Torsion spring automatic injector

Abstract

The invention discloses a torsion spring automatic injector, comprising a pen body, the pen body is equipped with a dose setting component and an injection component; the injection component comprises a release button, a clutch cylinder, a small push rod, a torsion spring and a push rod driving member, the dose setting component comprises a knob, a clutch tooth and a jumping tooth, the upper end surface of the clutch tooth is provided with an inner ratchet ring, the knob is provided with an outer ratchet ring, the jumping tooth is movably installed in the knob, the lower end surface of the jumping tooth is provided with an inner tooth block and an outer tooth block respectively meshing with the inner ratchet ring and the outer ratchet ring, the knob is also provided with a plurality of rotating slots, the side of the jumping tooth is provided with a plurality of rotating blocks respectively inserted into the rotating slots, and the two ends of each rotating slot are respectively provided with a forward rotation rib block and a reverse rotation rib block for blocking the rotating block. The scheme has a simple structure, is easy to operate, is convenient to carry, and adopts axial jumping to adjust the dose and make sounds.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, in particular to an automatic injector. Background Art

[0002] Automatic injectors reduce the difficulty of injection therapy and the pain of patients, and are therefore welcomed by many medical workers and patients. Automatic injectors all include an energy accumulator, which helps users inject a set dose of medicine by releasing the energy of the energy accumulator.

[0003] In the prior art, the known winding pen syringe using a torsion spring is disclosed in the patent document with the publication number CN103249441B. The technical solution disclosed in the patent includes a housing for a syringe or a cartridge for containing a drug; a rotating drive shaft for rotating an adjustable predetermined amount to cause a corresponding amount of drug to be squeezed out from the syringe or cartridge; a torsion drive spring, which is fixed relative to the drive shaft at one end region and fixed to a joint at its other end region, and the joint is suitable for non-rotatably engaging the base on the housing. However, when adjusting the injection dose, if the user sets a dose greater than the expected dose, it is troublesome to reduce the set dose. Summary of the invention

[0004] The purpose of the present invention is to provide an automatic injector which can freely adjust the injection dose and adjust it more smoothly in view of the above-mentioned deficiencies in the prior art.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a torsion spring automatic injector, which includes a pen body, the pen body is equipped with a medicine bottle, an injection component and a dose setting component; the injection component includes a release button, a clutch cylinder, a small push rod, a torsion spring and a push rod driving member, and the dose setting component includes a knob, a clutch tooth and a jumping tooth; the knob is rotatably mounted on the upper end of the pen body, the upper end surface of the clutch tooth is provided with an inner ratchet ring, the knob is provided with an inner ring, the upper end surface of the inner ring is provided with an outer ratchet ring, and the The jumping tooth is movably installed in the knob, and the lower end surface of the jumping tooth is provided with an inner tooth block and an outer tooth block respectively meshing with the inner ratchet ring and the outer ratchet ring. The knob is also provided with a plurality of rotation slots, and the side of the jumping tooth is provided with a plurality of rotation blocks respectively inserted into the rotation slots. The rotation blocks can rotate a certain angle in the rotation slots, and the two ends of each rotation slot are respectively provided with a positive rotation rib block and a reverse rotation rib block for blocking the rotation block. When the jumping tooth is positioned at the first jumping tooth axial position, the inner The tooth block is fully meshed with the inner ratchet ring and the forward rotation rib block blocks the rotating block, the knob can drive the jumping tooth to rotate forward, the jumping tooth is connected to the clutch cylinder and drives the torsion spring to synchronously rotate forward to accumulate energy; when the jumping tooth is positioned at the second jumping tooth axial position, the inner tooth block is separated from the inner ratchet ring and the reverse rotation rib block blocks the rotating block, the torsion spring can drive the clutch cylinder and the jumping tooth to synchronously reverse to reduce energy; when the dose is set, the clutch cylinder is positioned at the first clutch cylinder axial position, The upper end of the clutch cylinder is connected to the beating tooth and can rotate synchronously with the beating tooth and the torsion spring; the release button is installed at the upper end of the clutch cylinder, and pressing the release button can push the clutch cylinder to be positioned in the second clutch cylinder axial position, and the upper end of the clutch cylinder is separated from the beating tooth and releases the torsion spring to drive the clutch cylinder to rotate, and when the clutch cylinder rotates, it drives the small push rod to rotate, and the push rod driving component converts the rotational torque of the small push rod into an axial propulsion force, thereby pushing out the squeezed medicine bottle for injection.

[0006] Furthermore, the forward rotating surfaces of the teeth of the outer ratchet ring, the inner ratchet ring, the inner tooth block and the outer tooth block are all inclined surfaces, and the reverse rotating surfaces are vertical surfaces. When the inner tooth block and the outer tooth block are fully meshed with the inner ratchet ring and the outer ratchet ring, the vertically arranged reverse rotating surfaces prevent the jumping teeth from freely reversing. When the knob rotates forward, the forward rotating rib block blocks the rotating block, the jumping teeth are in the first axial position of the jumping teeth, and the reverse rotating surface of the outer ratchet ring rotates toward the reverse rotating surface of the outer tooth block, so that the knob The jumping teeth are driven to rotate forward synchronously. During the forward rotation, since the forward rotating surfaces of the inner tooth block and the inner ratchet ring are meshed, the inner tooth block will fall into another tooth groove after finishing the meshing of one tooth block. The inner tooth block and the inner ratchet ring are repeatedly meshed, so that the jumping teeth will continuously jump at the tooth tip and tooth groove position of the inner ratchet ring. The meshing and collision of the inner tooth block and the inner ratchet ring will emit a loud "click" forward rotation reminder sound. During the forward rotation, the knob synchronously drives the jumping teeth and the clutch The cylinder and the torsion spring synchronously rotate forward to accumulate energy; when the knob is reversed, the reverse meshing of the outer ratchet ring and the forward rotating surface of the outer tooth block will cause the jumping tooth to move in the axial position, and the rotating block will rotate a certain angle in the rotating slot. When the reversing rib block blocks the rotating block, the meshing of the outer ratchet ring and the outer tooth block causes the jumping tooth to be positioned in the axial position of the second jumping tooth, the inner ratchet ring and the inner tooth block are separated, and the inner ratchet ring's ability to cut off the reverse surface of the inner tooth block fails. The clutch cylinder and the jumping tooth are reversed due to the torsion force of the torsion spring. When the rotating block reverses and hits the forward rotating rib block, the jumping tooth is restored to the axial position of the first jumping tooth. In this repeated reversal process, the jumping tooth jumps between the second jumping tooth axial position and the first jumping tooth axial position, and the end face collision of the jumping tooth and the clutch tooth will emit a loud "click" reversal reminder sound. During reversal, the torsion spring reduces energy to drive the clutch cylinder and the jumping tooth to reverse synchronously.

[0007] Furthermore, in order to make the structure more smoothly used, the outer ratchet ring and the inner ratchet ring are concentrically arranged, and the angle of rotation of the rotating block in the rotating slot is not greater than the angle of rotation of a single ratchet tooth of the inner ratchet ring (or outer ratchet ring), preferably 8° to 15°. The modules of the outer ratchet ring and the inner ratchet ring are the same, and the ratchet tooth height of the outer ratchet ring is greater than the ratchet tooth height of the inner ratchet ring, which is convenient for raising the jumping teeth, preferably the ratchet tooth height of the outer ratchet ring = 1.3mm, and the ratchet tooth height of the inner ratchet ring = 1mm.

[0008] Furthermore, the injection component also includes a release spring, which is arranged in the knob, and the two ends of the release spring respectively contact and connect the release button and the jumping tooth, so that the inner ratchet ring and the inner gear block remain engaged and the clutch cylinder is positioned at the first clutch cylinder axial position.

[0009] The release button is further provided with a guide rod at the lower end of the release button, and the guide rod extends into the upper end of the clutch cylinder, and the release button is movably mounted on the upper end of the clutch cylinder by the guide rod, and the upper end of the release button extends out of the upper end of the knob for easy pressing, and an anti-dropping buckle that cooperates with each other is provided between the guide rod and the clutch cylinder, and when the clutch cylinder is positioned in the first clutch cylinder axial position, the anti-dropping buckle between the guide rod and the clutch cylinder contacts and cooperates with each other, and a release gap is provided between the lower end surface of the release button and the upper end surface of the clutch cylinder, and the release button is pressed downward to make the release button move downward along the guide rod, and the anti-dropping buckle between the guide rod and the clutch cylinder is separated from each other, and the lower end surface of the release button can push the clutch cylinder to be positioned in the second clutch cylinder axial position after contacting the upper end surface of the clutch cylinder, and the release spring will push the release button to move upward after the release button is released, and the anti-dropping buckle between the guide rod and the clutch cylinder will drive the clutch cylinder to return to the first clutch cylinder axial position after contacting and cooperating with each other.

[0010] Further, the dose setting component also includes a graduated cylinder, the inner wall of the graduated cylinder is slidably connected to the outer wall of the clutch cylinder, and the outer wall of the graduated cylinder is spirally slidably connected to the inner wall of the pen body; wherein the inner wall of the graduated cylinder and the outer wall of the clutch cylinder are provided with a plurality of guide rails and sliders that cooperate with each other, and the guide rails and sliders are evenly distributed on the inner wall of the graduated cylinder and the outer wall of the clutch cylinder in a circumferential manner. The clutch teeth and / or the pen body are provided with zero position limiting ribs and end position limiting ribs that cooperate with the graduated cylinder.

[0011] Furthermore, considering that some medicine bottles have a large dosage and can be injected multiple times, the injection component of the present design also includes a large push rod, the push rod drive component is installed in the pen body, and the side wall of the push rod drive component is provided with a positioning block or a positioning groove that cooperates with the pen body to prevent the push rod drive component from rotating and facilitates installation. The push rod drive component is provided with a first driving ratchet, and the lower end of the large push rod is provided with a first driving ratchet that cooperates with the first driving ratchet. The small push rod is provided with a driving external thread, and the push rod drive component is provided with a driving internal thread that cooperates with the small push rod. The push rod drive component is threadedly connected with the small push rod, and the lower end of the small push rod passes through the large push rod and the push rod drive component and is connected with a push handle and a rubber plug that are convenient for squeezing the medicine bottle. The large push rod is provided with a rib groove that cooperates with the small push rod, and the large push rod is provided with a second driving ratchet. The lower end of the clutch cylinder is provided with a second driving ratchet. When setting the dose, the clutch cylinder is positioned at the axial position of the first clutch cylinder, and a gap of about 0.2 mm is provided between the lower end of the clutch cylinder and the large push rod. The second driving ratchet and the second driving ratchet are not engaged. At this time, when the knob rotates forward and reversely, the forward and reverse rotation of the clutch cylinder is independent, and the torsion spring can accumulate energy with the forward rotation of the clutch cylinder at this time; during injection, the clutch cylinder is positioned at the axial position of the second clutch cylinder, and the lower end of the clutch cylinder is connected to the large push rod, and the second driving ratchet and the second driving ratchet are engaged. The stored force of the torsion spring is released, driving the clutch cylinder to rotate counterclockwise. At this time, the clutch cylinder is connected to the large push rod, driving the large push rod to rotate counterclockwise, and the rib groove in the large push rod drives the small push rod to spiral downward counterclockwise, transmitting the force to the push handle, and pushing the rubber plug downward for injection. After the injection is completed, the clutch cylinder is restored to the axial position of the first clutch cylinder, and the clutch cylinder is separated from the large push rod. Among them, a flexible ratchet arm is provided at the lower end of the large push rod, and the first drive ratchet is arranged on the outer end surface of the flexible ratchet arm. A cut-off surface is provided on the first drive ratchet so that the large push rod can only rotate in one direction (counterclockwise) relative to the push rod driving member. In this way, when the first drive ratchet and the first drive ratchet are engaged and rotated, the flexible ratchet arm keeps jumping on the ratchet surface, and a "click" injection reminder sound will be emitted.

[0012] Furthermore, the injection component 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 undergo axial displacement 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 fits with the upper end face of the memory piece; when the dose is set, the clutch cylinder is positioned at the first axial position of the clutch cylinder, the lower end face of the memory piece fits the large push rod, the knob drives the jumping tooth and the clutch cylinder to rotate clockwise, and the clutch cylinder drives the memory piece to move upward along the spiral of the small push rod. In this process, the torsion spring stores force, and this During the process, the clutch cylinder and the large push rod are in a non-engaged state, and the knob is turned clockwise to the required scale; when injecting, press the top cap downward to release the torsion spring. During the downward pressing process, the clutch cylinder engages with the large push rod. After engagement, the clutch cylinder separates from the jumping tooth, releasing the force stored in the torsion spring. When the torsion spring is reset, it drives the large push rod to rotate counterclockwise, and the large push rod drives the small push rod to spiral downward, push the push handle to inject, and drive the memory piece to reset to the large push rod assembly. The moment the memory piece contacts the large push rod, a "pop" injection completion prompt sound is emitted, and this cycle repeats until the remaining amount of medicine is less than one dose. When adjusting the dose, the memory piece reaches the end point of the small push rod, and the adjusted dose can no longer be increased. The small push rod and the memory piece are stuck with each other and cannot be injected, completing the injection of the entire bottle of medicine. At this time, the knob can no longer be rotated.

[0013] Furthermore, the upper end of the clutch cylinder is connected to the jumping tooth by a ratchet or key connection to achieve synchronous rotation, and the clutch cylinder and the jumping tooth can move axially up and down to achieve separation.

[0014] Furthermore, the pen body includes an upper pen body and a lower pen body connected to each other, the lower pen body includes a refill frame and a pen cap, a cartridge medicine bottle is installed in the refill frame, the upper end of the refill frame is snap-connected or threadedly connected to the upper pen body, and the pen cap is detachably mounted on the refill frame. A pen clip is also provided on the pen cap for easy carrying.

[0015] Furthermore, the outer surface of the knob is provided with concave and convex patterns for easy twisting.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: the torsion spring automatic injector of the present design has a simple structure, is easy to operate, and is convenient to carry. The injection using the torsion spring as the driving force improves the convenience and comfort of medication, and can complete the injection process quickly and stably. Its dose setting component adopts a knob, a clutch tooth, and a jumping tooth. The desired dose is adjusted by rotating the knob forward and reverse. Since the elastic force of the torsion spring is stable and controllable, the dose adjustment mechanism can achieve high-precision dose setting, thereby ensuring the accuracy of the injection dose. In addition, the elastic characteristics of the torsion spring make the injection pen more stable during use, reducing the injection deviation caused by external force interference. The elastic characteristics of the torsion spring also enable the dose adjustment mechanism to automatically reset after use, thereby improving the reliability and service life of the injection pen. The axial jump of the jumping tooth during the forward and reverse rotation process will emit a prompt sound during the adjustment process, which is convenient for users to use. The clutch cylinder, large push rod and push rod driving component of its injection component adopt internal gear clutch. When not released, the clutch cylinder and the large push rod are not engaged, which does not affect the screwing operation when setting the dose. The combination of the large push rod, the memory component and the push rod driving component enables the syringe to be injected multiple times to complete the injection of the entire bottle of medicine, and a prompt sound can also be issued during the injection process, which is convenient for users. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an exploded view of the overall structure of the present invention;

[0018] Figure 2 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 3 and Figure 4 It is a cross-sectional view of the structure of the present invention;

[0020] Figure 5 It is an assembly diagram of the jumping tooth structure of the present invention;

[0021] Figure 6 and Figure 7 It is a cross-sectional view of the assembly of the jumping tooth structure of the present invention;

[0022] Figure 8 It is the assembly diagram of the small push rod structure of the present invention;

[0023] Fig. 9 and Fig.10 It is the assembly diagram of the scale cylinder structure of the present invention;

[0024] Fig.11 A cross-sectional view of the upper pen body structure of the present invention;

[0025] Fig.12 It is a structural assembly diagram of the push rod driving member of the present invention;

[0026] Figure 13-15 They are schematic diagrams of the push rod driving member, the memory member and the large push rod structure of the present invention;

[0027] Figure 16-18 They are schematic diagrams of the knob, clutch tooth and jumping tooth structures of the present invention respectively. DETAILED DESCRIPTION

[0028] The present invention is 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, wherein the specific methods, devices, conditions, materials, etc. cited are not intended to limit the present invention or the corresponding specific embodiments.

[0029] In addition, the terms "lower", "lower end" and "lower part" herein refer to the end toward the injection needle, and "upper", "upper end" and "upper part" refer to the opposite direction, that is, the end toward the release button.

[0030] A torsion spring automatic injector, such as Figures 1 to 18 As shown, it includes a pen body, which is composed of an upper pen body 11 and a lower pen body connected to each other. The lower pen body includes a pen core frame 12 and a pen cap 13. A card-type medicine bottle 14 is installed in the pen core frame 12. The upper end of the pen core frame 12 is snap-connected or threaded with the upper pen body 11. The lower end of the pen core frame 12 is provided with a connecting thread for connecting an injection needle. The pen cap 13 is detachably sleeved on the pen core frame 12. The pen core frame 12 and the pen cap 13 can be provided with mutually matching elastic buckles for positioning. The upper pen body 11 is equipped with an injection component and a dose setting component.

[0031] The injection member includes a release button 21, a clutch cylinder 22, a small push rod 23, a torsion spring 24, a push rod driver 25, a release spring 26, a large push rod 27 and a memory element 28. The dose setting member includes a knob 31, a clutch tooth 32 and a jumping tooth 33.

[0032] The knob 31 is rotatably mounted on the upper end of the upper pen body 11, and the upper end surface of the clutch tooth 32 is provided with an inner ratchet ring 321. The clutch tooth 32 is clamped in the upper pen body 11 and cannot rotate. A positioning buckle that cooperates with the upper pen body 11 is provided. An inner ring is provided inside the knob 31, and an outer ratchet ring 311 is provided on the upper end surface of the inner ring. The jumping tooth 33 is movably installed in the knob 31, and the lower end surface of the jumping tooth 33 is provided with an inner tooth block 332 and an outer tooth block 331 respectively meshing with the inner ratchet ring 321 and the outer ratchet ring 311. The knob 31 is also provided with a plurality of rotation slots, and the side edges of the jumping tooth 33 are provided with a plurality of rotation blocks 333 respectively inserted into the rotation slots. The rotation blocks can rotate a certain angle in the rotation slots, and the two ends of each rotation slot are respectively provided with a forward rotation rib block 312 and a reverse rotation rib block 313 for blocking the rotation block 333. The upper end of the clutch cylinder 22 passes through the clutch tooth 32 and the inner ring. The upper end of the clutch cylinder 22 is connected to the jumping tooth 33 by a ratchet (in other embodiments, a key connection can also be used) to achieve synchronous rotation. The jumping tooth 33 is provided with an inner ratchet 330 that cooperates with the clutch cylinder 22. The clutch cylinder 22 and the jumping tooth 33 can move axially up and down to achieve separation. The lower end of the release button 21 is provided with a guide rod 211, and the guide rod 211 extends into the upper end of the clutch cylinder 22. The release button 21 is installed on the upper end of the clutch cylinder 22 by the guide rod 211, and the upper end of the release button 21 extends out of the upper end of the knob 31 for easy pressing. The guide rod 211 and the clutch cylinder 22 are provided with anti-drop buckles that cooperate with each other. The release spring 26 is arranged in the knob 31, and the two ends of the release spring 26 are respectively in contact with the release button 21 and the jumping tooth 33. The release spring 31 provides a spring force to keep the jumping tooth 33 in contact with the clutch tooth 32, so that the inner tooth block 332 and the outer tooth block 331 are kept in meshing with the inner ratchet ring 321 and the outer ratchet ring 311, so that the jumping tooth 33 is positioned in the first jumping tooth axial position and the clutch cylinder 22 is positioned in the first clutch cylinder axial position.

[0033] The push rod driving member 25 is installed in the lower end of the upper pen body 11, and the side wall of the push rod driving member 25 is provided with a positioning block or positioning groove 251 that cooperates with the upper pen body 11 to prevent the push rod driving member 25 from rotating and facilitates installation. A groove is provided in the middle of the push rod driving member 25, and a first driving ratchet 252 is provided on the inner wall of the groove. The lower end of the large push rod 27 is supported on the end surface of the groove, and the lower end supporting side wall of the large push rod 27 is provided with a first driving ratchet 271 that cooperates with the first driving ratchet 252. The small push rod 23 is provided with a driving external thread, and the push rod driving member 25 is provided with a driving internal thread that cooperates with the small push rod 23. The push rod driving member 25 is threadedly connected with the small push rod 23, and the lower end of the small push rod 23 passes through the large push rod 27 and the push rod driving member 25 and is connected with a push handle and a rubber plug for conveniently squeezing the medicine bottle 14. A rib groove 272 that cooperates with the small push rod 23 is provided in the large push rod 27, and a second driving ratchet 273 is also provided on the large push rod 27. The lower end of the clutch cylinder 22 is provided with a second driving ratchet 221 that cooperates with the second driving ratchet 273. The inner wall of the memory element 28 is threadedly connected to the small push rod 23, and the outer wall of the memory element 28 is slidably connected to the inner wall of the clutch cylinder 22. The outer wall of the memory element 28 is provided with a slider rib 281.

[0034] The inner wall of the clutch cylinder 22 is provided with a slide rail that matches the slider rib 281. The memory piece 28 is movably installed on the small push rod 23. The lower end surface of the memory piece 28 is provided with an assembly portion that fits the large push rod 27. The top of the small push rod 23 is provided with a cut-off portion that matches the upper end surface of the memory piece 28.

[0035] like Figure 3 and Figure 4As shown, when setting the dose, the clutch cylinder 22 is positioned at the first clutch cylinder axial position, the anti-drop buckle between the guide rod 211 and the clutch cylinder 22 is in contact with each other, and a release gap is provided between the lower end surface of the release button 21 and the upper end surface of the clutch cylinder 22. A gap of about 0.2 mm is provided between the lower end of the clutch cylinder 22 and the large push rod 27, and the second drive ratchet 221 and the second drive ratchet 273 are not engaged. At this time, when the knob 31 rotates forward and reverse, the forward and reverse rotation of the clutch cylinder 22 is independent, and the torsion spring can accumulate energy with the forward rotation of the clutch cylinder 22; at this time, the lower end surface of the memory element 28 is in contact with the upper end surface of the large push rod 27. When the jumping tooth 33 is positioned at the first jumping tooth axial position, the inner tooth block 332 is fully engaged with the inner ratchet ring 321 and the forward rotation rib block 312 blocks the rotation block 333. When the knob 31 drives the jumping tooth 33 to rotate forward through the forward rotation rib block 312, the upper end of the clutch cylinder 22 is connected to the jumping tooth 33 and can rotate synchronously with the jumping tooth 33 and the torsion spring 24. The clutch cylinder 22 drives the memory piece 28 to move upward along the small push rod 23. In this process, the torsion spring 24 accumulates energy. When the jumping tooth 33 is positioned at the second jumping tooth axial position, the inner tooth block 332 is separated from the inner ratchet ring 321 and the reverse rib block 33 blocks the rotation block 333. Since the limiting effect of the inner ratchet ring 321 on the inner tooth block 332 disappears, the accumulated capacity of the torsion spring 34 can actively drive the clutch cylinder 22 and the jumping tooth 33 to reverse synchronously to reduce energy. When the clutch cylinder 22 rotates, it will also drive the memory piece 28 to move downward along the small push rod 23.

[0036] The release button 21 is pressed and moved downward along the guide rod 211, and the anti-detachment buckles between the guide rod 211 and the clutch cylinder 22 are separated from each other. After the lower end surface of the release button 21 contacts the upper end surface of the clutch cylinder 22, the clutch cylinder 22 can be pushed to be positioned in the axial position of the second clutch cylinder. The upper end of the clutch cylinder 22 is separated from the jumping tooth 33, and the lower end of the clutch cylinder 22 is connected to the large push rod 27. The second drive ratchet and the second drive ratchet are engaged. At this time, the stored force of the torsion spring 24 is released, driving the clutch cylinder 22 to rotate counterclockwise. The clutch cylinder is now connected to the large push rod 27, driving the large push rod 27 to rotate counterclockwise, and the rib groove in the large push rod 27 drives the small push rod 23 to move downward in a counterclockwise spiral, transmitting the force to the push handle 25, pushing the rubber stopper downward for injection, and then pushing out the squeezed medicine bottle for injection. When the small push rod 23 moves counterclockwise and spirally downward, it drives the memory element 28 to return to the assembly position of the large push rod 27. When the memory element 28 contacts the large push rod 27, a "pop" sound indicating that the injection is completed can be emitted.

[0037] After the injection is completed, the release button 21 is released. Due to the effect of the release spring 26, the anti-drop buckle between the guide rod 211 and the clutch cylinder 22 contacts and cooperates with each other, which will drive the clutch cylinder 22 to resume positioning at the first clutch cylinder axial position. Except that the position of the small push rod 23 at the push rod driving member 25 is maintained in the post-injection state, the other parts are all restored to the dose setting state. In this way, the dose setting and injection are repeated many times. Since the position of the memory member 28 at the small push rod 23 corresponds to the remaining amount of medicine, when the remaining amount of medicine is not enough for one dose, the increase in the adjusted dose will cause the memory member 28 to reach the cut-off portion of the small push rod 23, so that the dose can no longer be increased. At this time, the knob 31 can no longer be rotated, so as to prevent the dose from being adjusted to exceed the remaining amount of medicine.

[0038] Further, such as Figures 5 to 7 As shown, the positive rotation surfaces of the teeth of the outer ratchet ring 311, the inner ratchet ring 321, the inner tooth block 331 and the outer tooth block 332 are all inclined surfaces, and the reverse rotation surfaces are all vertical surfaces. When the inner tooth block 331 and the outer tooth block 332 are fully meshed with the inner ratchet ring 321 and the outer ratchet ring 311, the vertically arranged reverse rotation surfaces prevent the jumping tooth 33 from freely reverse rotation even if it is subjected to the reverse torsion force accumulated by the torsion spring 24 on the clutch cylinder 22. Figure 6 As shown, when the knob 31 rotates forward, the forward rotation rib block 312 blocks the rotating block 333, the jumping tooth 33 is at the first jumping tooth axial position, and the reverse rotation surface of the outer ratchet ring 311 faces the reverse rotation surface of the outer tooth block 331, so that the knob 31 can drive the jumping tooth 33 to rotate forward synchronously. During the forward rotation, since the inner tooth block 332 and the forward rotation surface of the inner ratchet ring 321 are meshed, the inner tooth block 332 ends the meshing of one tooth block. After the inner tooth block 332 is engaged, it will fall into another tooth groove. The inner tooth block 332 and the inner ratchet ring 321 are repeatedly engaged, so that the jumping tooth 33 will jump continuously at the tooth tip and tooth groove position of the inner ratchet ring 321. The meshing and collision of the inner tooth block 332 and the inner ratchet ring 321 will produce a loud "click" forward rotation reminder sound. When the knob 31 is in forward rotation, it will synchronously drive the jumping tooth 33, the clutch cylinder 22 and the torsion spring 24 to synchronously rotate forward to accumulate energy. Figure 7As shown, when the knob 31 is reversed, the outer ratchet ring 311 actively engages with the positive rotation surface of the outer tooth block 331 in a reverse manner. Due to the inclined setting of the positive rotation surface, the jumping tooth 33 moves in the axial position, and the rotating block 333 can rotate a certain angle in the rotating slot. When the reversing rib block 313 blocks the rotating block 333, the jumping tooth 33 is positioned at the second axial position of the jumping tooth, and the inner ratchet ring 321 and the inner tooth block 332 are separated. The inner ratchet ring 321 loses its ability to cut off the reverse surface of the inner tooth block 332. The clutch cylinder 22 and the jumping tooth 33 are reversed due to the torsion of the torsion spring 24, and the rotating block 333 reverses and hits the positive rotation surface. When the rib block 312 is moved, the spring 26 is released and the jumping tooth 33 is restored to the first jumping tooth axial position. The inner tooth block 332 re-engages with the inner ratchet ring 321. The above action is repeated during the reversal of the knob 31. The jumping tooth 33 jumps between the second jumping tooth axial position and the first jumping tooth axial position. The rotating block 333 also rotates and slides back and forth in the slot. The meshing surface of the jumping tooth 33 and the clutch tooth 32 (the meshing surface of the inner tooth block 332 and the inner ratchet ring 321) collides and emits a loud "click" reversal reminder sound. During reversal, the torsion spring 24 dissipates energy to drive the clutch cylinder 22 and the jumping tooth 33 to reverse synchronously.

[0039] Furthermore, in order to make the structure more smoothly used, the outer ratchet ring 311 and the inner ratchet ring 321 are concentrically arranged, and the angle of rotation of the rotating block 333 in the rotating slot is not greater than the angle of rotation of a single ratchet tooth of the inner ratchet ring 311 (or the outer ratchet ring 321), preferably 10°. The outer ratchet ring 311 and the inner ratchet ring 321 have the same module, and the ratchet tooth height of the outer ratchet ring 311 is greater than the ratchet tooth height of the inner ratchet ring 321, which is convenient for raising the jumping tooth 33, preferably the ratchet tooth height of the outer ratchet ring 311 = 1.3mm, and the ratchet tooth height of the inner ratchet ring 321 = 1mm, so that the jumping tooth 33 can be stably raised until the inner ratchet ring 321 is separated from the inner tooth block 332.

[0040] Further, such as Figure 9-11As shown, the dose setting component also includes a graduated cylinder 34, the inner wall of which is slidably connected to the outer wall of the clutch cylinder 22, the outer wall of which is provided with a spiral slide rail 341, the inner wall of the upper pen body 11 is provided with a block 111 that cooperates with the slide rail 341, and the outer wall of the graduated cylinder 34 is spirally slidably connected to the inner wall of the upper pen body, so that when the clutch cylinder 22 drives the graduated cylinder 34 to rotate synchronously, the graduated cylinder 34 is continuously rotated and moved 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 upper pen body 11. Among them, the inner wall of the graduated cylinder 34 and the outer wall of the clutch cylinder 22 are provided with a plurality of mutually cooperating guide rails 220 and sliders, and the guide rails 220 and sliders are evenly arranged on the inner wall of the graduated cylinder 34 and the outer wall of the clutch cylinder 22 in a circumferential manner. The clutch tooth 32 is provided with a zero position limiting rib 221 that cooperates with the scale barrel 34 , and the upper pen body 11 is provided with a termination limiting rib that cooperates with the scale barrel 34 .

[0041] Furthermore, a flexible ratchet arm 274 is provided at the lower end of the large push rod 27, and the first drive ratchet 271 is arranged on the outer end surface of the flexible ratchet arm 274. A cut-off surface is provided on the first drive ratchet 271 so that the large push rod can only rotate in one direction (counterclockwise) relative to the push rod driving member 25. In this way, when the first drive ratchet 252 and the first drive ratchet 271 engage and rotate, the flexible ratchet arm 274 keeps jumping on the ratchet surface, and a "click" injection reminder sound will be emitted.

[0042] Furthermore, the pen cap 13 is also provided with a pen clip for easy carrying.

[0043] Furthermore, the outer surface of the knob 31 is provided with concave-convex patterns for easy twisting.

[0044] This embodiment has a simple structure, is easy to produce and install, and is easy to operate and carry. Its overall structure is compact and scientific, and its movement is smooth. Using a torsion spring as a driving force for injection improves the convenience and comfort of medication, and can quickly and stably complete the injection process, which is suitable for promotion and application. Its dose setting component uses a knob, a clutch tooth and a jumping tooth. The desired dose is adjusted by rotating the knob forward and reverse. Since the elastic force of the torsion spring is stable and controllable, the dose adjustment mechanism can achieve high-precision dose setting, thereby ensuring the accuracy of the injection dose. In addition, the elastic characteristics of the torsion spring make the injection pen more stable during use, reducing the injection deviation caused by external force interference. The elastic characteristics of the torsion spring also enable the dose adjustment mechanism to automatically reset after use, improving the reliability and service life of the injection pen. The axial jump of the jumping tooth during the forward and reverse rotation process will emit a prompt sound during the adjustment process, which is convenient for users to use. The clutch cylinder, large push rod and push rod driving component of its injection component adopt internal gear clutch. When not released, the clutch cylinder and the large push rod are not engaged, which does not affect the screwing operation when setting the dose. The combination of the large push rod, the memory component and the push rod driving component enables the syringe to be injected multiple times to complete the injection of the entire bottle of medicine, and a prompt sound can also be issued during the injection process, which is convenient for users.

[0045] The above description is only a preferred embodiment of the present invention, and it cannot be used to limit the scope of the present invention. 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 are still within the scope of the patent of the present invention.

Claims

1. A torsion spring automatic injector, comprising a pen body, wherein the pen body is equipped with a dose setting component and an injection component; characterized in that: The injection component comprises a release button, a clutch cylinder, a small push rod, a torsion spring and a push rod driving member, and the dose setting component comprises a knob, a clutch tooth and a jumping tooth; the knob is rotatably mounted on the upper end of the pen body, the upper end surface of the clutch tooth is provided with an inner ratchet ring, the knob is provided with an inner ring, the upper end surface of the inner ring is provided with an outer ratchet ring, the jumping tooth is mounted in the knob, the lower end surface of the jumping tooth is provided with an inner tooth block and an outer tooth block respectively meshing with the inner ratchet ring and the outer ratchet ring, a plurality of rotation slots are also provided in the knob, a plurality of rotation blocks respectively inserted into the rotation slots are provided on the side of the jumping tooth, and a positive rotation rib block and a reverse rotation rib block respectively blocking the rotation block are provided at both ends of each of the rotation slots; when the jumping tooth is positioned at the first axial position of the jumping tooth, the inner tooth block is fully meshed with the inner ratchet ring and the positive rotation rib block blocks the rotation block, and the knob can drive the jumping tooth. The teeth rotate forward, and the jumping tooth is connected to the clutch cylinder and drives the torsion spring to rotate forward synchronously to accumulate energy; when the jumping tooth is positioned at the axial position of the second jumping tooth, the inner tooth block is separated from the inner ratchet ring and the reversing rib block blocks the rotating block, and the torsion spring can drive the clutch cylinder and the jumping tooth to synchronously reverse and reduce energy; when the dose is set, the clutch cylinder is positioned at the axial position of the first clutch cylinder, and the upper end of the clutch cylinder is connected to the jumping tooth and can rotate synchronously with the jumping tooth and the torsion spring; the release button is installed at the upper end of the clutch cylinder, and pressing the release button can push the clutch cylinder to be positioned at the axial position of the second clutch cylinder, and the upper end of the clutch cylinder is separated from the jumping tooth and releases the torsion spring to drive the clutch cylinder to rotate, and when the clutch cylinder rotates, it drives the small push rod to rotate, and the push rod driving member converts the rotational torque of the small push rod into an axial propulsion force, thereby pushing out the squeezed medicine bottle for injection.

2. A torsion spring automatic injector according to claim 1, characterized in that: The forward rotation surfaces of the tooth shapes of the outer ratchet ring, the inner ratchet ring, the inner tooth block and the outer tooth block are all inclined surfaces, and the reverse rotation surfaces are vertical surfaces; when the knob rotates forward, the forward rotation rib block blocks the rotating block to drive the jumping tooth to rotate. During the forward rotation process, the meshing and collision of the inner tooth block and the inner ratchet ring will emit a forward rotation reminder sound; when the knob is reversed, the outer ratchet ring and the outer tooth block are reversely meshed to make the jumping tooth move in the axial position. When the reverse rib block blocks the rotating block, the jumping tooth is positioned at the second jumping tooth axial position, the inner ratchet ring and the inner tooth block are separated, the clutch cylinder and the jumping tooth are reversed due to the torsion of the torsion spring, and when the rotating block reverses and hits the forward rotation rib block, the jumping tooth is restored to the first jumping tooth axial position. In this repeated reversal process, the jumping tooth jumps between the second jumping tooth axial position and the first jumping tooth axial position, and the end face collision of the jumping tooth and the clutch tooth will emit a reverse reminder sound.

3. A torsion spring automatic injector according to claim 2, characterized in that: The outer ratchet ring and the inner ratchet ring are concentrically arranged, the rotation angle of the rotating block in the rotating slot is not greater than the rotation angle of a single ratchet tooth of the inner ratchet ring, and the ratchet tooth height of the outer ratchet ring is greater than the ratchet tooth height of the inner ratchet ring.

4. A torsion spring automatic injector according to claim 2 or 3, characterized in that: The injection component also includes a release spring, which is arranged in the knob. The two ends of the release spring respectively contact and connect the release button and the jumping tooth, so that the inner ratchet ring and the inner gear block remain engaged and the clutch cylinder is positioned at the first clutch cylinder axial position.

5. A torsion spring automatic injector according to claim 4, 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. Anti-drop buckles that cooperate with each other are provided between the guide rod and the clutch cylinder. When the clutch cylinder is positioned at the first clutch cylinder axial position, the anti-drop buckles between the guide rod and the clutch cylinder contact and cooperate with each other.

6. A torsion spring automatic injector according to claim 4, characterized in that: The dose setting component also includes a scale barrel, the inner wall of the scale barrel is slidably connected to the outer wall of the clutch barrel up and down, and the outer wall of the scale barrel is spirally slidably connected to the inner wall of the pen body; the inner wall of the scale barrel and the outer wall of the clutch barrel are provided with a plurality of guide rails and sliders that cooperate with each other, and the guide rails and sliders are evenly distributed on the inner wall of the scale barrel and the outer wall of the clutch barrel in a circumferential manner, and the clutch teeth and / or the pen body are provided with zero position limiting ribs and end limiting ribs that cooperate with the scale barrel.

7. A torsion spring automatic injector according to claim 1 or 2, characterized in that: The upper end of the clutch cylinder is connected to the jumping tooth by a ratchet or key connection, and the clutch cylinder and the jumping tooth can move axially up and down.

8. A torsion spring automatic injector according to claim 1 or 2, characterized in that: The injection component also includes a large push rod, the push rod driving member is installed in the pen body, the side wall of the push rod driving member is provided with a positioning block or a positioning groove to prevent the push rod driving member from rotating, the push rod driving member is provided with a first driving ratchet, the lower end of the large push rod is provided with a first driving ratchet connected and matched with the first driving ratchet, the push rod driving member is threadedly connected with the small push rod, 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 rib groove matching the small push rod, 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. When the dose is set, the clutch cylinder is positioned in the axial position of the first clutch cylinder, and the second driving ratchet and the second driving ratchet do not mesh with each other. When injecting, the clutch cylinder is positioned in the axial position of the second clutch cylinder, and the second driving ratchet and the second driving ratchet mesh with each other. The torsion spring drives the clutch cylinder and the large push rod to rotate, and the large push rod drives the small push rod to move spirally downward.

9. A torsion spring automatic injector according to claim 8, 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. When the first driving ratchet and the first driving ratchet are engaged and rotated, an injection reminder sound is emitted.

10. The torsion spring automatic injector according to claim 8, characterized in that: The injection component 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 undergo axial displacement 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.

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