A precision syringe pump and method of controlling the same

Abstract

The application discloses a precision injection pump and a control method thereof. The precision injection pump comprises a base, a liquid storage system fixed on the base, a control system and a needle feeding system, and a circuit system; the liquid storage system comprises a liquid storage device fixed on the base, and a liquid inlet and outlet control assembly arranged in the liquid storage device; the control system comprises a gear and a transmission assembly fixed on the base, and a sliding assembly in contact with the gear; the gear is connected with the liquid inlet and outlet control assembly and the needle feeding system respectively, and the transmission assembly is connected with the sliding assembly; the control system drives the liquid inlet and outlet control assembly to move through rotation of the gear, so as to control the delivery of liquid in the liquid storage system and the movement of the needle feeding system to realize needle feeding and needle discharging; the circuit system is connected with the transmission assembly and is used for energizing or de-energizing the transmission assembly, so as to drive the gear to rotate through the sliding assembly. The precision injection pump is simple in design, small in size, light in weight and low in cost, and is convenient to carry.

Description

Technical Field

[0001] This invention relates to the field of syringe pump technology, and in particular to a precision syringe pump and its control method. Background Technology

[0002] Precision syringe pumps are high-precision instruments for injecting liquid media, suitable for applications requiring high injection volume accuracy. Due to their low injection error, existing precision syringe pumps are widely used in the medical, precision chemical, and metrology industries.

[0003] Currently, precision syringe pumps on the market use high-precision motors and matching balancing devices, which suffer from drawbacks such as complex manufacturing, high process requirements, high cost, and high mechanical failure rate after long-term use. To address these shortcomings, some patents propose developing precision syringe pumps using materials such as electro-thin films, electrets, and magnets as drive devices. These pumps require four essential systems: a liquid storage system, a control system, a needle insertion system, and a circuit system. Their main difference lies in the control system. Developing precision syringe pumps using electro-thin films, electrets, and magnets as drive devices primarily involves improving the pump by modifying the control system. However, electro-thin films, electrets, and magnets have drawbacks such as high voltage requirements, large size, and heavy weight. In commercially available precision syringe pumps, the liquid in the liquid reservoir is usually filled during assembly. However, if the active ingredient in the liquid is unstable, failures may occur during assembly and transportation. If the recipient of a high-precision syringe pump is a human or animal body, a needle insertion system is required. Currently, most needle insertion systems on the market are individually controlled or separate systems, with complex designs. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems of large volume and heavy weight of existing precision injection pumps, and to provide a precision injection pump and its control method.

[0005] The technical problem of this invention is solved by the following technical solution:

[0006] A precision injection pump includes: a base, a liquid storage system, a control system, and a needle insertion system fixed to and connected to the base, and a circuit system; the liquid storage system includes a liquid reservoir fixed to the base, and a liquid inlet / outlet control component is disposed inside the liquid reservoir; the control system includes a gear and a transmission component fixed to the base, and a sliding component in contact with the gear, the gear being connected to the liquid inlet / outlet control component and the needle insertion system respectively, and the transmission component being connected to the sliding component; the control system drives the liquid inlet / outlet control component to move through the rotation of the gear, thereby controlling the delivery of liquid in the liquid storage system and controlling the movement of the needle insertion system to achieve needle insertion and withdrawal; the circuit system is connected to the transmission component and is used to energize or de-energize it, thereby driving the gear to rotate through the sliding component.

[0007] In some embodiments, the needle insertion system includes a locking structure, a helical torsion spring fixed on a base, a connecting locking structure, a connecting structure, a third slider, a fourth slider, a steel needle, and a guide tube. The locking structure is connected to the gear and the connecting locking structure, respectively. The connecting locking structure is connected to the helical torsion spring and the connecting structure, respectively. The third slider and the fourth slider are on the same track. The third slider is connected to the connecting structure and the steel needle, respectively. The fourth slider is connected to the guide tube. The rotation of the gear causes the helical torsion spring to drive the connecting locking structure to rotate, thereby pushing the third slider and the fourth slider to move along the same track.

[0008] In some embodiments, the transmission assembly includes a first spring, a second spring, a first electrochromic alloy wire, and a second electrochromic alloy wire, with one end of each of the first spring, the second spring, the first electrochromic alloy wire, and the second electrochromic alloy wire respectively fixed to the base; the sliding assembly includes a first slider and a second slider, with one end of the first slider and the second slider respectively contacting the gear; the first spring is sleeved on the first electrochromic alloy wire, with the other end of the first spring and the first electrochromic alloy wire respectively connected to the other end of the first slider; the second spring is sleeved on the second electrochromic alloy wire, with the other end of the second spring and the second electrochromic alloy wire respectively connected to the other end of the second slider; both ends of the first electrochromic alloy wire and the second electrochromic alloy wire are connected to the circuit system.

[0009] In some embodiments, the first slider is connected to the root of the gear teeth, and the second slider is connected to the gear teeth at halfway point. When the circuit system energizes the first electrochromic alloy wire, the first electrochromic alloy wire contracts, causing the first slider to slide in the direction of disengagement from the gear. The second spring returns from a mid-range compression state to its longest compression state, pushing the second slider to rotate the gear until the second slider contacts the root of the gear teeth, at which point the first spring is in its shortest compression state. When the circuit system de-energizes the first electrochromic alloy wire, the first spring returns to its mid-range compression state, causing the gear to rotate. The first slider reaches halfway down the tooth surface of the gear; the gear completes a 0.5-tooth rotation; when the circuit system energizes the second electrochromic alloy wire, the second electrochromic alloy wire contracts, causing the second slider to slide towards disengagement from the gear; when the first slider contacts the gear, it pushes the gear to rotate, and the second spring is in its shortest compression state; when the circuit system de-energizes the second electrochromic alloy wire, the second spring returns from its shortest compression state to its mid-range compression state, causing the second slider to slide towards the gear until it contacts the gear; the gear completes another 0.5-tooth rotation.

[0010] In some embodiments, the contact point between the first slider, the second slider, and the gear is at halfway point of the gear tooth surface. When the circuit system energizes the first electrochromic alloy wire, the first electrochromic alloy wire drives the first slider to slide in the direction of disengagement from the gear, and the first spring begins to compress. When the first slider disengages from the gear, the energy stored in the second spring begins to be released, pushing the gear to rotate 0.5 teeth. When the circuit system de-energizes the first electrochromic alloy wire, the first spring recovers from its shortest compression state to its medium compression state, pushing the first slider to slide along the track towards the gear until it contacts the gear. The second slider contacts the gear, the gear is in a cut-off state, the first slider stops moving, and the remaining energy stored in the first spring will be used to energize the second electrochromic alloy wire. When the circuit system energizes the second electrochromic alloy wire, the second electrochromic alloy wire drives the second slider to slide along the track towards the gear, and the second spring begins to compress; when the second slider and the gear disengage, the energy stored in the first spring begins to be released, pushing the gear to rotate another 0.5 teeth; when the circuit system de-energizes the second electrochromic alloy wire, the second spring recovers from the shortest compression state to the middle compression state, pushing the second slider to slide along the track towards the gear until it contacts the gear; when the first slider and the gear are in contact, the gear is in the off state, the second slider stops moving, and the remaining energy stored in the second spring will be released when the first electrochromic alloy wire is energized and the first slider disengages from the gear.

[0011] In some embodiments, the liquid inlet / outlet control assembly includes a piston, a screw, and a hexagonal stud. The piston is located inside the reservoir, and the screw is fixedly connected to the surface of the piston. A hexagonal stud is connected to the end of the screw away from the piston, and the hexagonal stud is connected to the gear.

[0012] In some embodiments, the screw pitch is 0.1mm-5mm, and the volume of liquid transported by the screw in one rotation is 0ml-5ml; the top of the hexagonal stud is provided with a snap-fit ​​structure, which can deform under force, so that the hexagonal stud and the gear remain relatively stationary; there is a gap of 0mm-0.5mm between the hexagonal stud and the inner wall of the gear.

[0013] In some embodiments, the bottom of the liquid reservoir is provided with an inlet and an outlet, both of which are sealed with rubber stoppers; the cross-sectional shape of the liquid reservoir is non-circular; one end of the liquid reservoir is provided with an opening, and the piston is equipped with a rubber ring to seal the opening; the piston can move radially as liquid is injected or discharged; the liquid reservoir system also includes a positioning rod, which is fixedly connected to the piston surface.

[0014] In some embodiments, the phase difference between the first slider and the second slider is 120°-240°.

[0015] This invention also proposes a precision injection pump control method. Based on the aforementioned precision injection pump, the method includes the following steps: S1, storing the liquid: after the precision injection pump is assembled, the liquid to be injected is injected into the reservoir; S2, introducing the needle insertion system: connecting the needle insertion system and the control system, and controlling the needle insertion system to insert the needle through the control system; S3, receiving the injection command: after the needle insertion system inserts the needle, when liquid injection is required, the circuit system receives the injection command emitted from the outside; S4, issuing a drive command: the circuit system issues a drive command, converting the volume of liquid to be injected into the number of times the transmission component in the control system is energized; S5, executing the drive command: the circuit system controls the energization and de-energization of the transmission component to precisely deliver the liquid.

[0016] The beneficial effects of this invention compared to the prior art include:

[0017] The precision infusion pump and its control method provided by this invention use a circuit system to energize or de-energize the transmission component, causing the sliding component to move, which in turn drives the gear to rotate. The control system, through the rotation of the gear, drives the liquid inlet / outlet control component to move, thereby controlling the delivery of liquid in the reservoir system and controlling the movement of the needle insertion system to achieve needle insertion and withdrawal, thus completing the liquid injection. Both the reservoir system and the needle insertion system of this invention are controlled by the gears of the control system, eliminating the need for a separate needle insertion system or needle insertion control system. Therefore, the precision infusion pump of this invention is simple in design, small in size, lightweight, and low in cost, making it easy to carry and use as a patch-type precision drug injection system, especially with broad application prospects in diabetes management.

[0018] In some embodiments, the needle insertion system is connected to the gear and the connecting locking structure through the locking structure. The connecting locking structure is connected to the helical torsion spring and the connecting structure. The rotation of the gear causes the helical torsion spring to drive the connecting locking structure to rotate, pushing the third slider and the fourth slider to move along the same track, thereby driving the steel needle and the catheter to move, thus realizing needle insertion and needle withdrawal, further reducing the size and weight of the precision injection pump.

[0019] In some embodiments, the control system causes the first and second sliders to slide by switching the first and second electrochromic alloy wires on and off, while simultaneously causing the first and second springs to contract and stretch, thereby driving the gear to rotate. This control system has a simple structure, further reducing the size and weight of the precision injection pump.

[0020] In some embodiments, one end of the reservoir is provided with an opening. After the precision injection pump is assembled, the liquid to be injected can be injected into the reservoir through the opening. Then, the opening is sealed by a piston with a rubber ring to store the liquid, thereby maximizing the stability of the liquid during transportation.

[0021] Other beneficial effects of the embodiments of the present invention will be further described below. Attached Figure Description

[0022] Figure 1 This is a flowchart of the precision injection pump control method in an embodiment of the present invention.

[0023] Figure 2 This is a perspective view of the precision injection pump in an embodiment of the present invention.

[0024] Figure 3 This is a schematic diagram of the liquid storage system in an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the control system in an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the needle insertion system in an embodiment of the present invention.

[0027] Figure 6 This is a schematic diagram of the base in an embodiment of the present invention.

[0028] Figure 7a This is a schematic diagram of the liquid storage system in an embodiment of the present invention when no liquid is injected.

[0029] Figure 7b This is a schematic diagram of the liquid storage system injecting liquid in an embodiment of the present invention.

[0030] Figure 7cThis is a schematic diagram of the stud snap structure of the liquid storage system abutting against the first limiting surface in an embodiment of the present invention.

[0031] Figure 7d yes Figure 7c Enlarged view of point A in the middle.

[0032] Figure 7e This is a schematic diagram of the liquid storage system completing liquid injection in an embodiment of the present invention.

[0033] Figure 7f yes Figure 7e Enlarged view of point A in the middle.

[0034] Figure 8 This is a schematic diagram of the liquid reservoir in an embodiment of the present invention.

[0035] Figure 9a This is a schematic diagram of the initial state of the control system in an embodiment of the present invention.

[0036] Figure 9b This is a schematic diagram of the control system when the first energized variable alloy wire is energized in an embodiment of the present invention.

[0037] Figure 9c This is a schematic diagram of the control system when the first energized variable alloy wire is de-energized in an embodiment of the present invention.

[0038] Figure 9d This is a schematic diagram of the control system when the second energized variable alloy wire is energized in an embodiment of the present invention.

[0039] Figure 10a This is a schematic diagram of the initial state of the needle insertion system in an embodiment of the present invention.

[0040] Figure 10b yes Figure 10a Enlarged view of point B.

[0041] Figure 10c This is a schematic diagram of the first working state of the needle insertion system in an embodiment of the present invention.

[0042] Figure 10d This is a schematic diagram of the second working state of the needle insertion system in an embodiment of the present invention.

[0043] Figure 11 This is a graph showing the relationship between the total number of energizations of the first and second electrochromic alloy wires and the balance reading in an embodiment of the present invention.

[0044] Figure 12 This is a schematic diagram of the standard curve of ultraviolet absorption of insulin solution in an embodiment of the present invention.

[0045] Figure 13This is a schematic diagram illustrating the total number of energizations and the amount of insulin delivered by the first and second electrochromic alloy wires in an embodiment of the present invention.

[0046] Figure 14 This is a schematic diagram of the bottom of the reservoir in an embodiment of the present invention.

[0047] Figure 15 This is a three-dimensional structural diagram of the snap-fit ​​structure at the top of the hexagonal stud in an embodiment of the present invention.

[0048] Figure 16 This is a three-dimensional cross-sectional schematic diagram of the first and second limiting surfaces of the gear in an embodiment of the present invention.

[0049] Figure 17a This is a schematic diagram of the state of the spiral torsion spring release advance needle system in an embodiment of the present invention.

[0050] Figure 17b This is an embodiment of the present invention. Figure 17a Enlarged view of point C.

[0051] Figure 18a This is a schematic diagram of the needle insertion system after the release of the helical torsion spring in an embodiment of the present invention.

[0052] Figure 18b This is an embodiment of the present invention. Figure 18a Enlarged view of point F.

[0053] Figure 19 This is a schematic diagram of the slider buckle structure in an embodiment of the present invention.

[0054] Figure 20 This is a schematic diagram of the groove and slider buckle structure in an embodiment of the present invention.

[0055] The attached figures are labeled as follows:

[0056] 1. Base; 101. Groove; 2. Liquid reservoir; 201. Inlet; 202. Outlet; 3. Piston; 4. Positioning rod; 5. Screw; 6. Hexagonal stud; 601. Snap-fit ​​structure; 7. Gear; 701. First limiting surface; 702. Second limiting surface; 8. First slider; 9. First spring; 10. First electrochromic alloy wire; 11. Second slider; 12. Second spring; 13. Second electrochromic alloy wire; 14. Locking structure; 15. Helical torsion spring; 16. Connecting locking structure; 17. Connecting structure; 18. Third slider; 19. Fourth slider; 1901. Slider snap-fit ​​structure; 20. Steel needle; 21. Guide tube. Detailed Implementation

[0057] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0058] It should be noted that the directional terms such as left, right, up, down, top, and bottom used in this embodiment are only relative concepts or are based on the normal use of the product, and should not be considered as restrictive.

[0059] This invention proposes a wearable, digital precision infusion pump for delivering injectable liquids. The pump can store the required liquid after assembly, maximizing its stability during transport. The pump drives gears by switching an energized alloy wire on and off; the number of energization cycles directly correlates to the rotation angle. The gear's tooth design and machining control the minimum infusion volume for each delivery, ensuring precise liquid delivery. A linkage with the needle insertion system connects the pump to the body. This digital precision infusion pump is small, lightweight, and low-cost, making it easy to carry and suitable for use as a patch-type precision drug delivery system, particularly promising for diabetes management. The pump requires outer packaging and is attached to the skin with medical tape, embodying its wearable nature. Its digital functionality lies in its ability to deliver the required liquid in precise, small-volume intervals. The principle behind controlling the minimum infusion volume is as follows: When the cross-sectional area of ​​the reservoir and the pitch of the hexagonal stud are fixed, the infusion volume per revolution of the gear is also fixed. Therefore, the minimum infusion volume is related to the number of teeth on the gear. The size of the gear and its dimensions (involving errors) indirectly affect the minimum infusion volume. Thus, the minimum infusion volume for each cycle is controlled through the design and manufacturing of the gear's tooth count.

[0060] like Figure 2-6 As shown, the precision injection pump proposed in this embodiment of the invention includes: a base 1, a liquid storage system, a control system, a needle insertion system, and a circuit system, all fixed to and connected to each other on the base 1. The liquid storage system, control system, and needle insertion system are interconnected. The liquid storage system is as follows... Figure 3 As shown, the control system is as follows Figure 4 As shown, the needle insertion system is as follows Figure 5 As shown, the base is as follows Figure 6As shown. Specifically, the liquid storage system includes a liquid reservoir 2 fixed on a base 1, with a liquid inlet / outlet control component inside the reservoir 2; the control system includes a gear 7 and a transmission component fixed on the base 1, and a sliding component in contact with the gear 7. The gear 7 is connected to both the liquid inlet / outlet control component and the needle insertion system, and the transmission component is connected to the sliding component; the control system drives the liquid inlet / outlet control component to move through the rotation of the gear 7, thereby controlling the delivery of liquid in the liquid storage system and controlling the movement of the needle insertion system to achieve needle insertion and withdrawal; the circuit system is connected to the transmission component for energizing or de-energizing it, thereby driving the gear 7 to rotate through the sliding component. The circuit system also includes a Bluetooth module or other radio module for receiving injection commands transmitted by an external system.

[0061] Once the precision injection pump is assembled, it will operate as follows: Figure 1 The precision injection pump control method shown controls the precision injection pump proposed in this embodiment of the invention:

[0062] S1. Liquid storage: After the precision injection pump is assembled, the liquid to be injected is injected into the reservoir 2. When the liquid in the reservoir 2 reaches a certain capacity, the mechanical latching structure locks and triggers the sensor to stop the liquid infusion into the reservoir.

[0063] S2. Needle insertion system introduction: When the reservoir in step S1 is full of liquid, the needle insertion system and the control system are connected through the locking structure 14. The control system controls the needle insertion system to insert the needle, specifically to deliver the needle into the human or animal body.

[0064] S3. Receiving Injection Command: The first step of this invention is completed after the needle insertion system is inserted into the body, as described in step S2. Subsequent steps are established after the first step. When liquid injection is required, the circuitry in the precision infusion pump receives an injection command transmitted from an external system. This injection command is received via a Bluetooth module or other radio module within the circuitry.

[0065] S4. Issuing a drive command: After the needle insertion system in step S2 is introduced into the body and the injection command is received in step S3, the circuit system in the precision injection pump will issue a drive command, which will calculate the volume of the liquid to be injected and convert it into the number of times the transmission components in the control system are energized, that is, the number of times the electrochromic alloy wire is energized.

[0066] S5. Execute the drive command: After the injection pump issues the injection command in step S4, the power supply and de-energize of the circuit system transmission components are controlled, specifically the power supply and de-energize of the electrochromic alloy wire, to precisely deliver the liquid.

[0067] The volume conversion principle is as follows: The volume of liquid injected by the first and / or second electrochromic alloy wires each time they are energized is constant. Therefore, the number of energization and de-energization cycles can be obtained by dividing the target injection volume by the injection volume per energization and de-energization cycle. For example, if the amount of liquid injected by the first or second electrochromic alloy wire each time is 0.5u, and a total of 20u needs to be injected, then the energization and de-energization cycles need to be 20u / 0.5u = 40 times.

[0068] In some preferred embodiments, the liquid storage system is as follows: Figures 7a-7f As shown, the reservoir 2 has a non-circular cross-sectional shape, designed to ensure that the piston 3 remains relatively stationary axially relative to the reservoir 2 when the gear 7 rotates. Furthermore, the volume of the reservoir 2 is designed to range from 0 μl to 999 ml. Specifically, when the reservoir 2 is designed to hold 3 ml, its main structure is a cylinder. More specifically, when the reservoir 2 has an elliptical cross-section, its major axis is 9 mm, its minor axis is 5 mm, and its effective height is 21.22 mm. In some embodiments, the reservoir 2 can also be designed with a base that is any non-circular cylindrical shape other than an ellipse.

[0069] Specifically, such as Figure 8 As shown, the bottom of the liquid reservoir 2 is provided with an inlet 201 and an outlet 202. The inlet 201 is used to store the liquid. The outlet 202 is used to precisely deliver the liquid. In some preferred embodiments, both the inlet 201 and the outlet 202 are sealed with rubber stoppers. Figure 8 The positions of the liquid inlet 201 and liquid outlet 202 shown are merely examples; the positions of the liquid inlet 201 and liquid outlet 202 can be set at any position on the bottom of the liquid reservoir 2. In this embodiment of the invention, as... Figure 8 As shown, when the liquid inlet 201 is located at the bottom of the liquid reservoir 2 or at the end of the short axis D of the liquid reservoir 2 cross-section, it facilitates the introduction of liquid. Preferably, when the liquid outlet is located at the bottom of the liquid reservoir 2, the liquid utilization efficiency in the liquid reservoir 2 is the highest. Preferably, as... Figure 14 As shown, the system's space utilization efficiency is maximized when the outlet is located on the major axis E of the reservoir 2's cross-section. More preferably, the utilization efficiency is maximized when the inlet and outlet coincide. When the precision syringe pump is injecting liquid into the reservoir 2, the conduit for outlet 202 is not connected to outlet 202; when the liquid injection is complete, the conduit for outlet 202 is connected to outlet 202. When the inlet 201 and outlet 202 coincide, the possibility of leakage is reduced, and the conduit connected to outlet 202 can be directly connected when the reservoir 2 is full of liquid.

[0070] In embodiments of the present invention, such as Figures 7a-7fAs shown, the liquid inlet / outlet control assembly includes a piston 3, a screw 5, and a hexagonal stud 6. The piston 3 is located inside the reservoir 2, and the screw 5 is fixedly connected to the surface of the piston 3. The end of the screw 5 away from the piston 3 is connected to the hexagonal stud 6, which is connected to a gear 7. One end of the reservoir 2 has an opening, and inside it is a piston 3 with a rubber ring. The piston 3 with the rubber ring can seal the reservoir 2, specifically sealing the opening of the reservoir 2. The piston 3 can move radially relative to the liquid; specifically, the piston 3 can move radially as liquid is injected or discharged. A screw 5 is fixed to the surface of the piston 3. Preferably, the entire structure is most stable when the screw 5 is on the central axis of the piston 3. In some embodiments, the pitch of the screw 5 can be designed according to accuracy requirements, ranging from 0.1mm to 5mm. The volume of liquid delivered by the screw in one revolution can be designed as needed, ranging from 0ml to 5ml. Specifically, once the cross-sectional shape of the reservoir 2 is fixed and the pitch of the hexagonal stud is determined, the volume delivered by the stud in one revolution will also be determined. More specifically, when a standard screw with a pitch of 0.35mm is used, and the cross-section of the reservoir 2 is designed to be elliptical with a major axis of 9mm and a minor axis of 5mm, the volume of liquid delivered by the screw 5 in one revolution is 49.48μl.

[0071] In some preferred embodiments, to make the radial movement of the piston 3 in the reservoir 2 more stable, the reservoir system also includes a positioning rod 4. Specifically, a positioning rod 4 is fixedly installed on the surface of the piston 3 away from the cavity of the reservoir to assist in positioning and prevent deviation during piston movement. The position of the positioning rod 4 can be any position of the piston 3. The greater the distance between the positioning rod 4 and the screw 5, the more stable the radial movement of the piston 3 in the reservoir 2. Specifically, the center of the positioning rod 4 is designed to be on the long axis of the piston, 7.5 mm away from the center of the piston. The screw 5 needs to be connected to its matching hexagonal stud 6. Specifically, the hexagonal stud 6 is designed to be a regular hexagon. The hexagonal stud 6 is connected to the gear 7. The inner wall of the gear 7 is a regular hexagon. The hexagonal stud 6 and the screw 5 are mutually fitted, and both have the same pitch. When the pitch of the hexagonal stud 6 is a standard thread of 0.35 mm, the distance between opposite sides of the regular hexagonal outer wall is 3 mm. There is a certain gap between the inner wall of gear 7 and hexagonal stud 6, with the gap ranging from 0mm to 0.5mm. This is to reduce frictional resistance when hexagonal stud 6 moves relative to gear 7 axially during liquid injection. Preferably, when the gap between hexagonal stud 6 and gear 7 is 0.2mm, it ensures low frictional resistance during liquid injection and minimizes errors in gear 7 rotation during liquid injection. The end of gear 7's inner wall away from the reservoir 2 is connected to hexagonal stud 6 via a special design. Specifically, the hexagonal stud 6 has a snap-fit ​​structure at its top. Figure 15 The image shown is a three-dimensional structural diagram of the snap-fit ​​structure at the top of the hexagonal stud 6. Figure 16 The diagram shows a three-dimensional cross-sectional view of the first and second limiting surfaces of gear 7. The snap-fit ​​structure can deform under stress; its special design aims to ensure that the hexagonal stud 6 and gear 7 remain relatively stationary. Specifically, when the liquid storage system is not yet filled with liquid... Figure 7a As shown, when the liquid storage system is injected with liquid, as Figure 7b As shown, when the injection reaches a certain level, and the snap-fit ​​structure 601 at the top of the hexagonal stud 6 abuts against the first limiting surface 701 of the gear 7, as... Figure 7c and Figure 7d As shown, the snap-fit ​​structure 601 begins to deform under stress, and liquid continues to be injected until the reservoir 2 is full, as... Figure 7e and Figure 7f As shown, the snap-fit ​​structure 601 at the top of the hexagonal stud 6 abuts against the second limiting surface 702 of the gear 7.

[0072] In this embodiment of the invention, the number of teeth on gear 7 can be selected according to the required precision, ranging from 7 to 120 teeth. Specifically, when the number of teeth is selected to be 50, a drive command is issued to inject liquid. When the cross-section of reservoir 2 is designed to be elliptical with a major diameter of 9 mm and a minor diameter of 5 mm, and a standard screw 5 with a pitch of 0.35 mm is used, the precision injection pump has a precision of 0.4948 μL / cycle.

[0073] In this embodiment of the invention, the transmission assembly includes a first spring 9, a second spring 12, a first electrochromic alloy wire 10, and a second electrochromic alloy wire 13. One end of each of the first spring 9, the second spring 12, the first electrochromic alloy wire 10, and the second electrochromic alloy wire 13 is fixed to the base 1. The sliding assembly includes a first slider 8 and a second slider 11. One end of each slider 8 and the second slider 11 contacts the gear 7. The first spring 9 is sleeved on the first electrochromic alloy wire 10, and the other ends of the first spring 9 and the first electrochromic alloy wire 10 are connected to the other end of the first slider 8. The second spring 12 is sleeved on the second electrochromic alloy wire 13, and the other ends of the second spring 12 and the second electrochromic alloy wire 13 are connected to the other end of the second slider 11. Both ends of the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 are connected to the circuit system. The main component of the circuit system is a circuit board, which is connected to the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 of the control system.

[0074] Gear 7 requires external force to operate. In this embodiment, a first slider 8 and a second slider 11 are used to push gear 7. The tops of the first slider 8 and the second slider 11 have a certain angle, ranging from 15° to 75°. In step S4 of this embodiment, liquid injection is achieved by switching the first energized variable alloy wire 10 on and off, which drives the first slider 8, and the second energized variable alloy wire 13 on and off, which drives the second slider 11, further pushing gear 7. The ends of the first slider 8 and the second slider 11 are respectively connected to a spring to form a small system. The first slider 8 and the second slider 11 have a certain phase difference, ranging from 120° to 240°. This ensures that they can continuously push gear 7 to rotate. Preferably, when the phase difference between the first slider 8 and the second slider 11 is 180°, it can be ensured that the volume of liquid delivered each time the energized variable alloy wire is energized is the same, that is, it ensures that the volume of liquid delivered when the first energized variable alloy wire 10 and the second energized variable alloy wire 13 are energized is the same.

[0075] There are two ways to drive gear 7 to rotate, as detailed below:

[0076] The first method of driving gear rotation: The gear is directly driven to rotate by an electrically conductive alloy wire. Specifically, the initial state of the control system is as follows: Figure 9a As shown, the first slider 8 is connected to the root of the gear 7, and the second slider 11 is connected to the gear 7 at halfway point on the tooth surface. When the circuit system energizes the first energized variable alloy wire 10, as shown... Figure 9b As shown, the first energized variable alloy wire 10 contracts, causing the first slider 8 to slide along the track towards disengagement from the gear 7. The second spring 12 returns from its mid-compression state to its longest compression state. When it touches the gear 7, it pushes the second slider 11, causing the gear 7 to rotate until the second slider 11 contacts the root of the gear 7's teeth. At this time, the first spring 9 is in its shortest compression state. When the circuit system de-energizes the first energized variable alloy wire 10, as... Figure 9c As shown, the first spring 9 returns from its shortest compression state to its mid-range compression state (i.e., its original length), causing the first slider 8 to reach halfway down the tooth surface of the gear 7. A single discharge of the first energized variable alloy wire 10 completes the rotation of 0.5 teeth of the gear 7.

[0077] In this embodiment of the invention, the number of rotations of gear 7 depends on the volume of the liquid to be transported, the design of the reservoir 2, the design of the screw pitch 5, and other data, with a range of 0-200 rotations. Similarly, when the circuit system discharges the second slider 11, the second spring 12, and the second electrochromic alloy wire 13, the remaining 0.5 teeth of gear 7 are moved. Specifically, when the circuit system energizes the second electrochromic alloy wire 13, such as... Figure 9d As shown, the second electrochromic alloy wire 13 contracts, causing the second slider 11 to slide towards disengagement from the gear 7. When the first slider 8 contacts the gear 7, it pushes the gear 7 to rotate, and the second spring 12 is in its shortest compression state. When the circuit system de-energizes the second electrochromic alloy wire 13, the second spring 12 returns from its shortest compression state to its mid-range compression state (i.e., its original length), causing the second slider 11 to disengage from the gear 7; the gear 7 completes the rotation of the remaining 0.5 teeth. This example demonstrates how the injection of a precision syringe pump can be achieved by sequentially switching the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 on and off.

[0078] The second method of driving gear rotation involves storing energy in a spring via an electrochromic alloy wire. The spring then pushes a slider, thereby rotating the gear. Specifically, the contact point between the first slider 8, the second slider 11, and the gear 7 is at the halfway point of the tooth surface. When the circuit system energizes the first electrochromic alloy wire 10, it drives the first slider 8 to slide along the track towards the gear 7. At this time, the first spring 9 begins to compress. When the first slider 8 and the gear 7 disengage (i.e., no longer contact), the energy stored in the second spring 12 begins to be released, pushing the gear 7 to rotate 0.5 teeth. When the circuit system de-energizes the first electrochromic alloy wire 10, the first spring 9 returns from its shortest compression state to its mid-range compression state (i.e., its original length), pushing the first slider 8 to slide along the track towards the gear 7 until it contacts the gear surface. Since the second slider 11 and the gear 7 are in contact at this time, and the gear 7 is in the off state, the first slider 8 will stop moving. The remaining energy stored in the first spring 9 will be released when the second electrochromic alloy wire 13 is energized and the second slider 11 disengages from the gear 7. Similarly, the circuit system completes the movement of the other 0.5 teeth of the gear 7 by performing a single on-off cycle on the second slider 11, the second spring 12, and the second electrochromic alloy wire 13. Specifically, when the circuit system energizes the second electrochromic alloy wire 13, the second electrochromic alloy wire 13 drives the second slider 11 to slide along the track towards the direction of disengagement from the gear 7, and the second spring 12 begins to compress; when the second slider 11 disengages from the gear 7, the energy stored in the first spring 9 begins to be released, pushing the gear 7 to rotate another 0.5 teeth; when the circuit system de-energizes the second electrochromic alloy wire 13, the second spring 12 recovers from the shortest compression state to the middle compression state (i.e., the original length), pushing the second slider 11 to slide along the track towards the gear 7 until it contacts the gear 7, specifically, contacts the gear surface; the first slider 8 contacts the gear surface of the gear 7, the gear 7 is in the cut-off state, the second slider 11 stops moving, and the remaining energy stored in the second spring 12 will be released when the first electrochromic alloy wire 10 is energized and the first slider 8 disengages from the gear 7, completing the movement of the other 0.5 teeth of the gear 7. This example demonstrates how a precision injection pump can deliver fluid by sequentially switching the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 on and off.

[0079] In this embodiment of the invention, the needle insertion system includes a locking structure 14, a helical torsion spring 15 fixed on a base 1, a connecting locking structure 16, a connecting structure 17, a third slider 18, a fourth slider 19, a steel needle 20, and a conduit 21. The locking structure 14 is connected to both the gear 7 and the connecting locking structure 16. The connecting locking structure 16 is connected to both the helical torsion spring 15 and the connecting structure 17. The third slider 18 and the fourth slider 19 are on the same track, and the third slider 18 is connected to both the connecting structure 17 and the steel needle 20. Specifically, the driving force of this needle insertion system is a helical torsion spring 15, which is connected to the third slider 18 via the connecting locking structure 16 and the connecting structure 17. The third slider 18 fixes the steel needle 20, and the fourth slider 19 connects to the conduit 21. One end of the conduit 21 is connected to the outlet 202 of the reservoir 2. The connecting locking structure 16 is connected to the gear 7 via the locking structure 14 that connects the gear and the spring.

[0080] The initial state of the needle insertion system is as follows: Figure 10a As shown, the images of gear 7, locking structure 14, and the part connecting locking structure 16 at this time are as follows: Figure 10b As shown. When gear 7 rotates, as... Figure 10c As shown, the locking structure 14, which drives the connecting gear and spring, rotates, causing the helical torsion spring 15 to release. The state of the forward needle system after the helical torsion spring 15 releases is as follows. Figures 17a to 17b As shown, the state of the needle insertion system after the helical torsion spring 15 is released is as follows: Figures 18a to 18b As shown. The release of the helical torsion spring 15 causes the connecting locking structure 16 to rotate, thereby pushing the third slider 18 and the fourth slider 19 to slide along the same track, thus pushing the steel needle 20 to pierce the skin. After piercing the skin, the steel needle 20 is driven back by the third slider, specifically as follows... Figure 10d As shown, the conduit 21 will remain inside the body due to the special design of the tip of the fourth slider 19. Specifically, a slider latching structure 1901 is designed at the top of the fourth slider 19, and a groove 101 is provided on the track of the base. When the fourth slider 19 reaches the groove 101, the slider latching structure 1901 engages with the groove 101 to fix the fourth slider 19. A schematic diagram of the slider latching structure 1901 is shown below. Figure 19 As shown in the diagram, the groove 101 and the slider snap-fit ​​structure 1901 are illustrated in the figure below. Figure 20 As shown.

[0081] Example:

[0082] This embodiment proposes a digital precision injection pump, which mainly comprises four parts: a liquid storage system, a control system, a needle insertion system, and a circuit system. The liquid storage system, control system, and needle insertion system are interconnected. The circuit system mainly consists of a circuit board and an energized variable alloy wire connected to the control system. Specifically, it includes the following components:

[0083] Liquid storage system: The main part is the liquid storage tank 2, such as Figures 7a-7f and Figure 8 As shown, it has an inlet 201 and an outlet 202. One end of the reservoir 2 is open, and a piston 3 is connected inside. A screw 5 and a positioning rod 4 are fixed on the piston 3. The screw 5 is connected to a hexagonal stud 6. The other end of the hexagonal stud 6 is designed with a mechanical snap-fit ​​structure 601.

[0084] Control system: such as Figures 9a-9d As shown, its main body consists of a gear 7 and a slider, the slider including a first slider 8 and a second slider 11. Figure 7c-7f As shown, gear 7 is connected to hexagonal stud 6 in the liquid storage system. When hexagonal stud 6 reaches the designated position, the two are in a relatively stationary state. Specifically, during the liquid injection process of the liquid storage system, when the liquid is injected to a certain extent, and the snap-fit ​​structure 601 at the top of the hexagonal stud 6 abuts against the first limiting surface 701 of the gear, as... Figure 7c and Figure 7d As shown, the snap-fit ​​structure 601 begins to deform, and liquid continues to be injected until the reservoir 2 is full, as... Figure 7e and Figure 7f As shown, the snap-fit ​​structure 601 at the top of the hexagonal stud 6 abuts against the second limiting surface 702 of the gear. (As shown...) Figures 9a-9d As shown, the control system has two sliders, specifically a first slider 8 and a second slider 11. Their tips are at a certain angle and contact a tooth of the gear 7, allowing for relative movement. Both sliders move in their respective tracks with a 180° phase difference. The ends of sliders 8 and 11 are connected to a first spring 9 and a second spring 12, respectively, with the other ends of springs 9 and 12 fixed to the base. Specifically, the ends of sliders 8 and 11 are connected to one end of a first electrochromic alloy wire 10 and a second electrochromic alloy wire 13, respectively. The other ends of these wires are fixed to the base, and their relative positions on the base can be changed, allowing them to be stretched and connected to the circuit. When the first electrochromic alloy wire 10 is energized and deformed, it causes the first slider 8 to move linearly, and the gear 7 to rotate half a turn. When the first electrochromic alloy wire 10 is de-energized and the second electrochromic alloy wire 13 is energized, it drives the second slider 11 to move linearly, causing the gear 7 to rotate half a turn. By energizing and de-energizing the first and second electrochromic alloy wires 10 and 13, the gear 7 is controlled to rotate. The rotation of the gear 7 drives the hexagonal stud 6 and the screw 5 to move relative to each other, causing the piston 3 in the liquid storage system to pump the liquid out of the liquid reservoir 2.

[0085] Needle insertion system: such as Figures 10a-10dAs shown, the main body of the needle insertion system consists of a helical torsion spring 15 and two sliders. Specifically, the two sliders are a third slider 18 and a fourth slider 19, which are on the same track. The third slider 18 is closer to the helical torsion spring 15 and is connected to a steel needle 20 for piercing the skin. The fourth slider 19 is further away from the helical torsion spring 15 and is connected to an infusion tubing 21 extending from the outlet of the reservoir 2. The helical torsion spring 15 is connected to the third slider 18 via two connectors, specifically a locking structure 16 and a connecting structure 17. The locking structure 14 is rotatable; one end of its normal direction is a portion with the same module as gear 7, and the other end is a sliding surface with a certain angle. The entire system is connected to gear 7 via custom-designed parts. Initially, the needle insertion system is as follows... Figure 10a and Figure 10b As shown, the helical torsion spring 15 is rotated from its initial position to a designated position, and a custom part is used to partially fix it. The third slider 18 and the fourth slider 19 are in their initial positions. The first working state of the needle feeding system upon startup is as follows: Figure 10c As shown, gear 7 drives the custom component to rotate. When it rotates a certain number of teeth, the custom structure releases the helical torsion spring 15. The helical torsion spring 15 drives the third slider 18 to move on the track, and simultaneously, the third slider 18 pushes the fourth slider 19 to perform the same movement. Since the third slider 18 is connected to a steel needle, when the skin is pierced, the infusion catheter 21 connected to the fourth slider 19 is simultaneously inserted into the skin. When the third slider 18 and the fourth slider 19 move to their furthest point, the needle insertion system enters the second working state, as shown... Figure 10d As shown, the spiral torsion spring 15 continues to rotate, causing the third slider 18 to move in the opposite direction, removing the steel needle 20 from the body. At the same time, the fourth slider 19 is jammed and stops moving, leaving the infusion catheter 21 in the body.

[0086] The precision injection pump proposed in this embodiment of the invention can achieve an accuracy of 0.5 μl / injection and deliver a liquid volume of 900 μl per hour.

[0087] like Figure 2 As shown, the base 1 serves to fix and support other parts, and its design varies according to the dimensions of these other parts. These other parts include a reservoir, positioning rod, hexagonal stud, gear, first slider, first spring, first electrochromic alloy wire, second slider, second spring, second electrochromic alloy wire, locking structure, helical torsion spring, connecting locking structure, connecting structure, third slider, and fourth slider.

[0088] The liquid injection process of the precision injection pump proposed in this embodiment of the invention is as follows: Figures 7a-7fAs shown, the components include: base 1, reservoir 2, piston 3, positioning rod 4, screw 5, hexagonal stud 6, and gear 7. Reservoir 2 is fixed to base 1. Piston 3 is located inside reservoir 2. One end of the positioning rod is fixed to the piston surface. One end of screw 5 is fixed to the piston surface, and the other end is connected to hexagonal stud 6. Gear 7 is fixed to base 1, and its through-hole is connected to hexagonal stud 6.

[0089] Both the outlet 202 and inlet 201 of the liquid reservoir 2 are sealed with rubber stoppers, and a cap is fitted on top. In this embodiment, the cross-sectional shape of the liquid reservoir 2 is designed to be elliptical to prevent the piston from undergoing relative circular motion during operation. When preparing to inject liquid into the liquid reservoir 2, refer to... Figure 7a When reservoir 2 is empty, the piston is at the bottom of reservoir 2. Liquid is injected into reservoir 2 via an external pump through inlet 201. When injecting liquid, refer to... Figure 7b The liquid pushes piston 3 upward, causing hexagonal stud 6 to move along the track axis of gear 7. When the liquid in reservoir 2 is about to reach a predetermined volume, refer to... Figure 7c and Figure 7d The latching structure 601 at the top of the hexagonal stud 6 begins to bear force, specifically, the latching structure 601 abuts against the first limiting surface 701 of the gear, and the latching structure 601 begins to work. When the liquid in the reservoir 2 reaches a predetermined volume, refer to... Figure 7e and Figure 7f The snap-fit ​​structure 601 at the top of the hexagonal stud 6 abuts against the second limiting surface 702 of the gear, and the snap-fit ​​structure 601 completes its work and stops injecting liquid. At this time, the liquid storage system has 1 degree of freedom, specifically the rotation of the gear 7.

[0090] Reference Figure 7c-7f The hexagonal stud 6 features a special design at its top: a snap-fit ​​structure 601. Three snap-fit ​​structures 601 are evenly distributed in a ring at the top of the hexagonal stud 6, capable of deformation under stress. The first limiting surface 701 and the second limiting surface 702 are two protruding surfaces from the inner wall of the gear 7. The angle between the second limiting surface 702 and the gear 7 is larger than that between the first limiting surface 701 and the second limiting surface 702. There is a surface perpendicular to the inner wall of the gear 7 between the first limiting surface 701 and the second limiting surface 702. When the hexagonal stud 6 moves along the inner wall of the gear 7 towards the snap-fit ​​structure 601, it first contacts the second limiting surface 702, at which point the snap-fit ​​structure 601 begins to deform. When the snap-fit ​​structure 601 contacts the second limiting surface 702, the snap-fit ​​structure 601 of the hexagonal stud 6 experiences a tangential force due to deformation, but the movement of the hexagonal stud 6 is stopped by the second limiting surface 702. Therefore, the hexagonal stud 6 is locked at this point, and the entire liquid storage system has only one degree of freedom, namely the movement of the gear 7.

[0091] A schematic diagram of the working process of the control system of the precision injection pump is shown below. Figures 9a-9dThis includes: gear 7, first slider 8, first spring 9, first electrochromic alloy wire 10, second slider 11, second spring 12, and second electrochromic alloy wire 13. Gear 7 is fixed in position on base 1 and can only rotate. One end of the first spring 9 and the second spring 12 is fixed to base 1, and the other end is connected to the first slider 8 and the second slider 11, respectively. One end of the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 is fixed to base 1, and the other end is connected to the first slider 8 and the second slider 11, respectively. The two ends of the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 are respectively connected to the corresponding parts of the circuit system, and their contraction and restoration are controlled by the energization and de-energization of the circuit system. Gear 7 of the control system and hexagonal stud 6 of the liquid storage system are relatively stationary after the liquid storage system has completed liquid storage. When gear 7 rotates, it drives screw 5 and hexagonal stud 6 to rotate, causing piston 3 to move and push the liquid in the liquid reservoir 2 out of the outlet 202.

[0092] The ends of the first spring 9 and the second spring 12 are fixed to the base 1. The first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 have the characteristic of contraction upon energization. Refer to [the following text is incomplete and requires further context:] When there is no need for liquid infusion, refer to [the following text is incomplete and requires further context:] Figure 9a Both the first slider 8 and the second slider 11 are in contact with the gear 7. Specifically, the first slider 8 is connected to the root of the gear 7 teeth, and the second slider 11 is connected to the halfway point of the gear 7 teeth. The first slider 8 acts as a stopper for the movement of the gear 7, while the second slider 11 exerts a rotational force on the gear 7. When there is a need for infusion, the command is transmitted through the control system to the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13. When the first electrochromic alloy wire 10 is energized, it contracts, as... Figure 9b As shown, the first electrochromic alloy wire 10 contracts, causing the first slider 8 to disengage from the gear 7. When the first slider 8 and the gear 7 are not in contact, the second spring 12 returns from its mid-compression state to its longest compression state, thus pushing the second slider 11 to move linearly. When it touches the gear 7, it pushes the second slider 11, causing the gear 7 to rotate, until the second slider 11 contacts the root of the gear 7's teeth. Specifically, it pushes the gear to rotate by 0.5 teeth. The first spring 9 is at its shortest compression state at this time. Figure 9c As shown, when the first energized variable alloy wire 10 is de-energized, the first spring 9, trending from its shortest compression state to its mid-range compression state (i.e., its original length), drives the first slider 8 to move along the track until it contacts the tooth surface of the gear 7. Specifically, in this embodiment, the contact point between the first slider 8 and the second slider 11 and the gear 7 is at 1 / 2 of the tooth surface, to ensure that the amount injected each time is the same. By energizing and de-energizing the first energized variable alloy wire 10, one liquid injection is completed. Similarly, as... Figure 9dAs shown, when the second electrochromic alloy wire 13 is energized and de-energized, one liquid injection is completed. By energizing and de-energizing the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13, liquid injection into the reservoir 2 can be completed. When the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 are continuously energized and de-energized, continuous liquid injection can be achieved.

[0093] The needle insertion system of the precision injection pump in this embodiment of the invention is as follows: Figures 10a-10d As shown. It includes: a locking structure 14 connecting the gear 7 and the helical torsion spring 15, the helical torsion spring 15, a connecting locking structure 16, a connecting structure 17, a third slider 18, a fourth slider 19, a steel needle 20, and a guide tube 21, etc. The function of the helical torsion spring 15 is to provide power to the needle injected into the human body. One end of the helical torsion spring 15 is fixed to the base 1, specifically axially fixed to the base 1, and the other end is connected to the connecting locking structure 16. The other end of the connecting locking structure 16 is connected to the third slider 18. The third slider 18 and the fourth slider 19 share a track. The third slider 18 connects to a section of the steel needle 20, and the fourth slider 19 fixes the guide tube 21. One end of the locking structure 14 connecting the gear 7 and the helical torsion spring 15 has two teeth with the same module as the gear 7, and the other end has a protrusion for connecting and cutting off the connecting locking structure 16. The function of the locking structure 14 connecting the gear 7 and the spring is to connect the control system and the needle insertion system.

[0094] The needle insertion system comes into play when a precision infusion pump needs to be connected to the human body. (See reference...) Figure 10a and Figure 10b When gear 7 rotates, it drives the locking structure 14 connecting gear 7 and helical torsion spring 15 to rotate. The other end of the locking structure 14 connecting gear 7 and helical torsion spring 15 is connected to the connecting locking structure 16. When the locking structure 14 connecting gear 7 and helical torsion spring 15 disengages from the connecting locking structure 16, as... Figure 10c As shown, the helical torsion spring 15 drives the connecting locking structure 16 to rotate, thereby pushing the third slider 18 and the fourth slider 19 to move along the track. The third slider 18 is connected to the steel needle 20 for piercing the skin; the fourth slider 19 is connected to the catheter 21 for delivering liquid. Once the steel needle 20 pierces the skin to the designated location, refer to... Figure 10c At this point, the third slider 18 and the fourth slider 19 have moved to their furthest points. When the helical torsion spring 15 continues to rotate and returns to its original length, it drives the connecting locking structure 16, which in turn drives the connecting structure 17, which in turn drives the third slider 18 to move in the opposite direction along the track, causing the steel needle 20 to detach from the human body. (Refer to...) Figure 10d The third slider 18 and the steel needle 20 will return to their initial positions.

[0095] In some preferred embodiments, the reservoir 2 is shaped as an elliptical cylindrical shell with a protruding bottom, the major axis of the ellipse on the inner wall of the cross-section being 8mm, the minor axis 6mm, and the height 16mm. The screw 5 has a pitch of 0.35mm. The gear has 35 teeth. The effective length of the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13 is 20mm, the current is 0.32A, and the voltage is 1V.

[0096] Experimental Example 1:

[0097] Reference Figures 1-10d The structure, assembly, and liquid delivery steps of a precision syringe pump are described. A precision syringe pump is used to deliver vegetable oil (density 0.92 g / ml). The operating steps are as follows: First, the vegetable oil is introduced into reservoir 2. The program is manually set to control the energization and de-energization of the electrochromic alloy wire. The outlet tube is connected to a watch glass placed on a 0.001 g / ml balance. At the start of the measurement, to reduce errors such as surface phenomena and capillary effects, a certain volume of vegetable oil is placed in the watch glass, and the balance is zeroed. The number of times the electrochromic alloy wire is energized and de-energized and the corresponding 0.001 g / ml balance reading are recorded. The relationship between the number of times the electrochromic alloy wire is energized and de-energized and the balance reading is as follows: Figure 11 As shown. Where x represents the number of times the electrochromic alloy wire is energized, y represents the balance reading, and R... 2 This is the linear correlation coefficient. In the test, the theoretical weight of the vegetable oil was 24.3 mg after 35 cycles of electrolysis, while in actual measurements, the average weight after 35 cycles was 23.4 mg, with an error of 3.70%. After 420 cycles of electrolysis, the theoretical balance reading was 291.6 mg, while the actual reading was 280.4 mg, with an error of 3.84%.

[0098] Experimental Example 2:

[0099] Reference Figures 1-10d This paper describes the structure, assembly, and liquid delivery steps of a precision infusion pump. Insulin was delivered using this pump. The concentration of insulin was measured by measuring ultraviolet absorption. A commercial insulin solution (400u / 10ml) was purchased. A standard curve was first plotted to correlate insulin solution concentration with absorbance. All dilution solutions used in the experiment were NaH₂PO₃ buffer solution at pH 7.35. The resulting standard curve is shown below. Figure 12 As shown in the figure. The horizontal axis x represents the insulin concentration, and the vertical axis y represents the absorbance value, R... 2Correlation coefficient. Pretreatment is required before using the high-precision infusion pump of this invention to deliver insulin solution. The purchased insulin solution has a concentration of 400 u / 10 ml. 2 ml is injected into the precision infusion pump. A 0.1 u / ml insulin solution is prepared as the stock solution. The outlet of the precision infusion pump's tubing 21 is placed in the stock solution for 24 hours. Experiments are conducted by applying current to the first electrochromic alloy wire 10 and the second electrochromic alloy wire 13, measuring the total number of energizations and the ultraviolet absorption intensity of the stock solution, and plotting the results. The plotting results are shown below. Figure 13 As shown in the figure. The horizontal axis x represents the number of times the electrochromic alloy wire is energized, and the vertical axis represents the amount of insulin delivered using absorption intensity. R 2 This is the correlation coefficient. In this experimental example, the average insulin delivery per 70 cycles was 2.022 units, compared to the theoretical value of 2.111 units, resulting in an error of 4.21%. The main reason for the relatively large error in this example was random error. The main causes of random error were uneven stirring of the mother liquor during each measurement, deviations in the liquid sampling position, incomplete transfer of the measurement liquid to the mother liquor, and instability in the system setup leading to some liquid from the precision injection pump being squeezed into the mother liquor in the early stages of the experiment.

[0100] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, several equivalent substitutions or obvious modifications can be made without departing from the concept of the present invention, and all such modifications, achieving the same performance or purpose, should be considered within the scope of protection of the present invention.

Claims

1. A precision injection pump, characterized in that, include: The base (1), a liquid storage system, a control system and a needle insertion system fixed on the base (1) and interconnected with each other, and a circuit system; The liquid storage system includes a liquid reservoir (2) fixed on the base (1), and the liquid reservoir (2) is provided with a liquid inlet and outlet control component. The control system includes a gear (7) and a transmission assembly fixed on the base (1), and a sliding assembly in contact with the gear (7). The gear (7) is connected to the liquid inlet / outlet control assembly and the needle insertion system respectively. The transmission assembly is connected to the sliding assembly. The control system drives the liquid inlet / outlet control assembly to move by rotating the gear (7), thereby controlling the delivery of liquid in the liquid storage system and controlling the movement of the needle insertion system to realize needle insertion and needle withdrawal. The circuit system is connected to the transmission component and is used to energize or de-energize it, thereby driving the gear (7) to rotate through the sliding component.

2. The precision injection pump as described in claim 1, characterized in that, The needle insertion system includes a locking structure (14), a helical torsion spring (15) fixed on the base (1), a connecting locking structure (16), a connecting structure (17), a third slider (18), a fourth slider (19), a steel needle (20), and a guide tube (21). The locking structure (14) is connected to the gear (7) and the connecting locking structure (16) respectively. The connecting locking structure (16) is connected to the helical torsion spring (15) and the connecting structure (17) respectively. The third slider (18) and the fourth slider (19) are on the same track. The third slider (18) is connected to the connecting structure (17) and the steel needle (20) respectively. The fourth slider (19) is connected to the guide tube (21). By rotating the gear (7), the helical torsion spring (15) drives the connecting locking structure (16) to rotate, thereby pushing the third slider (18) and the fourth slider (19) to move along the same track.

3. The precision injection pump as described in claim 1, characterized in that, The transmission assembly includes a first spring (9), a second spring (12), a first electrochromic alloy wire (10), and a second electrochromic alloy wire (13), one end of each of the first spring (9), the second spring (12), the first electrochromic alloy wire (10), and the second electrochromic alloy wire (13) being fixed to the base (1); the sliding assembly includes a first slider (8) and a second slider (11), one end of each of the first slider (8) and the second slider (11) being in contact with the gear (7); the first spring (9) The first spring (9) and the other end of the first electrochromic alloy wire (10) are respectively connected to the other end of the first slider (8). The second spring (12) is sleeved on the second electrochromic alloy wire (13). The other ends of the second spring (12) and the second electrochromic alloy wire (13) are respectively connected to the other end of the second slider (11). Both ends of the first electrochromic alloy wire (10) and the second electrochromic alloy wire (13) are connected to the circuit system.

4. The precision injection pump as described in claim 3, characterized in that, The first slider (8) is connected to the root of the gear (7), and the second slider (11) is connected to the halfway point of the gear (7). When the circuit system energizes the first electrochromic alloy wire (10), the first electrochromic alloy wire (10) contracts, causing the first slider (8) to slide in the direction of disengaging from the gear (7). The second spring (12) returns from the mid-range compression state to the longest compression state, pushing the second slider (11) to make the gear (7) rotate until the second slider (11) contacts the root of the gear (7), at which point the first spring (9) is in the shortest compression state. When the circuit system de-energizes the first electrochromic alloy wire (10), the first spring (9) returns to the mid-range compression state, causing the first slider (8) to reach the halfway point of the gear (7). The gear (7) completes a 0.5 tooth rotation. When the circuit system energizes the second electrochromic alloy wire (13), the second electrochromic alloy wire (13) contracts, causing the second slider (11) to slide towards the disengagement gear (7). When the first slider (8) contacts the gear (7), it pushes the gear (7) to rotate, and the second spring (12) is in its shortest compression state. When the circuit system de-energizes the second electrochromic alloy wire (13), the second spring (12) returns from its shortest compression state to its medium compression state, causing the second slider (11) to slide towards the gear (7) until it contacts the gear (7). The gear (7) completes another 0.5 teeth of rotation.

5. The precision injection pump as described in claim 3, characterized in that, The contact point between the first slider (8), the second slider (11), and the gear (7) is at half the tooth surface. When the circuit system energizes the first electrochromic alloy wire (10), the first electrochromic alloy wire (10) drives the first slider (8) to slide in the direction of disengaging from the gear (7), and the first spring (9) begins to compress. When the first slider (8) and the gear (7) disengage, the energy stored in the second spring (12) begins to be released, pushing the gear (7) to rotate 0.5 teeth. When the circuit system... When the first electrochromic alloy wire (10) is de-energized, the first spring (9) returns from its shortest compression state to its medium compression state, pushing the first slider (8) to slide along the track toward the gear (7) until it contacts the gear; the second slider (11) contacts the gear (7), the gear (7) is in the cut-off state, the first slider (8) stops moving, and the remaining energy stored in the first spring (9) will be released when the second electrochromic alloy wire (13) is energized and the second slider (11) disengages from the gear (7); When the circuit system energizes the second electrochromic alloy wire (13), the second electrochromic alloy wire (13) drives the second slider (11) to slide along the track toward the disengagement gear (7), and the second spring (12) begins to compress; when the second slider (11) disengages from the gear (7), the energy stored in the first spring (9) begins to be released, pushing the gear (7) to rotate another 0.5 teeth; when the circuit system de-energizes the second electrochromic alloy wire (13), the second spring (12) recovers from the shortest compression state to the medium compression state, pushing the second slider (11) to slide along the track toward the gear (7) until it contacts the gear (7); the first slider (8) contacts the gear (7), the gear (7) is in the cut-off state, the second slider (11) stops moving, and the remaining energy stored in the second spring (12) will be released when the first electrochromic alloy wire (10) is energized and the first slider (8) disengages from the gear (7).

6. The precision injection pump as described in claim 1, characterized in that, The liquid inlet / outlet control assembly includes a piston (3), a screw (5), and a hexagonal stud (6). The piston (3) is located inside the reservoir (2). The screw (5) is fixedly connected to the surface of the piston (3). The end of the screw (5) away from the piston (3) is connected to the hexagonal stud (6). The hexagonal stud (6) is connected to the gear (7).

7. The precision injection pump as described in claim 6, characterized in that, The screw (5) has a pitch of 0.1mm-5mm, and the volume of liquid transported by the screw (5) in one rotation is 0ml-5ml; the top of the hexagonal stud (6) is provided with a snap-fit ​​structure, which can deform under force, so that the hexagonal stud (6) and the gear (7) remain relatively stationary; there is a gap of 0mm-0.5mm between the inner wall of the hexagonal stud (6) and the gear (7).

8. The precision injection pump as described in claim 6, characterized in that, The liquid reservoir (2) has an inlet and an outlet at its bottom, both of which are sealed with rubber stoppers. The liquid reservoir (2) has a non-circular cross-sectional shape. One end of the liquid reservoir (2) has an opening, and the piston (3) has a rubber ring to seal the opening. The piston (3) can move radially as liquid is injected or discharged. The liquid storage system also includes a positioning rod (4), which is fixedly connected to the surface of the piston (3).

9. The precision injection pump as described in claim 3, characterized in that, The phase difference between the first slider (8) and the second slider (11) is 120°-240°.

10. A precision injection pump control method, based on the precision injection pump as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Liquid storage: After the precision injection pump is assembled, the liquid to be injected is injected into the reservoir. S2. Needle insertion system introduction: Connect the needle insertion system and the control system, and control the needle insertion system to perform needle insertion through the control system; S3. Receiving injection command: After the needle insertion system inserts the needle, when liquid injection is required, the circuit system receives the injection command emitted from the outside. S4. Issue drive command: The circuit system issues a drive command to convert the volume of liquid to be injected into the number of times the transmission component in the control system is energized. S5. Execute drive command: The circuit system controls the power on and power off of the transmission component to precisely transport the liquid.

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