Adjustable autoinjector
Patent Information
- Application Number
- PCT/CN2025/081485
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-02-18
- Filing Date
- 2025-03-10
- Publication Date
- 2026-08-27
Smart Images
Figure CN2025081485_27082026_PF_FP_ABST
Abstract
Description
An adjustable automatic injection device Technical Field
[0001] This invention relates to the field of medical device technology, and more specifically, to an adjustable automatic injection device. Background Technology
[0002] With the development of technology, injection devices have made great strides, evolving from the initial syringes to insulin pumps, and now to high-precision injection pens. The accuracy and convenience of injection devices have been greatly improved.
[0003] The market for injectable pen-related drugs has broad potential, with the diabetes and obesity sectors alone representing a market worth nearly $100 billion, and several new drugs are expected to be launched in quick succession.
[0004] Based on whether the medication can be replaced, injection pens can be divided into reusable injection pens and disposable injection pens. Reusable injection pens consist of the pen and a cartridge; the cartridge can be replaced after use, and the pen itself can be reused. Disposable injection pens are single-use injection devices assembled with the medication. The pen body and cartridge are integrated and cannot be disassembled; the cartridge does not need to be replaced during use and is discarded afterward.
[0005] Based on their operating principle, injection pens can be divided into mechanical injection pens and electronic smart injection pens. Mechanical injection pens are manually operated devices that require manual dosage adjustment. This technology has reached a relatively stable level and holds a dominant position in the market. Electronic smart injection pens are newer products that achieve the same functionality as mechanical injection pens using a motor-driven principle. They are typically equipped with an LCD screen and programmable functions, allowing for dosage setting and autonomous injection via a one-button operation, simplifying the injection process.
[0006] Patent document CN103249441B discloses an injection device comprising a housing for containing a syringe or cartridge for receiving a drug; a rotation drive shaft for rotating an adjustable predetermined amount to cause a corresponding amount of drug to be extruded from the syringe or cartridge; and a torsion drive spring fixed at one end region relative to the drive shaft and at the other end region to a connector adapted to non-rotatably engage a base on the housing.
[0007] Existing injection pens use torsion springs as energy storage devices. However, torsion springs have low energy storage density and cannot provide sufficient elasticity to meet the injection requirements of highly viscous drug solutions.
[0008] Therefore, it is necessary to propose an adjustable automatic injection device to solve the problems existing in the prior art. Summary of the Invention
[0009] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.
[0010] To address the above problems, the present invention provides an adjustable automatic injection device, comprising:
[0011] Pen body;
[0012] The main shaft is rotated within the pen body, and a push rod assembly is installed inside the main shaft.
[0013] The dosage knob is used for dosage setting and rewinding. When setting the dosage, it drives the spindle to rotate and stores energy in the energy storage component, which is mounted on the spindle.
[0014] The connecting component is located at the lower part of the spindle. It rotates with the spindle when the dose is set and restricts the spindle from reversing after setting. When the dose setting is excessive, the restriction on the spindle from reversing can be released. During injection, it is disconnected from the spindle.
[0015] A dosage limiting component is located inside the dosage knob to prevent the set total dosage from exceeding the total dosage of the drug solution;
[0016] The graduated cylinder is located outside the energy storage component inside the pen body. When the dosage is set, the graduated cylinder moves downward along the axis of the pen body. During injection, it moves in the opposite direction and returns to the initial position with a knocking sound when the injection is completed.
[0017] The energy storage component includes a spiral spring.
[0018] Preferably, the main shaft includes a shaft and a bushing, with a spline on the outer circumference of the shaft and a first keyway inside the dosage knob that engages with the spline.
[0019] Preferably, the connecting component includes a connector and an elastic element, and an annular tooth is provided on the lower end face of the connector, the annular tooth engaging with the annular tooth ring at the lower part of the inner wall of the pen body;
[0020] The connector is fitted onto the lower end of the bushing of the main shaft. Multiple first locking blocks are arranged in an array along the circumferential direction on the inner wall of the connector. Multiple second locking blocks corresponding to the first locking blocks are arranged in an array on the outer circumference of the lower end of the bushing. The first locking blocks and the second locking blocks are interlocked.
[0021] The elastic element is sleeved on the outside of the connector.
[0022] Preferably, the energy storage component also includes a sleeve, on the inner wall of which a second keyway is formed to engage with a spline, and a protrusion is provided on the outer circumference of the sleeve. One end of the spiral spring is engaged with the protrusion, and the other end of the spiral spring is connected to the pen body.
[0023] Preferably, the push rod assembly includes a push rod, a push handle, a push rod driver, and a nut. The nut is disposed inside the pen body, the push rod is threadedly connected to the nut, a cantilever is fixedly disposed at the lower end of the push rod driver, and ratchet teeth are disposed on the inner wall of the nut, with the cantilever engaged in the ratchet teeth.
[0024] Preferably, the push rod is disposed inside the push rod driver, a first contact surface is provided on the side of the push rod along the axis, and a second contact surface is provided on the inner wall of the push rod driver, the second contact surface being in contact with the first contact surface.
[0025] Preferably, multiple connector strips are arranged in an array along the circumferential direction on the upper part of the outer circumferential surface of the push rod driver, and slots are opened on the upper part of the inner wall of the bushing at positions corresponding to the connector strips, with the connector strips inserted into the slots.
[0026] Preferably, the outer circumference of the graduated cylinder is provided with graduations arranged along the axis, and a viewing window is opened on the pen body. When setting the dosage, the graduations on the graduated cylinder are displayed through the viewing window.
[0027] It also includes a medicine compartment, which is detachably connected to the pen body, and contains a cartridge bottle.
[0028] Preferably, it also includes a release assembly, which includes an injection button and a return spring. The injection button is movably disposed at the upper end of the dosage knob. When the injection button is pressed, it disengages the first locking block of the spindle from the second locking block of the connector. The return spring is disposed between the injection button and the dosage knob, and is used to drive the spindle back to its original position when the injection button is released.
[0029] Compared with the prior art, the present invention has at least the following beneficial effects:
[0030] The adjustable automatic injection device of the present invention has a main shaft rotating inside the pen body, and an energy storage component is provided on the main shaft. The dosage is set by the dosage button and the energy storage component stores energy. During injection, the spiral spring drives the main shaft to rotate and provides torque suitable for high viscosity liquids. If the dosage is adjusted too much, it can be corrected.
[0031] The adjustable automatic injection device of the present invention, other advantages, objectives and features of the present invention will be apparent in part from the following description, and in part will be understood by those skilled in the art through study and practice of the invention. Attached Figure Description
[0032] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:
[0033] Figure 1 is a schematic diagram of the disassembled structure of the adjustable automatic injection device disclosed in this invention.
[0034] Figure 2 is a cross-sectional structural schematic diagram of the adjustable automatic injection device disclosed in this invention;
[0035] Figure 3 is a schematic diagram of the main shaft disclosed in this invention;
[0036] Figure 4 is a schematic diagram of the dosage knob disclosed in this invention;
[0037] Figure 5 is a schematic diagram of the structure of the connector disclosed in this invention;
[0038] Figure 6 is a structural schematic diagram of the connector disclosed in this invention;
[0039] Figure 7 is a schematic diagram of the pen body structure disclosed in this invention;
[0040] Figure 8 is a schematic diagram of the structure of the elastic element disclosed in this invention;
[0041] Figure 9 is a schematic diagram of the structure of the sleeve disclosed in this invention;
[0042] Figure 10 is a schematic diagram of the push rod, push rod driver and nut disclosed in this invention;
[0043] Figure 11 is a schematic structural diagram of the main shaft section disclosed in this invention;
[0044] Figure 12 is a schematic diagram of the structure of the graduated cylinder disclosed in this invention;
[0045] Figure 13 is a schematic diagram of the front structure of the graduated cylinder disclosed in this invention;
[0046] Figure 14 is a schematic diagram of the connection between the graduated cylinder and the sleeve disclosed in this invention;
[0047] Figure 15 is a schematic diagram of the structure of the fixed gear and the limiting gear disclosed in this invention;
[0048] Figure 16 is a schematic diagram of the structure of the adjustment unit disclosed in the invention.
[0049] The components are as follows: 1. Main shaft, 1-1. Shaft, 1-2. Bushing, 1-3. Spline, 1-4. Second locking block, 1-5. Slot; 2. Spring base; 3. Fixing block; 4. Elastic element; 5. Connector, 5-1. Ring tooth, 5-2. First locking block; 6. Sleeve, 6-1. Second keyway, 6-2. Protrusion, 6-3. Threaded groove, 6-4. Wedge-shaped protrusion, 6-5. Cantilever groove, 6-6. Cantilever, 6-7. Protrusion, 6-8. Inclined surface; 8. Scale cylinder, 8-1. Rib, 8-2. Thread, 8-3. Locking groove, 8-4. Wedge-shaped groove, 8-5. Sound groove; 9. Push rod, 9-1. First contact surface, 9-2. Push rod thread; 10. Push 11. Handle; 12. Cartridge bottle; 13. Push rod actuator; 14. Cantilever; 15. Second contact surface; 16. Connecting strip; 17. Pen cap; 18. Nut; 19. Ratchet tooth; 20. Internal thread; 11. Medicine cartridge; 22. Spiral spring; 23. Pen body; 24. Ring toothed ring; 25. Guide groove; 26. Viewing window; 27. Dosage knob; 28. First keyway; 29. Return spring; 20. Injection button; 21. Needle tip; 22. Needle head; 23. Connecting block; 24. Adjusting cylinder; 25. Limiting cylinder; 26. Limiting ring; 27. Slide groove; 28. Slide plate; 29. Limiting gear; 30. Gear base. Detailed Implementation
[0050] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the description.
[0051] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.
[0052] As shown in Figures 1-15, the present invention provides an adjustable automatic injection device, comprising:
[0053] Pen body 17;
[0054] Main spindle 1, rotating within pen body 17, with push rod assembly installed within main spindle 1;
[0055] The dosage knob 18 is used for dosage setting and rewinding. When setting the dosage, it drives the spindle 1 to rotate and stores energy in the energy storage component, which is sleeved on the spindle 1.
[0056] The connecting component is located at the lower part of the main shaft 1. It rotates with the main shaft 1 when the dose is set, and restricts the main shaft 1 from reversing after setting. When the dose setting overdose knob 18 is reversed, the restriction on the reversal of the main shaft 1 can be released. During injection, it is disconnected from the main shaft 1.
[0057] A dosage limiting component is located within the dosage knob 18 to prevent the set total dosage from exceeding the total dosage of the liquid medicine.
[0058] The graduated cylinder 8 is located outside the energy storage component inside the pen body 17. When the dosage is set, the graduated cylinder 8 moves downward along the axis of the pen body 17, moves in the opposite direction during injection, and returns to the initial position with a knocking sound when the injection is completed.
[0059] The energy storage component includes a spiral spring 16.
[0060] Furthermore, the main shaft 1 includes a shaft 1-1 and a bushing 1-2. A spline 1-3 is provided on the outer circumference of the shaft 1-1, and a first keyway 18-1 is provided in the dosage knob 18 to cooperate with and connect with the spline 1-3.
[0061] Furthermore, the connecting assembly includes a connector 5 and an elastic element 4. A ring tooth 5-1 is provided on the lower end surface of the connector 5, and the ring tooth 5-1 is engaged with the ring tooth ring 17-1 at the lower part of the inner wall of the pen body 17.
[0062] The connector 5 is fitted onto the lower end of the bushing 1-2 of the main shaft 1. Multiple first locking blocks 5-2 are arranged in an array along the circumferential direction on the inner wall of the connector 5. Multiple second locking blocks 1-4 corresponding to the first locking blocks 5-2 are arranged in an array on the outer circumference of the lower end of the bushing 1-2. The first locking blocks 5-2 and the second locking blocks 1-4 are interlocked.
[0063] The elastic element 4 is sleeved on the outside of the connector 5.
[0064] Furthermore, the energy storage component also includes a sleeve 6. A second keyway 6-1 is formed on the inner wall of the sleeve 6 to connect with the spline 1-3. A protrusion 6-2 is provided on the outer circumference of the sleeve 6. One end of the spiral spring 16 is engaged with the protrusion 6-2, and the other end of the spiral spring 16 is connected to the pen body 17.
[0065] Furthermore, the push rod assembly includes a push rod 9, a push handle 10, a push rod driver 12, and a nut 14. The nut 14 is disposed inside the pen body 17. The push rod 9 is threadedly connected to the nut 14. A cantilever 12-1 is fixedly disposed at the lower end of the push rod driver 12. A ratchet tooth 14-1 is disposed on the inner wall of the nut 14. The cantilever 12-1 is engaged with the ratchet tooth 14-1.
[0066] Furthermore, the push rod 9 is disposed inside the push rod driver 12, and a first contact surface 9-1 is provided on the side of the push rod 9 along the axis, and a second contact surface 12-2 is provided on the inner wall of the push rod driver 12, and the second contact surface 12-2 contacts the first contact surface 9-1.
[0067] Furthermore, multiple connector strips 12-3 are arranged in an array along the circumferential direction on the upper part of the outer circumferential surface of the push rod driver 12. A slot 1-5 is opened on the upper part of the inner wall of the bushing 1-2 at a position corresponding to the connector strip 12-3, and the connector strip 12-3 is inserted into the slot 1-5.
[0068] Furthermore, the outer circumference of the graduated cylinder 8 is provided with graduations arranged along the axis, and a viewing window 17-4 is opened on the pen body 17. When setting the dosage, the graduations on the graduated cylinder 8 are displayed through the viewing window.
[0069] Furthermore, it also includes a medicine compartment 15, which is detachably connected to the pen body 17, and a cartridge bottle 11 is installed inside the medicine compartment 15.
[0070] Furthermore, it also includes a release assembly, which includes an injection button 20 and a return spring 19. The injection button 20 is movably disposed at the upper end of the dosage knob 18. When the injection button 20 is pressed, the first locking block 5-2 of the spindle 1 disengages from the second locking block 1-4 of the connector 5. The return spring 19 is disposed between the injection button 20 and the dosage knob 18, and is used to drive the spindle back to its original position when the injection button 20 is released.
[0071] The working principle of the above technical solution:
[0072] The syringe body 17 is a hollow cylindrical shape. A main shaft 1 is movably mounted inside the body 17. A sleeve 6 is fitted onto the outer circumference of the main shaft 1. The outer circumference of the sleeve 6 has protrusions 6-2 and threaded grooves 6-3 spaced apart. A second keyway 6-1, axially aligned with the inner wall of the sleeve 6, is formed. The second keyway 6-1 engages with a spline 1-3 on the outer circumference of the shaft 1-1. The main shaft 1 and the sleeve 6 can move axially. A dosage knob 18 is fitted onto the upper part of the sleeve 6 on the outer circumference of the main shaft 1. The dosage knob 18 contains... The first keyway 18-1 is connected to the spline 1-3. The dosage knob 18 is rotatably connected to the pen body 17. The main shaft 1 and the dosage knob 18 can move axially. A connector 5 is provided at the lower part of the inner sleeve 6 of the pen body 17. The connector 5 is sleeved on the lower end of the bushing 1-2 of the main shaft 1. Multiple first locking blocks 5-2 are arranged in an array along the circumferential direction on the inner wall of the connector 5. Multiple second locking blocks 1-4 corresponding to the first locking blocks 5-2 are arranged in an array on the outer circumference of the lower end of the bushing 1-2. The first locking blocks 5-2 and the second locking blocks 1-4 are interlocked. When setting the dosage, the first locking block 5-2 and the second locking block 1-4 are interlocked together. The connecting piece 5 rotates together with the main shaft 1. The annular tooth 5-1 at the lower end of the connecting piece 5 engages with the annular tooth ring 17-1 at the lower part of the inner wall of the pen body 17. A fixing block 3 is provided on the upper part of the connecting piece 5 inside the pen body 17. The fixing block 3 and the elastic element 4 are sleeved on the circumference of the connecting piece 5. One end of the elastic element 4 contacts the end face of the connecting piece 5, and the end face of the connecting piece 5 is opposite to the annular tooth 5-1. The other end of the elastic element 4... Contacting the lower end face of the fixing block 3, the connecting piece 5 is pressed by the elastic element 4, causing the annular gear ring 17-1 to lock the annular gear 5-1, preventing the main shaft 1 and the sleeve 6 from reversing, thus maintaining the elastic force of the spiral spring 16. One end of the spiral spring 16 is engaged with the protrusion 6-2, and the other end of the spiral spring can be fixedly connected to the pen body 17, or it can be connected to the pen body 17 through the spring base 2. When connected to the pen body through the spring base 2, the spiral spring is connected to the inner wall of the spring base 2, and the position between the spring base 2 and the pen body 17 is fixed.
[0073] The elastic element 4 can be a wave spring or a compression spring.
[0074] A push rod driver 12 is installed inside the shaft sleeve 1-2 of the main shaft 1. Multiple insert strips 12-3 are arranged in an array along the circumferential direction on the upper part of the outer circumferential surface of the push rod driver 12. Slots 1-5 are formed on the upper part of the inner wall of the bushing 1-2 at positions corresponding to the insert strips 12-3. During dosage setting, the insert strips 12-3 are disengaged from the slots 1-5. During injection, pressing the injection button 20 pushes the main shaft 1 downwards, causing the first locking block 5-2 to disengage from the second locking block 1-4. The connecting piece 5 no longer restricts the rotation of the main shaft 1. Simultaneously, the insert strips 12-3... 3. Inserted into slot 1-5, the main shaft begins to rotate under the action of the spiral spring 16. The main shaft 1 drives the push rod driver 12 to rotate. The push rod driver 12 drives the push rod 9 to rotate through the interaction between the second contact surface 12-2, which contacts the first contact surface 9-1 of the push rod 9. The outer circumference of the push rod 9 is provided with a thread 9-2, which cooperates with the internal thread 14-2 of the nut 14. During the rotation of the push rod 9, it is acted upon by the nut 14 and moves towards the lower end of the injection pen. Through the push handle 10 connected to the lower end of the push rod 9, it pushes the piston in the cartridge 11 to move, thus completing the injection.
[0075] The cartridge bottle 11 is placed inside the medicine compartment 15, and the medicine compartment 15 is detachably connected to the pen body 17.
[0076] A thread 8-2 is fixedly provided on the inner wall of the graduated cylinder 8, and a threaded groove 6-3 is opened on the outer circumference of the sleeve 6. The thread 8-2 is connected to the threaded groove 6-3 of the sleeve 6.
[0077] The outer circumference of the graduated cylinder 8 is provided with graduations arranged along the axial direction, and a viewing window 17-4 is opened on the pen body 17. When setting the dosage, the graduations on the graduated cylinder 8 are displayed through the viewing window.
[0078] When the upper end of the thread 8-2 contacts the upper end of the thread groove, the scale displayed in the viewing window of the scale cylinder 8 is zero. The lower end of the scale cylinder 8 has a slot 8-3, and the lower end of the sleeve 6 is provided with a wedge-shaped protrusion 6-4. When the dosage knob is set to the maximum dosage, the wedge-shaped protrusion 6-4 is engaged in the slot 8-3, and the slot 8-3 is wedge-shaped.
[0079] A wedge-shaped groove 8-4 is provided on the upper end face of the graduated cylinder 8, and a sound groove 8-5 is provided at the bottom of the wedge-shaped groove 8-4;
[0080] A cantilever groove 6-5 is formed on the outer circumference of the sleeve 6. A cantilever 6-6 is fixedly installed on one side wall of the cantilever groove 6-5. The shape of the cantilever 6-6 is adapted to the shape of the outer wall of the sleeve 6. A protrusion 6-7 is fixedly installed on the outer side of the cantilever end of the cantilever 6-6. When the sleeve 6 is injected, it reverses and the protrusion 6-7 slides into the sound groove 8-5 along the bottom surface of the wedge groove 8-4 and hits the bottom of the sound groove 8-5 to make a sound.
[0081] The surface of the protrusion 6-7 facing the root of the cantilever 6-6 is a slope 6-8.
[0082] At the "0" mark, the protrusion 6-7 of the cantilever 6-6 of the sleeve 6 is just embedded in the sound groove 8-5 of the scale cylinder 8 and contacts the left side wall of the sound groove 8-5. The stop block 28 contacts the right side wall of the sound groove 8-5 of the scale cylinder 8, and the scale of the scale cylinder 8 is displayed as "0".
[0083] During dosage adjustment, when the inclined surface 6-8 of the protrusion 6-7 of the cantilever 6-6 contacts the left side wall of the sound groove 8-5, the cantilever 6-6 is lifted upward by the wedge groove 8-4 under the action of the inclined surface 6-8 and slides along the bottom of the wedge groove. As the scale cylinder 8 continues to move downward, the cantilever 6-6 returns to its free state. The inclined surface 6-8 tilts from top to bottom towards the suspended end of the cantilever 6-6.
[0084] During injection, the sleeve 6 is reversed, and the graduated cylinder 8 moves upward. The upper end of the graduated cylinder 8 approaches the cantilever 6-6. When the bottom surface of the wedge groove 8-4 contacts the lower surface of the protrusion 6-7, the cantilever 6-6 is gradually lifted. The protrusion 6-7 slides along the bottom surface of the wedge groove onto the sound groove 8-5. At the moment when the protrusion 6-7 slides out of the wedge groove 8-4 and into the sound groove 8-5, under the elastic action of the cantilever, the lower surface of the protrusion 6-7 strikes the bottom surface of the sound groove 8-5, producing a striking sound to remind the patient that the injection is complete.
[0085] First, remove the pen cap 13 and screw on the needle.
[0086] Adjusting the dosage: Hold the pen body 17 with one hand and rotate the dosage knob 18 with the other hand. At this time, the main shaft 1 starts to rotate because the first keyway 18-1 inside the dosage knob 18 and the spline 1-3 of the main shaft 1 cooperate with each other. The outer wall of the dosage knob 18 has an anti-slip groove 18-2 set along the axial direction. According to the ergonomic design, it increases the feel and makes it easier to grip the knob and apply force, so as not to slip or other phenomena.
[0087] Since the spline 1-3 of the spindle 1 and the second keyway 6-1 of the sleeve 6 are connected, when the sleeve 6 starts to rotate, the scroll spring 16 starts to rotate and store force. The protrusion 6-2 of the sleeve 6 is stuck at one end of the scroll spring 16, that is, the inner end is fixed to the sleeve 9; the other end is formed by spot welding or folding to make an outward-folding shape, which is stuck in the base 2.
[0088] Because the external thread 6-3 of the sleeve 6 and the internal thread 8-2 of the scale cylinder 8 are connected, and the vertically arranged rib 8-1 of the scale cylinder 8 is engaged in the guide groove 17-2 of the pen body 17, when the sleeve 6 rotates, the external thread 6-3 of the sleeve 6 and the pen body 17 acting on the rib 8-1 together cause the scale cylinder 8 to move vertically downwards. The dosage number of the scale cylinder 8 is displayed through the viewing window 17-4 of the pen body 17, thus completing the dosage adjustment. During dosage adjustment, the cantilever 6-6 is lifted upwards by the wedge groove 8-4 under the action of the inclined plane 6-8 and slides along the bottom of the wedge groove. As the scale cylinder 8 continues to move downwards, the cantilever 6-6 returns to its free state. The inclined plane 6-8 tilts from top to bottom towards the suspended end of the cantilever 6-6.
[0089] The main shaft 1 rotates, and the second locking block 1-4 and the first locking block 5-2 of the connector 5 interlock, driving the connector 5 to rotate. The teeth of the annular gear 5-1 pass over the teeth of the annular gear ring 17-1 of the pen body 17, and under the pressure of the elastic element 4, it makes a "clicking" sound when rotating. Since the reverse angle of the teeth of the annular gear ring 17-1 of the pen body 17 is small, it plays a role in locking the connector 5, thereby locking the entire transmission structure. When the adjusted dosage is greater than the expected injection dosage, Rotate the dosage knob 18 in the reverse direction. The dosage knob 18 drives the connecting piece 5 to rotate in the reverse direction through the main shaft 1. At this time, a larger force is used to rotate the dosage knob 18 in the reverse direction. When the force of the reverse rotation is large, the upward force generated by the ring gear 17-1 exceeds the downward pressure of the elastic element 4. Then the teeth of the ring gear 5-1 will forcibly pass over the teeth of the ring gear 17-1, and a "clicking" sound will be made. The reverse rotation of the main shaft 1 will also drive the sleeve 6 to rotate in the reverse direction, and the scale cylinder 8 will also move in the reverse direction, thereby completing the rotation of the main shaft 1 and the scale adjustment.
[0090] After the dosage adjustment is completed, press the injection button 20. As the spindle 1 moves downward, the upper end of the spline 1-3 of the spindle 1 slowly disengages from the first keyway 18-1 of the dosage knob 18; the second locking block 1-4 of the spindle 1 and the first locking block 5-2 of the connector 5 slowly disengage; simultaneously, the slot 1-5 of the spindle 1 and the connector strip 12-3 of the driver 12 engage; when the second locking block 1-4 of the spindle 1 and the first locking block 5-2 of the connector 5 are completely disengaged, the spline 1-3 of the spindle 1 has already disengaged from the first keyway 18-1 of the dosage knob 18; at the same time, the slot 1-5 of the spindle 1 and the connector strip 12-3 of the push rod driver 12 have also completed engagement; at this point, the spiral spring 16 begins to release, driving the sleeve 6, and then the scale cylinder 8 rotates back. At zero, the spindle 1 drives the push rod driver 12. Since the second contact surface 12-2 of the push rod driver 12 and the first contact surface 9-1 of the push rod 9 are in contact, the push rod 9 rotates under the action of the push rod driver 12. The external thread 9-2 of the push rod 9 begins to move downward under the action of the internal thread 14-2 of the nut 14, that is, the injection of medicine begins. As the cantilever 12-1 of the push rod driver 12 passes over the ratchet tooth 14-1 of the nut 14, a "clicking" sound is emitted to remind the patient that the injection is in progress. At the moment when the dial is zeroed after the injection is completed, the protrusion 6-7 slides out of the wedge groove 8-4 and enters the sound groove 8-5. Under the elastic action of the cantilever, the lower surface of the protrusion 6-7 hits the bottom surface of the sound groove 8-5, producing an impact sound to remind the patient that the injection is over.
[0091] When the external force is removed, the main spindle 1 is driven to return to its original position by the return spring 19. During the return, the spline 1-3 of the main spindle 1 and the first keyway 18-1 of the dosage knob 18 slowly engage; the second locking block 1-4 of the main spindle 1 and the first locking block 5-2 of the connector 5 also begin to engage; at the same time, the slot 1-5 of the main spindle 1 and the plug bar 12-3 of the push rod driver 12 slowly disengage.
[0092] Due to the interaction between the cantilever 12-1 of the push rod driver 12 and the ratchet teeth 14-1 of the nut 14, after the slot 1-5 and the connector strip 12-3 of the push rod driver 12 are disengaged, the push rod 9 will not rotate in the opposite direction under the action of the rubber plug, but will stay in the original position.
[0093] As shown in Figure 15, to prevent the cumulative dose set during dosage setting from exceeding the total medication volume in the cartridge 11 of the injection pen, a dosage limiting component is provided inside the dosage knob 18. This component includes a fixed gear 2-1 mounted on the spring base 2. The dosage knob 18 is sleeved on the upper part of the spring base 2 and rotatably connected to it. A limiting gear 29 is rotatably mounted inside the dosage knob 18, meshing with the fixed gear 2-1. The limiting gear 29 rotates on its own axis while simultaneously revolving around the axis of the pen body 17. The number of teeth on the limiting gear 29 is less than the number of teeth on the fixed gear 2-1. The fixed gear 2-1 is mounted on the outer wall of the spring base 2. A baffle 2-2 is fixedly installed at the lower part of the 1, and a stop block 29-1 is fixedly installed at the lower part of the limiting gear 29. In the initial position, the stop block 29-1 is in contact with one side of the baffle 2-2. Since the number of teeth of the limiting gear 29 is less than the number of teeth of the fixed gear 2-1, when the dose knob 18 drives the limiting gear 29 to revolve, the dose knob 18 rotates one revolution, and the limiting gear 29 rotates the corresponding number of teeth more. When the dose set by the dose knob 18 goes from zero to the maximum dose, the stop block 29-1 just rotates from one side of the baffle 2-2 to the other side and is blocked by the baffle 2-2. At the same time, under the combined action of gear meshing, the dose knob can no longer rotate. At this time, the entire dose setting of the pen is completed.
[0094] A connecting plate is fixedly installed inside the dosage knob 18, which can rotate the limiting gear 29 onto the gear shaft on the lower end face of the connecting plate. Alternatively, a gear base 30 can be installed inside the dosage knob 18, and the limiting gear 29 can rotate onto the gear base 30.
[0095] The beneficial effects of the above technical solution are as follows:
[0096] The adjustable automatic injection device of the present invention has a main shaft rotating inside the pen body, and an energy storage component is provided on the main shaft. The dosage is set by the dosage button and the energy storage component stores energy. During injection, the spiral spring drives the main shaft to rotate and provides torque suitable for high viscosity liquids. If the dosage is adjusted too much, it can be corrected.
[0097] In one embodiment, a subcutaneous fat thickness detection module is provided at the bottom inside the pen cap 13. The subcutaneous fat thickness detection unit includes a controller, an ultrasonic pulse emitting module, and an ultrasonic receiving module. The ultrasonic pulse emitting module and the ultrasonic receiving module are electrically connected to the controller. The controller calculates the thickness of the subcutaneous fat based on the time it takes for the ultrasonic waves emitted by the ultrasonic pulse emitting module to reach the interface between the subcutaneous fat and muscle and return to the ultrasonic receiving module.
[0098] The controller uses the following formula to calculate the thickness of subcutaneous fat:
[0099] Where: δ is the subcutaneous fat thickness, n is the number of emitted pulse ultrasound waves, t is the time it takes for the ultrasound wave to return after reaching the interface between subcutaneous fat and muscle, i is the range of the number of pulse ultrasound waves emitted, and v is the propagation speed of ultrasound waves in subcutaneous fat, selected as 975~1225 m / s.
[0100] The controller is electrically connected to the display unit, which can be a sound-generating device or an image display device, and the display unit is located on the outer circumference of the pen cap.
[0101] The patient sets the injection depth of the needle tip 21 based on the subcutaneous fat thickness measured by the subcutaneous fat thickness detection module. The needle tip 21 is fixedly mounted on the connecting block 23 of the needle head 22. An adjustment unit is provided on the needle head 22 to adjust the injection depth of the needle tip 21. The adjustment unit includes an adjustment cylinder 24 rotatably mounted on the outer circumference of the needle head 22. The adjustment cylinder 24 is cylindrical. A limiting cylinder 25 is threadedly connected to the inner wall of the adjustment cylinder 24. A limiting ring 26 is fixedly mounted on the lower end face of the limiting cylinder 25. Two sliding grooves 27 are symmetrically opened along the axial direction on the outer wall of the connecting block 23 of the needle head 22. A sliding plate 28 is fixedly mounted on the upper end face of the limiting ring 26 at a position corresponding to the sliding groove 27. The sliding plate 28 is slidably mounted in the sliding groove 27.
[0102] The working principle and beneficial effects of the above technical solution:
[0103] When using an injection pen, subcutaneous injection is often used. However, due to differences in individual physique and body size, the thickness of subcutaneous fat varies, making it difficult for patients to determine the depth of needle insertion during the use of the injection pen.
[0104] A subcutaneous fat thickness detection module is installed at the bottom inside the pen cap 13. The subcutaneous fat thickness detection unit includes a controller, an ultrasonic pulse emitting module, and an ultrasonic receiving module. The ultrasonic pulse emitting module and the ultrasonic receiving module extend through the bottom surface of the pen cap 13 to the outside of the bottom surface of the pen cap 13. Before injection, the injection site is selected, a small amount of coupling agent is applied to the injection site, and then the probe is placed on the injection site to contact the skin. The probe emits pulsed ultrasonic waves according to the control of the controller. The controller calculates the patient's subcutaneous fat thickness based on the return time of multiple pulsed ultrasonic waves.
[0105] As shown in Figure 16, the needle 22 is connected to the drug cartridge 15 via an internal thread, and the needle tip 21 is fixed by a connecting block 23. The length of the needle tip 21 protruding from the connecting block 23 is the maximum injection depth, which can be set as needed. An axially oriented graduated groove is formed on the outer circumference of the limiting cylinder 25, marking the injection depth. The lowest edge of the limiting cylinder 25 represents the maximum injection depth of the needle tip, gradually decreasing upwards to zero. After measuring the thickness of the subcutaneous fat, the adjusting cylinder 24 is rotated. Therefore, the limiting cylinder 25 and the adjusting cylinder 24 are threadedly connected, and the sliding groove 27 limits... The sliding plate 28 can only move along the axis of the needle tip 21. When the adjusting cylinder is rotated, the limiting cylinder 25 drives the limiting ring 26 to move downward, so that the value of half the subcutaneous fat thickness is aligned with the scale in the groove on the limiting cylinder 25 and the lower end face of the adjusting cylinder 24. The exposed length of the needle tip 21 is the same as half the subcutaneous fat thickness. Then, the injection site is disinfected, the injection pen is vertically aligned with the injection site, and the needle tip 21 is inserted into the skin so that the limiting ring 26 contacts the skin. The injection depth is half the thickness of the subcutaneous fat, so that all the medicine can be injected into the subcutaneous fat.
[0106] Intramuscular injections are performed using the same principle, with the needle tip's exposed length set to allow it to penetrate the muscle layer; this will not be elaborated upon further here.
[0107] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0108] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0109] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.
Claims
1. An adjustable automatic injection device, characterized in that, include: Pen body (17); The main shaft (1) is rotatably set inside the pen body (17), and a push rod assembly is set inside the main shaft (1); The dose knob (18) is used for dose setting and rewinding. When the dose is set, it drives the spindle (1) to rotate and stores energy in the energy storage component, which is mounted on the spindle (1). The connecting component is located at the lower part of the main shaft (1). When the dose is set, it rotates with the main shaft (1) and restricts the main shaft (1) from reversing after setting. When the dose setting overdose knob (18) is reversed, the restriction on the reversal of the main shaft (1) can be released. When injecting, it is disconnected from the main shaft (1). A dose limiting component is located inside the dose knob (18) to prevent the set total dose from exceeding the total dose of the liquid medicine; The graduated cylinder (8) is located outside the energy storage component inside the pen body (17). When the dose is set, the graduated cylinder (8) moves downward along the axis of the pen body (17), moves in the opposite direction during injection, and returns to the initial position and makes a knocking sound when the injection is completed. The energy storage component includes a spiral spring (16).
2. The adjustable automatic injection device according to claim 1, characterized in that, The main shaft (1) includes a shaft (1-1) and a bushing (1-2). A spline (1-3) is provided on the outer circumference of the shaft (1-1), and a first keyway (18-1) is provided in the dose knob (18) to cooperate with the spline (1-3).
3. The adjustable automatic injection device according to claim 2, characterized in that, The connecting component includes a connector (5) and an elastic element (4). A ring tooth (5-1) is provided on the lower end surface of the connector (5). The ring tooth (5-1) is connected to the ring tooth ring (17-1) at the lower part of the inner wall of the pen body (17). The connector (5) is sleeved on the lower end of the bushing (1-2) of the main shaft (1). Multiple first locking blocks (5-2) are arranged in an array along the circumferential direction on the inner wall of the connector (5). Multiple second locking blocks (1-4) corresponding to the first locking blocks (5-2) are arranged in an array on the outer circumference of the lower end of the bushing (1-2). The first locking blocks (5-2) and the second locking blocks (1-4) are inserted into each other. The elastic element (4) is sleeved on the outside of the connector (5).
4. The adjustable automatic injection device according to claim 3, characterized in that, The energy storage component also includes a sleeve (6), on the inner wall of the sleeve (6) a second keyway (6-1) is provided to connect with the spline (1-3), a protrusion (6-2) is provided on the outer circumference of the sleeve (6), one end of the spiral spring (16) is engaged with the protrusion (6-2), and the other end of the spiral spring (16) is connected to the pen body (17).
5. The adjustable automatic injection device according to claim 4, characterized in that, The push rod assembly includes a push rod (9), a push handle (10), a push rod driver (12), and a nut (14). The nut (14) is located inside the pen body (17). The push rod (9) is threadedly connected to the nut (14). A cantilever (12-1) is fixedly installed at the lower end of the push rod driver (12). A ratchet tooth (14-1) is provided on the inner wall of the nut (14). The cantilever (12-1) is engaged with the ratchet tooth (14-1).
6. The adjustable automatic injection device according to claim 5, characterized in that, The push rod (9) is located inside the push rod driver (12). A first contact surface (9-1) is provided on the side of the push rod (9) along the axis, and a second contact surface (12-2) is provided on the inner wall of the push rod driver (12). The second contact surface (12-2) contacts the first contact surface (9-1).
7. The adjustable automatic injection device according to claim 6, characterized in that, Multiple connector strips (12-3) are arranged in an array along the circumferential direction on the upper part of the outer circumferential surface of the push rod driver (12). A slot (1-5) is opened on the upper part of the inner wall of the bushing (1-2) at the position corresponding to the connector strip (12-3), and the connector strip (12-3) is inserted into the slot (1-5).
8. The adjustable automatic injection device according to claim 7, characterized in that, The outer circumference of the graduated cylinder (8) is provided with graduations arranged along the axis, and a viewing window (17-4) is opened on the pen body (17). When setting the dosage, the graduations on the graduated cylinder (8) are displayed through the viewing window.
9. The adjustable automatic injection device according to claim 8, characterized in that, It also includes a medicine compartment (15), which is detachably connected to the pen body (17), and a cartridge bottle (11) is installed inside the medicine compartment (15).
10. The adjustable automatic injection device according to claim 8, characterized in that, It also includes a release assembly, which includes an injection button (20) and a return spring (19). The injection button (20) is movably disposed at the upper end of the dosage knob (18). When the injection button (20) is pressed, the first locking block (5-2) of the spindle (1) disengages from the second locking block (1-4) of the connector (5). The return spring (19) is disposed between the injection button (20) and the dosage knob (18) and is used to drive the spindle back to its original position when the injection button (20) is released.