Piston movement system for continuous microdosing device and method of operation

Abstract

This invention provides a piston motion system and operating method for a continuous micro-dose delivery device. The system includes a power-release device releasing a specified piston stroke under the action of a control device. The power-release device outputs a rotational torque to drive the piston body of the piston pusher device to move along a specified direction for the specified piston stroke. Sufficient drug solution is added to the drug storage device. The control device receives an externally input injection command or injection program. The control device initiates control of the power-release device to release the specified piston stroke, and the power-release device outputs a rotational torque to drive the piston body of the piston pusher device to move along a specified direction for the specified piston stroke. By driving the piston through the output rotational torque, the required number of pulses can be calculated based on the required infusion dose or piston movement distance. The control device precisely controls the power-release device to release the specified piston stroke, which helps improve the accuracy of drug delivery. Furthermore, the system is simple in structure and low in cost.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more specifically, to a piston motion system and its working method for a continuous micro-dose delivery device. Background Technology

[0002] Continuous dosing refers to administering a drug continuously every day to maintain an effective blood concentration. In current clinical practice, continuous dosing is frequently used in treatments such as endocrinology and analgesia.

[0003] Taking the treatment of diabetes as an example, there are currently two main methods for the treatment and control of diabetes: one is conventional treatment, which involves injecting insulin 1-2 times a day and monitoring blood glucose 1-2 times a day; the other is intensive treatment, which involves monitoring blood glucose multiple times a day and continuously infusing insulin in a manner that mimics the way pancreatic islet cells secrete insulin, in order to bring blood glucose as close to normal levels as possible. This method is mostly achieved using an insulin pump.

[0004] A Chinese patent application with publication number CN209984717U discloses a safe automatic insulin pen, comprising an insulin cartridge, a needle, a cartridge housing, an injection unit, a control unit, and a push rod unit for removing the needle. The injection unit includes an injection housing, a lead screw and nut assembly, a piston pusher, and a first base for mounting a nut to the lead screw and nut assembly, the outer ring of which is provided with gear teeth. The control unit includes a control housing, a motor, a motor gear, and a second base for mounting the motor gear, the outer ring of which is provided with gear teeth, the gear teeth meshing with the gear teeth on the nut of the lead screw and nut assembly. The push rod unit is disposed outside the cartridge housing.

[0005] Existing insulin pens use an electric motor as a power source to inject the drug solution. They have a complex structure, high cost, and low quantitative injection accuracy, and there are areas for improvement. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a piston motion system and its operating method for a continuous micro-dose delivery device.

[0007] According to the present invention, a piston motion system for a continuous micro-dose delivery device includes a piston push rod device, a power storage device, a power storage release device, and a control device; under the action of the control device, the power storage release device releases a specified piston stroke, and the power storage device outputs a rotational torque to drive the piston body of the piston push rod device to move along a specified direction for a specified piston stroke.

[0008] Preferably, the piston push rod device includes a piston body, a lead screw, a sleeve assembly, and a worm gear. One end of the lead screw is fixedly connected to the piston body, and the other end of the lead screw extends into the sleeve assembly and is threadedly connected to the inner wall of the sleeve assembly. The worm gear is fixedly connected to the outer wall of the sleeve assembly. The power storage device outputs rotational torque to the piston push rod device, and the power storage release device includes a worm, with the worm gear meshing with the worm.

[0009] Preferably, the energy storage device includes a first torsion spring, one end of which is fixedly connected to the sleeve assembly, the other end of which is fixedly connected to the housing, and the first torsion spring is in a compressed state.

[0010] Preferably, the sleeve assembly includes a lead screw sleeve, a worm gear sleeve, and a locking assembly. The lead screw sleeve extends into the worm gear sleeve, and the outer wall of the lead screw sleeve and the inner wall of the worm gear sleeve slide in axial engagement along the sleeve assembly. The locking assembly fixes the lead screw sleeve and the worm gear sleeve together. The lead screw extends into the lead screw sleeve (341), and the worm gear is disposed on the outer wall of the worm gear sleeve.

[0011] Preferably, the locking assembly includes a locking ball and a locking groove. The locking groove is fixedly connected to the worm gear sleeve. The lead screw sleeve passes through the locking groove and extends into the worm gear sleeve. The locking ball is disposed on the outer surface of the lead screw sleeve. The locking groove has a receiving groove with a gradually decreasing diameter on the side near the locking ball. The locking ball is embedded in the receiving groove.

[0012] Preferably, the energy storage and release device includes a rotary magnetic brake assembly and a coupling assembly, wherein the rotary magnetic brake assembly is coupled to the piston push rod device through the coupling assembly.

[0013] Preferably, the rotary magnetic brake assembly includes a fixed coil and a rotatably mounted permanent magnet. The permanent magnet is radially magnetized. The magnetic field generated by the fixed coil interacts with the radial magnetic field of the permanent magnet to drive the permanent magnet to rotate or be positioned. An output gear is fixedly mounted on the permanent magnet.

[0014] Preferably, the coupling assembly includes a gear set, the output gear meshes with the transmission start-end gear of the gear set, and the transmission end gear of the gear set is coaxially and fixedly connected to the worm gear.

[0015] According to the present invention, a method for operating a piston motion system for a continuous micro-dose delivery device includes the following steps:

[0016] Step S1: Add sufficient liquid medicine to the medicine storage device;

[0017] Step S2: The control device receives an externally input injection command or injection program;

[0018] Step S3: The control device starts the control of the power storage and release device to release the specified piston stroke. The power storage device outputs rotational torque to push the piston body of the piston push rod device to move in the specified direction for the specified piston stroke.

[0019] Preferably, step S3 includes the following sub-steps:

[0020] Step S3.1: The control device converts the externally input injection command or injection program into a series of corresponding electrical pulse signals and transmits them to the fixed coil;

[0021] Step S3.2: The fixed coil drives the permanent magnet to make corresponding movements to make the output gear rotate, and drives the worm gear to rotate through the gear set. The lead screw sleeve moves into the worm gear sleeve until the locking steel ball is embedded in the receiving groove of the locking slot, so that the lead screw sleeve and the worm gear sleeve are locked together.

[0022] Step S3.3: The control device acquires the locking signals of both the lead screw sleeve and the worm gear sleeve, and releases the piston stroke contained in the externally input injection command through the fixed coil, output gear and gear set to complete the quantitative injection.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. This invention uses a power storage device as a power source to drive a piston by outputting rotational torque. The required number of pulses is calculated based on the dosage to be infused or the distance the piston moves. The power storage device is then precisely controlled by a control device to release the specified piston stroke, which helps to improve the accuracy of the drug delivery dosage. It also has a simple structure and low cost.

[0025] 2. The present invention releases the stroke of the piston pusher device by means of the cooperation of the worm and the worm wheel through the power storage device. The power storage device pushes the piston pusher device to move a certain length into the drug storage device by means of rotational torque, thereby realizing the quantitative injection of drug liquid.

[0026] 3. In this invention, the drug is injected into the drug storage device. At this time, the piston body will move backward as the drug is injected. The lead screw and lead screw sleeve connected to the piston body need to slide freely backward in the worm gear sleeve. When the injection begins, the worm gear sleeve and lead screw sleeve must be locked and cannot slide freely so that the lead screw can push the piston body forward to push the drug, thus realizing the injection of drugs into the drug storage device and quantitative injection. Attached Figure Description

[0027] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0028] Figure 1This is a schematic diagram illustrating the overall structure of the drug delivery device of the present invention;

[0029] Figure 2 This is an exploded view illustrating the overall structure of the rotary magnetic brake assembly, which is the main feature of this invention.

[0030] Figure 3 This is a cross-sectional view that mainly illustrates the overall structure of the rotary magnetic brake assembly of the present invention;

[0031] Figure 4 This is an exploded view of the overall structure of the piston motion system, which is the main feature of this invention.

[0032] Figure 5 This is an exploded view illustrating the overall structure of the locking component, which is the main feature of this invention.

[0033] Figure 6 This is a cross-sectional view that mainly illustrates the overall structure of the piston push rod device of this invention.

[0034] As shown in the figure:

[0035] Energy storage and release device 1 Worm gear 33

[0036] Rotary magnetic brake assembly 11 Sleeve assembly 34

[0037] Fixed coil 111, lead screw sleeve 341

[0038] Permanent magnet 112, worm gear sleeve 342

[0039] Output gear 113 Locking assembly 35

[0040] Magnetic sheet 114, locking steel ball 351

[0041] Limiting hole 115, locking slot 352

[0042] Coupling component 12 Receiving slot 353

[0043] Gear set 121 Locking trigger spring 354

[0044] Transmission starting end gear 122 guide rod 36

[0045] Transmission end gear 123, medicine storage device 4

[0046] Worm 126, Drug storage cavity 41

[0047] Energy storage device 2 Control device 6

[0048] First torsion spring 22 Circuit board 61

[0049] Piston push rod assembly 3 Housing 8

[0050] Piston body 31 Sleeve locking signal switch 81

[0051] Lead screw 32, guide seat 82 Detailed Implementation

[0052] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0053] like Figure 1 As shown, a piston movement system for a continuous micro-dose delivery device according to the present invention includes a piston push rod device 3, a power storage device 2, a power storage release device 1, and a control device 6. Under the action of the control device 6, the power storage release device 1 releases a specified piston stroke, and the power storage device 2 outputs a rotational torque to push the piston body 31 of the piston push rod device 3 to move along a specified direction for a specified piston stroke.

[0054] The specified direction in this application is the direction of movement of the piston body 31 in the piston push rod device 3. The specified piston stroke in this application is the injection command issued by the operator to the control device 6 through information transmission methods such as Bluetooth communication. After receiving the injection command, the control device 6 sends a corresponding electrical pulse to the power storage and release device 1 to release the specified piston stroke.

[0055] Specifically, the injection device also includes a housing 8, which serves as the mounting base for the components on the injection device and has a certain structural strength. The energy storage and release device 1 includes a rotary magnetic brake assembly 11 and a coupling assembly 12. The rotary magnetic brake assembly 11 is electrically connected to the control device 6. The rotary magnetic brake assembly 11 controls the piston stroke of the piston push rod device 3 through the coupling assembly 12, and the energy storage device 2 outputs rotational torque to the piston push rod device 3.

[0056] More specifically, the rotary magnetic brake assembly 11 includes a fixed coil 111 and a rotatably mounted permanent magnet 112. The permanent magnet 112 is radially magnetized. The magnetic field generated by the fixed coil 111 interacts with the radial magnetic field of the permanent magnet 112, causing the permanent magnet 112 to rotate or be positioned. An output gear 113 is fixedly mounted on the permanent magnet 112. The fixed coil 111 includes a coil and a fixed bracket. The coil is wound on the fixed bracket, which is fixedly mounted on the housing 8 by fasteners. A magnetic conductive sheet 114 is also fixedly mounted on the housing 8 by fasteners. The magnetic conductive sheet 114 is provided with a limiting hole 115 that allows the permanent magnet 112 to rotate and be positioned. The permanent magnet 112 is cylindrical in shape. The cylindrical permanent magnet 112 is placed in the limiting hole 115 and is rotatably mounted on the housing 8 through a coaxially mounted rotating shaft. The magnetic sheet 114 can be used to generate an alternating magnetic field. The magnetic field generated by the fixed coil 111 can interact with the magnetic field of the permanent magnet 112, causing the permanent magnet 112 to rotate at a certain angle, especially 180 degrees. The output gear 113 is coaxially and firmly mounted on the permanent magnet 112. The rotation of the permanent magnet 112 can drive the output gear 113 to rotate.

[0057] It should be noted that the rotary magnetic brake assembly 11 of this application can also be a magnetic brake, electromagnetic swing fork or electromagnetic ring, etc., which are capable of outputting torque in the prior art.

[0058] The control device 6 includes a circuit board 61, which integrates a communication module, a data processing module, a data storage module, and a signal conversion module. The signal conversion module and the communication module are electrically connected, and the circuit board 61 is electrically connected to the fixed coil 111. The communication module of the control device 6 can receive wired or wireless infusion command signals or infusion programs from the outside. According to the received infusion information, the data processing module can automatically control the signal conversion module to generate corresponding electrical pulse signals as needed. The electrical pulse signals are transmitted to the fixed coil 111 to control the permanent magnet 112 to rotate a certain angle, thereby controlling the output gear 113 to rotate a certain angle.

[0059] The coupling assembly 12 includes a gear set 121, which comprises multiple meshing gear structures. Each gear in the gear set 121 is rotatably connected to the housing 8 via a rotating shaft. The gear set 121 includes at least one transmission starting gear 122 and at least one transmission ending gear 123. The output gear 113 meshes with the transmission starting gear 122 of the gear set 121. A worm gear 126 is provided on the transmission ending gear 123 of the gear set 121. At least one intermediate transmission gear is provided between the transmission starting gear 122 and the transmission ending gear 123. The intermediate transmission gear meshes with the transmission starting gear 122 and another intermediate transmission gear, or with the transmission ending gear 123 and another intermediate transmission gear, or with two other intermediate transmission gears.

[0060] The power storage device 2 outputs rotational torque. The power storage device 2 includes a first torsion spring 22, which is in a compressed state. The piston push rod device 3 includes a piston body 31, a lead screw 32, a sleeve assembly 34, and a worm gear 33. The piston body 31 is disposed within the drug storage device 4. One end of the lead screw 32 is fixedly connected to the piston body 31, and the other end of the lead screw 32 extends into the sleeve assembly 34 and is threadedly connected to the inner wall of the sleeve assembly 34. The worm gear 33 is fixedly connected to the outer wall of the sleeve assembly 34 and meshes with the worm 126. One end of the first torsion spring 22 is fixedly connected to the sleeve assembly 34, and the other end of the first torsion spring 22 is fixedly connected to the housing 8 of the injection device.

[0061] Furthermore, the sleeve assembly 34 includes a lead screw sleeve 341, a worm gear sleeve 342, and a locking assembly 35. The lead screw sleeve 341 extends into the worm gear sleeve 342, and the outer wall of the lead screw sleeve 341 and the inner wall of the worm gear sleeve 342 are slidably engaged along the axial direction of the sleeve assembly 34. The locking assembly 35 fixes the lead screw sleeve 341 and the worm gear sleeve 342 together. Before the locking assembly 35 fixes the lead screw sleeve 341 and the worm gear sleeve 342 together, the lead screw sleeve 341 can slide along the axis of the sleeve assembly 34 within the worm gear sleeve 342. After the locking assembly 35 fixes the lead screw sleeve 341 and the worm gear sleeve 342 together, there is no relative movement between them.

[0062] The locking assembly 35 includes a locking ball 351 and a locking groove 352. The locking groove 352 is fixedly connected to the worm gear sleeve 342. The lead screw sleeve 341 passes through the locking groove 352 and extends into the worm gear sleeve 342. The locking ball 351 is disposed on the outer surface of the lead screw sleeve 341. The locking groove 352 has a receiving groove 353 with a gradually decreasing diameter on the side near the locking ball 351. The locking ball 351 is embedded and fitted into the receiving groove 353. The receiving groove 353 is formed by the inner wall of the locking groove 352 and the outer wall of the lead screw sleeve 341, and the cross-sectional shape of the receiving groove 353 is approximately "V". When the locking ball 351 enters the locking groove 352 and reaches a certain distance where the gap is less than the diameter of the locking ball 351, the locking ball 351, the locking groove 352, and the lead screw sleeve 341 are mutually locked, and the lead screw sleeve 341 and the worm gear sleeve 342 are mutually locked.

[0063] Furthermore, a locking trigger spring 354 is coaxially sleeved on the lead screw sleeve 341. The locking trigger spring 354 is located on the side of the locking steel ball 351 facing away from the locking slot 352, and the locking trigger spring 354 has a semi-circular groove that engages with the locking steel ball 351. One or more locking steel balls 351 are evenly spaced around the central axis of the lead screw sleeve 341, and the semi-circular grooves on the locking trigger spring 354 correspond to the locking steel balls 351. A sleeve locking signal switch 81 is provided on the housing 8.

[0064] Before use, there is no medicine in the drug storage device 4. The user needs to inject the medicine into the drug storage cavity 41 using a syringe. At this time, the piston body 31 will move backward as the medicine is injected. The lead screw 32 and lead screw sleeve 341 connected to the piston body 31 need to slide freely backward in the worm gear sleeve 342. When the injection begins, the worm gear sleeve 342 and lead screw sleeve 341 must be locked and cannot slide freely in order for the lead screw 32 to push the piston body 31 forward to inject the medicine.

[0065] When injection begins, the turbine starts rotating, and the locking trigger spring 354 rotates along with the turbine. When the sleeve locking signal switch 81 can no longer block the locking trigger spring 354, the locking trigger spring 354 pushes the locking steel ball 351 into the locking slot 352. The gap between the inside of the locking slot 352 and the lead screw sleeve 341 is V-shaped, and the gap decreases as it goes deeper into the locking slot 352. When the locking steel ball 351 reaches a certain distance inside the locking slot 352 where the gap is smaller than the diameter of the locking steel ball 351, the locking steel ball 351, the locking slot 352, and the lead screw sleeve 341 are mutually locked, and the lead screw sleeve 341 and the worm gear sleeve 342 are mutually locked. This solves the problem that the worm gear sleeve 342 and the lead screw sleeve 341 need to slide freely during filling but are locked together during injection.

[0066] Furthermore, a guide rod 36 is fixedly installed on the piston body 31. The length direction of the guide rod 36 is parallel to the length direction of the lead screw 32. A guide seat 82 is provided on the housing 8. The guide rod 36 passes horizontally through the guide seat 82 and slides with it.

[0067] An injection method for a continuous micro-dose delivery device provided by the present invention includes the following steps:

[0068] Step S1: Add sufficient medicine solution to the medicine storage device 4.

[0069] Step S2: Control device 6 receives externally input injection instructions or injection procedures.

[0070] Step S3: The control device 6 starts the control accumulator release device 1 to release the specified piston stroke, and the accumulator device 2 pushes the piston push rod device 3 to move into the drug storage device 4 to move the specified piston stroke, thus completing the quantitative injection.

[0071] Step S3 includes the following sub-steps:

[0072] Step S3.1: The control device 6 converts the externally input injection command or injection program into a series of corresponding electrical pulse signals and transmits them to the fixed coil.

[0073] Step S3.2: The fixed coil 111 drives the permanent magnet 112 to make corresponding movements, causing the output gear 113 to rotate, and through the gear set 121, it drives the worm gear 33 to rotate. The lead screw sleeve 341 moves into the worm gear sleeve 342 until the locking steel ball 351 is embedded in the receiving groove 353 of the locking slot 352, thus locking the lead screw sleeve 341 and the worm gear sleeve 342.

[0074] In step S3.3, the control device 6 obtains the locking signals of both the lead screw sleeve 341 and the worm gear sleeve 342, and releases the piston stroke contained in the externally input injection command through the coil, output gear 113 and gear set 121 to complete the quantitative injection.

[0075] During initial installation, the energy release device 1, energy storage device 2, and piston pusher device 3 are installed in place. Because the three are coupled and static, the piston is positioned at the top of the drug storage cavity 41. The user injects insulin into the drug storage cavity 41 through the injection port using a syringe. The piston body 31 is pushed back by the force, triggering the power switch to connect the circuit. After the injection is completed, the user issues an infusion command via Bluetooth communication through the controller. After receiving the command, the control device 6 sends out a corresponding electrical pulse. The rotating magnetic brake assembly 11 is deflected at an angle under the electrical pulse, and the output gear 113 also rotates at the corresponding angle. The corresponding angle is transmitted through the coupling mechanism, and the locking assembly 35 locks the screw sleeve 341 and the turbine sleeve 342, allowing the energy storage device 2 to push the piston body 31 to make corresponding movements. The squeezed liquid flows out through the tubing and out of the needle tip of the soft needle 56.

[0076] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0077] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not 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 application.

[0078] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A piston motion system for a continuous micro-dose delivery device, characterized in that, It includes a piston push rod device (3), a power storage device (2), a power storage release device (1), and a control device (6). Under the action of the control device (6), the power release device (1) releases the specified piston stroke, and the power storage device (2) outputs rotational torque to push the piston body (31) of the piston push rod device (3) to move the specified piston stroke in the specified direction. The piston push rod device (3) includes a piston body (31), a lead screw (32), a sleeve assembly (34), and a worm gear (33). One end of the lead screw (32) is fixedly connected to the piston body (31), and the other end of the lead screw (32) extends into the sleeve assembly (34) and is threadedly connected to the inner wall of the sleeve assembly (34). The worm gear (33) is fixedly connected to the outer wall of the sleeve assembly (34). The power storage device (2) outputs rotational torque to the piston push rod device (3), and the power storage release device (1) includes a worm (126), and the worm wheel (33) meshes with the worm (126).

2. The piston movement system for a continuous micro-dose delivery device as described in claim 1, characterized in that, The energy storage device (2) includes a first torsion spring (22), one end of which is fixedly connected to the sleeve assembly (34), the other end of which is fixedly connected to the housing (8), and the first torsion spring (22) is in a compressed state.

3. The piston movement system for a continuous micro-dose delivery device as described in claim 1, characterized in that, The sleeve assembly (34) includes a lead screw sleeve (341), a worm gear sleeve (342), and a locking assembly (35). The lead screw sleeve (341) extends into the worm gear sleeve (342), and the outer wall of the lead screw sleeve (341) and the inner wall of the worm gear sleeve (342) slide in a sliding fit along the axial direction of the sleeve assembly (34). The locking assembly (35) fixes the lead screw sleeve (341) and the worm gear sleeve (342) in place. The lead screw (32) extends into the lead screw sleeve (341), and the worm gear (33) is disposed on the outer wall of the worm gear sleeve (342).

4. The piston movement system for a continuous micro-dose delivery device as described in claim 3, characterized in that, The locking assembly (35) includes a locking ball (351) and a locking slot (352). The locking slot (352) is fixedly connected to the worm gear sleeve (342). The lead screw sleeve (341) passes through the locking slot (352) and extends into the worm gear sleeve (342). The locking ball (351) is disposed on the outer surface of the lead screw sleeve (341), and the locking groove (352) is provided with a receiving groove (353) with a gradually decreasing diameter on the side near the locking ball (351), and the locking ball (351) is embedded in the receiving groove (353).

5. The piston movement system for a continuous micro-dose delivery device as described in claim 1, characterized in that, The energy storage and release device (1) includes a rotary magnetic brake assembly (11) and a coupling assembly (12). The rotary magnetic brake assembly (11) is coupled to the piston push rod device (3) through the coupling assembly (12).

6. The piston movement system for a continuous micro-dose delivery device as described in claim 5, characterized in that, The rotary magnetic brake assembly (11) includes a fixed coil (111) and a rotatably mounted permanent magnet (112). The permanent magnet (112) is radially magnetized. The magnetic field generated by the fixed coil (111) interacts with the radial magnetic field of the permanent magnet (112) to drive the permanent magnet (112) to rotate or be positioned. An output gear (113) is fixedly mounted on the permanent magnet (112).

7. The piston movement system for a continuous micro-dose delivery device as described in claim 6, characterized in that, The coupling assembly (12) includes a gear set (121), the output gear (113) meshes with the transmission start end gear (122) of the gear set (121), and the transmission end gear (123) of the gear set (121) is coaxially and fixedly connected to the worm (126).

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