is wound vertically and has a height dimension and a thickness dimension, the height being greater than the thickness. Each portion of the wire having the rectangular cross-section has an initial non-strained inclination angle with respect to the normal of the spring axis. And when the drive spring is strained from the initial strained state to the fully strained state, the inclination angle of at least a portion of the wire having the rectangular cross-section will increase, which results in a corresponding non-linear spring characteristic. Its drive structure is relatively complex, causing trouble in production and assembly. SUMMARY OF THE INVENTION

[0005] An object of the present invention is to provide a clutch injection structure that is simple in structure and suitable for production and assembly in view of the deficiencies of the above-mentioned prior art.

[0006] The technical solution adopted by the present invention to solve its technical problems is as follows: a torsion spring automatic syringe clutch injection structure, which includes a housing, a release button, a clutch cylinder, a small push rod, a large push rod, a torsion spring and a push rod driving member. The push rod driving member is installed in the housing. A first driving ratchet is provided on the push rod driving member. The lower end of the large push rod is connected to the push rod driving member. A first driving ratchet tooth is provided at the lower end of the large push rod to cooperate with the first driving ratchet. The push rod driving member is threadedly connected to the small push rod. The lower end of the small push rod passes through the large push rod and the push rod driving member. A second driving ratchet tooth is provided on the large push rod. A second driving ratchet is provided at the lower end of the clutch cylinder to cooperate with the second driving ratchet tooth. There is a gap between the lower end of the clutch cylinder and the large push rod. One end of the torsion spring is connected to the housing, and the other end is connected to the clutch cylinder and can rotate synchronously with the clutch cylinder to accumulate or dissipate energy. The release button is connected to the upper end of the clutch cylinder and can drive the lower end of the clutch cylinder to be connected to the large push rod, so that the second driving ratchet and the second driving ratchet tooth are engaged. At this time, the stored energy of the torsion spring is released, driving the clutch cylinder to rotate. At this time, the clutch cylinder is already connected to the large push rod, driving the large push rod to rotate. The large push rod drives the small push rod to move spirally downward, and then pushes out and squeezes the medicine bottle to inject the medicine.

[0007] Further, the small push rod is provided with a driving external thread, and limiting grooves are provided on both sides of the small push rod. The push rod driving member is provided with an internal thread that cooperates with the driving external thread. A rib groove that cooperates with the limiting grooves is provided inside the large push rod. A push handle and a rubber stopper for conveniently squeezing the medicine bottle are connected to the lower end of the small push rod.

[0008] Further, a groove is provided on the upper end surface of the push rod driving member. The lower end of the large push rod extends into the groove. The first driving ratchet is arranged at the side wall of the groove. In this way, the assembly space of parts can be saved and the installation is convenient.

[0009] Further, a flexible ratchet arm is provided at the lower end of the large push rod. The first driving ratchet tooth is arranged on the outer end surface of the flexible ratchet arm. A cut-off surface is provided on the first driving ratchet tooth so that the large push rod can only rotate relative to the push rod driving member in one direction. In this way, when the first driving ratchet and the first driving ratchet tooth are engaged and rotated, the flexible ratchet arm keeps jumping on the ratchet surface, and a "clicking" injection reminder sound will be emitted.

[0010] Further, a positioning block or a positioning groove for cooperating with the housing to prevent the push rod driving member from rotating and facilitating installation is provided on the side wall of the push rod driving member.

[0011] Further, it further includes a memory member. The inner wall of the memory member is threadedly connected to the small push rod. The outer wall of the memory member is slidably connected to the inner wall of the clutch cylinder. The inner wall of the clutch cylinder is provided with a slide rail for cooperating with the memory member. The memory member is movably installed on the small push rod and can axially move on the small push rod. The lower end surface of the memory member is provided with an assembly portion that fits against the large push rod. The top of the small push rod is provided with a cut-off portion that cooperates with the upper end surface of the memory member. When setting the dose, the lower end surface of the memory member fits against the large push rod. The knob drives the clutch cylinder to rotate, and the clutch cylinder drives the memory member to spiral upward along the small push rod. During this process, the torsion spring stores energy. During this process, the clutch cylinder and the large push rod are in a non-engaged state. The knob is screwed clockwise to the required scale. When injecting, the clutch cylinder and the large push rod are engaged. After engagement, the stored energy of the torsion spring is released. When the torsion spring resets, it drives the large push rod to rotate counterclockwise. The large push rod drives the small push rod to spiral downward to push the push handle for injection, driving the memory member to reset to the assembly position of the large push rod. When the memory member contacts the large push rod, a "pop" injection completion prompt sound can be emitted. This process is repeated until the remaining drug amount is not enough for one dose. When adjusting the dose, the memory member reaches the cut-off position of the small push rod, and the dose cannot be increased further. The small push rod and the memory member are stuck to each other and cannot inject, completing the injection of the whole bottle of medicine.

[0012] Further, a guide rod is provided at the lower end of the release button. The guide rod extends into the upper end of the clutch cylinder. The release button is movably installed at the upper end of the clutch cylinder through the guide rod. An anti-detachment buckle that cooperates with each other is provided between the guide rod and the clutch cylinder.

[0013] Further, it further includes a release spring. The release spring connects the release button and the housing. The release spring keeps the clutch cylinder and the large push rod in a separated state.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This design has a simple structure, is convenient for production and assembly, and has a low cost. The clutch cylinder and the large push rod of this design adopt a clutch structure. When adjusting the dose, the clutch cylinder and the large push rod are separated, which is convenient for the torsion spring to accumulate energy. Pressing the release button to combine the clutch cylinder and the large push rod will release the injection, and a "click" prompt sound will be emitted during the injection process, indicating that the medicine is being injected until the injection is completed. This design can repeat the quantitative injection dose, and the effective stroke of the memory member limits the injection dose each time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Overall structural cross-sectional view of the present invention;

[0016] Figures 2 - 5 Schematic diagram of the clutch cylinder, push rod drive member, memory member and large push rod of the present invention;

[0017] Figure 6This is the assembly drawing of the small push rod structure of the present invention. Specific embodiments

[0018] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the following specific embodiments are only representative specific embodiments of the present invention. Among them, the specific methods, devices, conditions, materials, etc. exemplified are not used to limit the present invention or the corresponding specific embodiments.

[0019] In addition, the terms "lower", "lower end", and "lower part" in the text refer to the end towards the injection needle, and "upper", "upper end", and "upper part" refer to the opposite direction, that is, the end towards the release button.

[0020] A torsion spring automatic syringe clutch injection structure, as Figures 1 - 6 shown, which includes a housing 1, a release button 2, a clutch cylinder 3, a small push rod 4, a large push rod 5, a torsion spring 6, and a push rod driving member 7. The push rod driving member 7 is installed in the housing 1. A first driving ratchet 71 is provided on the push rod driving member 7. The lower end of the large push rod 5 is connected to the push rod driving member 7. A first driving ratchet tooth 51 that cooperates with the first driving ratchet 71 is provided at the lower end of the large push rod 5. The push rod driving member 7 is threadedly connected to the small push rod 4. The lower end of the small push rod 4 passes through the large push rod 5 and the push rod driving member 7. A second driving ratchet tooth 52 is provided on the large push rod 5. A connecting ratchet 31 is provided at the upper end of the clutch cylinder 3. A second driving ratchet 32 that cooperates with the second driving ratchet tooth 52 is provided at the lower end of the clutch cylinder 3. A gap is provided between the lower end of the clutch cylinder 3 and the large push rod 5. One end of the torsion spring 6 is connected to the housing 1, and the other end is connected to the clutch cylinder 3 and can rotate synchronously with the clutch cylinder 3 to accumulate or dissipate energy. The release button 2 is connected to the upper end of the clutch cylinder 3 and can drive the lower end of the clutch cylinder 3 to be connected to the large push rod 5, so that the second driving ratchet 32 and the second driving ratchet tooth 52 are engaged. At this time, the stored energy of the torsion spring 6 is released, driving the clutch cylinder 3 to rotate. At this time, the clutch cylinder 3 is already connected to the large push rod 5, driving the large push rod 5 to rotate. The large push rod 5 drives the small push rod 4 to move spirally downward, and then pushes and extrudes the medicine bottle to inject the medicine.

[0021] Furthermore, a driving external thread 41 is provided on the small push rod 4. Limiting grooves 42 are provided on both sides of the small push rod 4. An internal thread that cooperates with the driving external thread 41 is provided on the push rod driving member 7. A rib groove that cooperates with the limiting grooves 42 is provided inside the large push rod 5. A push handle and a rubber stopper for conveniently extruding the medicine bottle are connected to the lower end of the small push rod 4.

[0022] Further, a groove is provided on the upper end surface of the push rod driving member 7, the lower end of the large push rod 5 extends into the groove, and the first driving ratchet wheel 71 is arranged at the side wall of the groove, which can save the assembly space of parts and is convenient for installation.

[0023] Further, a flexible ratchet arm 53 is provided at the lower end of the large push rod 5, the first driving ratchet teeth 51 are arranged on the outer end surface of the flexible ratchet arm 53, and a cut-off surface is provided on the first driving ratchet teeth 51 so that the large push rod 5 can only rotate relative to the push rod driving member 7 in one direction. In this way, when the first driving ratchet wheel 71 and the first driving ratchet teeth 51 are engaged and rotated, the flexible ratchet arm 53 keeps jumping on the ratchet surface, and a "clicking" injection reminder sound will be emitted.

[0024] Further, a positioning block or positioning groove 72 is provided on the side wall of the push rod driving member 7 to cooperate with the housing 1 to prevent the push rod driving member 7 from rotating and is convenient for installation.

[0025] Further, a memory member 9 is further included. The inner wall of the memory member 9 is threadedly connected to the small push rod 4. A slider rib 91 is provided on the outer wall of the memory member 9. A slide rail is provided on the inner wall of the clutch cylinder 3 to cooperate with the slider rib 91. The outer wall of the memory member 9 is slidably connected to the inner wall of the clutch cylinder 3. The memory member 9 is movably installed on the small push rod 4 and can axially move and displace on the small push rod 4. An assembly portion that fits the large push rod 5 is provided on the lower end surface of the memory member 9. A cut-off portion 43 that cooperates with the upper end surface of the memory member 9 is provided at the top of the small push rod 4; when setting the dose, the lower end surface of the memory member 9 fits the large push rod 5, the knob drives the clutch cylinder 3 to rotate, the clutch cylinder 3 drives the memory member 9 to move spirally upward along the small push rod 4. During this process, the torsion spring 6 stores energy. During this process, the clutch cylinder 3 and the large push rod 5 are not engaged. The knob is screwed clockwise to the required scale; during injection, the clutch cylinder 3 and the large push rod 5 are engaged. After engagement, the stored energy of the torsion spring 6 is released. When the torsion spring 6 resets, it drives the large push rod 5 to rotate counterclockwise. The large push rod 5 drives the small push rod 4 to move spirally downward to push the push handle for injection, and drives the memory member 9 to reset to the assembly position of the large push rod 5. When the memory member 9 contacts the large push rod 5, a "pop" injection completion prompt sound can be emitted. Repeating this process multiple times for dose setting and injection, since the position of the memory member 9 on the small push rod 4 corresponds to the remaining drug amount, when the remaining drug amount is not enough for one dose, adjusting the dose increase will cause the memory member 9 to reach the cut-off portion of the small push rod 7, so that the dose cannot be increased any more, thereby preventing the adjustment of a dose exceeding the remaining drug amount.

[0026] Further, a guide rod is provided at the lower end of the release button 2. The guide rod extends into the upper end of the clutch cylinder 3. The release button 2 is installed at the upper end of the clutch cylinder 3 in a vertically movable manner through the guide rod. An anti-disengagement buckle that cooperates with each other is provided between the guide rod and the clutch cylinder 3.

[0027] Further, a release spring 8 is further included. The release spring 8 connects the release button 2 and the housing 1. The release spring 8 keeps the clutch cylinder 3 separated from the large push rod 5.

[0028] Further, a graduated cylinder 10 is further included. The inner wall of the graduated cylinder 10 is slidably connected to the outer wall of the clutch cylinder 3 up and down. A spiral slide rail is provided on the outer wall of the graduated cylinder 10. A clamping block that cooperates with the slide rail is provided on the inner wall of the housing 1. The outer wall of the graduated cylinder 10 is spirally slidably connected to the inner wall of the housing 1. In this way, when the clutch cylinder 3 drives the graduated cylinder 10 to rotate synchronously, the graduated cylinder 10 continuously rotates and moves up and down under the synchronous action of the outer wall and the inner wall, and the set injection volume can be accurately judged in cooperation with the window on the housing.

[0029] The above are only the preferred embodiments of the present invention, and the scope of implementation of the present invention cannot be limited thereby. That is, all simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the invention description still fall within the scope covered by the patent of the present invention.

Claims

1. A torsion spring automatic syringe clutch injection structure, comprising a housing, a release button, a clutch cylinder, a small push rod, a large push rod, a torsion spring and a push rod driving member, characterized in that: The push rod driving member is installed in the shell, and the push rod driving member is provided with a first driving ratchet. The lower end of the large push rod is connected to the push rod driving member, and the lower end of the large push rod is provided with a first driving ratchet that matches the first driving ratchet. The push rod driving member is threadedly connected to the small push rod, and the lower end of the small push rod passes through the large push rod and the push rod driving member. The large push rod is provided with a second driving ratchet, and the lower end of the clutch cylinder is provided with a second driving ratchet that matches the second driving ratchet. A gap is provided between the lower end of the clutch cylinder and the large push rod. One end of the torsion spring is connected to the shell, and the other end is connected to the clutch cylinder and can rotate synchronously with the clutch cylinder to accumulate or dissipate energy. The release button is connected to the upper end of the clutch cylinder and can drive the lower end of the clutch cylinder to connect with the large push rod, so that the second driving ratchet and the second driving ratchet are meshed.

2. The clutch injection structure of a torsion spring automatic syringe according to claim 1, characterized in that: The small push rod is provided with a driving external thread, and limiting grooves are provided on both sides of the small push rod. The push rod driving member is provided with an internal thread matching the driving external thread, and a rib groove matching the limiting groove is provided in the large push rod.

3. A torsion spring automatic syringe clutch injection structure according to claim 1 or 2, characterized in that: The lower end of the small push rod is connected with a push handle and a rubber plug.

4. The clutch injection structure of a torsion spring automatic syringe according to claim 1, characterized in that: The upper end surface of the push rod driving member is provided with a groove, the lower end of the large push rod extends into the groove, and the first driving ratchet is arranged on the side wall of the groove.

5. A torsion spring automatic syringe clutch injection structure according to claim 1 or 4, characterized in that: A flexible ratchet arm is provided at the lower end of the large push rod, and the first driving ratchet is arranged on the outer end surface of the flexible ratchet arm.

6. The clutch injection structure of a torsion spring automatic injector according to claim 1, characterized in that: It also includes a memory piece, the inner wall of the memory piece is threadedly connected to the small push rod, the outer wall of the memory piece is slidably connected to the inner wall of the clutch cylinder, the inner wall of the clutch cylinder is provided with a slide rail that cooperates with the memory piece, the memory piece is movably mounted on the small push rod and can move axially on the small push rod, the lower end face of the memory piece is provided with an assembly portion that fits the large push rod, and the top of the small push rod is provided with a cut-off portion that cooperates with the upper end face of the memory piece.

7. The clutch injection structure of a torsion spring automatic syringe according to claim 1, characterized in that: A guide rod is provided at the lower end of the release button, and the guide rod extends into the upper end of the clutch cylinder. The release button is mounted on the upper end of the clutch cylinder so as to be movable up and down through the guide rod. An anti-drop buckle that cooperates with each other is provided between the guide rod and the clutch cylinder.

8. A torsion spring automatic syringe clutch injection structure according to claim 1 or 7, characterized in that: A release spring is also included, wherein the release spring is connected to the release button and the housing, and the release spring keeps the clutch cylinder and the large push rod in a separated state.

9. The clutch injection structure of a torsion spring automatic syringe according to claim 1, characterized in that: A side wall of the push rod driving member is provided with a positioning block or a positioning groove which cooperates with the housing to prevent the push rod driving member from rotating.

Images