A linear-rotation cross-scale precision puncture instrument with an ultra-long service life

Abstract

The present invention proposes a linear-rotating cross-scale precision puncture instrument with an ultra-long service life, which belongs to the field of cell puncture technology. The puncture instrument includes a bottom unit and a driving unit. The bottom unit includes a fixed bracket, a sliding rod and a puncture needle. The directions of the sliding rod and the puncture needle are the same as the first direction; the driving unit includes a pre-pressing plate, a connecting block, a first piezoelectric body, a second piezoelectric body, a first linking magnet, a second linking magnet, a magnetic friction foot and a pre-tightening magnet. The magnetic friction foot is in adsorption contact with the sliding rod. By applying a sawtooth wave electrical signal to both ends of the two piezoelectric bodies, the piezoelectric body is stretched and deformed, thereby driving the magnetic friction foot to move, and the sliding rod is driven by friction to move, thereby driving the puncture needle to move linearly or rotate. The unique advantage of the present invention is that when the magnetic friction foot is worn, it will always adapt to maintain a relatively constant and stable friction force with the sliding rod, and the rotational and linear degrees of freedom share a magnetic friction foot and a pre-tightening magnet.

Description

Technical Field

[0001] The present invention belongs to the technical field of cell puncture, and in particular relates to a linear-rotational cross-scale precision puncture instrument with an ultra-long service cycle. Background Art

[0002] A cell puncture instrument is a device used to accurately puncture a single cell for biological experiments. It is widely used in the fields of cell biology, gene editing, molecular biology, in vitro fertilization, etc. Its main function is to penetrate the cell membrane through a micro needle or probe to perform operations such as cell nucleus injection, genetic material introduction, and drug delivery. Early cell puncture mainly relied on manual operation under a microscope, and researchers manually controlled the micro needle to puncture the cell. This method relies on the operator's experience and skills. Although it can complete basic puncture tasks, it has low accuracy and is easy to damage cells. Because cells are small and fragile, manual puncture can easily cause cell membrane rupture, affecting the consistency of experimental results. Therefore, the application scenarios of this manual puncture method are relatively limited, and it is suitable for experiments with a small number of samples and low technical requirements.

[0003] With the advancement of technology, mechanically driven puncture devices have gradually replaced manual operations. This type of puncture instrument is usually equipped with a micro-control system, which controls the movement of the microneedle through a precision motor or stepper motor to achieve a more stable puncture operation. Modern mechanical puncture instruments can use a fine-tuning mechanism to control the displacement of the needle, so that it can pierce the target cells more accurately while reducing damage to the cells. Mechanically driven puncture instruments have greatly improved the success rate of puncture and the repeatability of experiments, and are suitable for experimental operations of batch samples. Piezoelectric driven puncture technology is a breakthrough in recent years. Compared with traditional mechanical drives, piezoelectric elements have the advantages of fast response speed and high displacement accuracy. This technology controls the displacement of the puncture needle through the deformation of the piezoelectric material, and the movement range of the needle tip can be accurate to the nanometer level, thereby significantly improving the accuracy of puncture. This technology is particularly suitable for operations that require extremely high precision, such as introducing molecular substances such as DNA, RNA, and proteins into single cells. The application of piezoelectric driven puncture technology not only improves the success rate of cell puncture, but also effectively reduces the cell damage rate.

[0004] Since direct-drive piezoelectric actuators have an extremely long service life, current piezoelectric-driven puncture instruments are usually piezoelectric direct-drive drives. However, direct-drive piezoelectric actuators can usually only achieve micron-level displacements, which means that additional manual operating devices or electromagnetic drive devices are required for long-stroke driving, increasing the complexity of the system. Other types of piezoelectric actuators, such as piezoelectric inertial drive, ultrasonic drive, and inchworm drive, rely on the friction of the contact surface to achieve movement. This friction will cause gradual wear of key components, affecting the accuracy and life of the equipment. In the field of cell puncture, puncture instruments are required to have an extremely long service life and stability. Therefore, the above-mentioned types of piezoelectric actuators still have no commercial products. Friction and wear problems are a major limitation for applications that require extremely high precision. How to design a cross-scale precision puncture instrument with an ultra-long service life is still a key issue that needs to be solved. Summary of the invention

[0005] In order to solve the problems in the prior art, the present invention proposes a linear-rotating cross-scale precision puncture instrument with an ultra-long service life.

[0006] The technical solution adopted by the present invention is as follows:

[0007] On the one hand, the present invention proposes a linear rotary cross-scale precision puncture instrument with an ultra-long service life, comprising a bottom unit and a driving unit, wherein the bottom unit comprises a fixed bracket, a slide rod is slidably mounted on the fixed bracket through a linear bearing, a puncture needle is fixed to the top of the slide rod through a connecting column, and the directions of the slide rod and the puncture needle are the same as the first direction;

[0008] The driving unit includes a pre-stressing plate, a connecting block, a first piezoelectric body, a second piezoelectric body and a magnetic friction foot. The connecting block is L-shaped, and one end of the first piezoelectric body and one end of the second piezoelectric body are respectively embedded and fixed on the inner sides of the two ends. The other ends of the two piezoelectric bodies are respectively fixed with linking magnets. The magnetic friction foot is adsorbed between the two linking magnets, and the piezoelectric bodies are both expanded and contracted with the voltage changes at the two ends; the pre-stressing plate is fixed with a pre-tightening magnet, and the pre-tightening magnet repels the magnetic poles of the magnetic friction foot, so as to press the magnetic friction foot against the two linking magnets through repulsion; the pre-stressing plate and the connecting block are fixed on a fixed bracket, and the magnetic friction foot is in adsorption contact with the sliding rod; by applying sawtooth wave electrical signals to the two ends of the two piezoelectric bodies respectively, the piezoelectric bodies are expanded and contracted, thereby driving the magnetic friction foot to move, and the sliding rod is driven to move through friction, thereby driving the puncture needle to move linearly or rotate along the first direction.

[0009] On the other hand, the present invention also proposes a control method based on the above-mentioned linear rotation cross-scale precision puncture instrument, comprising:

[0010] If the puncture needle needs to move linearly along the first direction, a sawtooth wave is applied to both ends of the second piezoelectric body. When the duty ratio of the applied sawtooth wave is between 90% and 100%, the puncture needle moves forward along the first direction; when the duty ratio of the applied sawtooth wave is between 0% and 10%, the puncture needle moves in the reverse direction along the first direction;

[0011] If the puncture needle needs to rotate, a sawtooth wave is applied to both ends of the first piezoelectric body. When the duty cycle of the applied sawtooth wave is between 90% and 100%, the puncture needle rotates forward. When the duty cycle of the applied sawtooth wave is between 0% and 10%, the puncture needle rotates reversely.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present invention proposes a linear rotary cross-scale precision puncture instrument with an ultra-long service life. The driver proposed in the present invention can arbitrarily replace the magnetic friction foot and the pre-tightening magnet to adapt to different performance requirements. The drive unit adopts a modular design, which makes the driver have the advantages of simple structure, strong wear resistance, wear self-adaptation, modular replacement, and no need for pre-tightening and loosening prevention, and has the potential to achieve durable drive.

[0014] When the magnetic friction foot of the linear-rotation cross-scale precision puncture instrument is worn, it will always adapt to maintain a relatively constant and stable friction force with the sliding rod of the ferromagnetic material. At the same time, the rotational and linear degrees of freedom share a magnetic friction foot and a pre-tightening magnet, which simplifies the structure of the puncture instrument.

[0015] The present invention has great application prospects in precision scientific instruments and medical devices such as cell puncture and micro-nano manipulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an overall schematic diagram of the linear rotation cross-scale precision puncture instrument with an ultra-long service life proposed by the present invention;

[0017] Figure 2 This is an exploded diagram of the structure of the linear-rotating cross-scale precision puncture instrument with an ultra-long service life proposed by the present invention;

[0018] Figure 3 It is a schematic diagram of the structure of the upper cover of the puncture instrument of the present invention;

[0019] Figure 4 It is a schematic structural diagram of the bottom unit in the puncture instrument of the present invention;

[0020] Figure 5 It is a schematic structural diagram of the lower cover of the puncture instrument of the present invention;

[0021] Figure 6 It is a schematic diagram of the structure of the fixed support in the puncture instrument of the present invention;

[0022] Figure 7 It is a schematic diagram of the structure of the driving unit in the puncture instrument of the present invention;

[0023] Figure 8 It is a structural schematic diagram of a connecting block in the puncture instrument of the present invention;

[0024] Fig. 9 It is a schematic diagram of the structure of the pre-compression plate in the puncture instrument of the present invention;

[0025] Fig.10 It is a schematic diagram of the structure of the magnetic friction foot in the puncture instrument of the present invention;

[0026] Fig.11 It is a working principle diagram of the puncture instrument of the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described and illustrated below in conjunction with specific embodiments. The embodiments are merely exemplary of the present disclosure and do not define the scope of limitation. The technical features of each embodiment of the present invention may be combined accordingly without conflicting with each other.

[0028] , after long-term frequent reciprocating drive between the friction foot and the mover of the same type of driver, the friction foot is worn, and the friction force gradually decreases until it disappears, resulting in drive failure. The piezoelectric inertial drive principle adopted by the linear rotary cross-scale precision puncture instrument with an ultra-long service life proposed by the present invention realizes long-stroke drive through stick-slip friction. When the magnetic friction foot is worn, the sliding rod of the ferromagnetic material will always adapt to maintain a relatively constant and stable friction force. In this embodiment, the specific technical solution is as follows.

[0029] The overall schematic diagram of a linear rotation cross-scale precision puncture instrument with an ultra-long service life designed by the present invention is as follows Figure 1 As shown, its structural explosion diagram is as follows Figure 2 As shown, it mainly includes an upper cover 1, a bottom unit 2 and a driving unit 3; the upper cover 1 and the driving unit 3 are assembled on the bottom unit 2.

[0030] The structure of the upper cover 1 is as follows Figure 3 As shown, it includes an upper cover assembly surface 1-1, an upper slide bar nesting groove 1-2, an upper inlay groove 1-3, an upper slide bar guide groove 1-4, a hexagonal nut nesting groove 1-5, an upper cover cavity 1-6, an upper slide bar nesting column 1-7, an upper cover assembly countersunk hole 1-8 and an upper slide bar guide column 1-9; the bottom unit 2 structure is as shown Figure 4As shown, it consists of a puncture needle 2-1, a catheter 2-2, a connecting column 2-3, a slide rod 2-4, a lower cover 2-5, a fixed bracket 2-6 and a linear bearing 2-7; the catheter 2-2 is connected to the inside of the puncture needle to provide the puncture needle with liquid to be injected; the connecting column 2-3 connects the puncture needle 2-1 with the slide rod 2-4, wherein the catheter 2-2 is also led out from the middle of the connecting column 2-3, and two linear bearings 2-7 are respectively embedded between the fixed brackets 2-6; the fixed bracket 2-6 is embedded in the lower cover 2-5.

[0031] The structure of the drive unit 3 is as follows Figure 7 As shown, the driving unit 3 is composed of a first piezoelectric body 3-1, a connecting block 3-2, a preload plate 3-3, a second piezoelectric body 3-4, a second linking magnet 3-5, a magnetic friction foot 3-6, a preload magnet 3-7 and a first linking magnet 3-8; the magnetic friction foot 3-6 is as shown Fig.10 As shown, it and the second link magnet 3-5 and the first link magnet 3-8 are all single-pole magnetized, one end of the first piezoelectric body 3-1 and the second piezoelectric body 3-4 are respectively embedded in the connecting block 3-2, and the other end is respectively connected to the first link magnet 3-8 and the second link magnet 3-5, the piezoelectric body and the link magnet are fixed by gluing, and the piezoelectric body can be stretched and contracted with the voltage at both ends. The stretching direction of the first piezoelectric body 3-1 is the second direction, and the stretching direction of the second piezoelectric body 3-4 is the first direction. The second direction is perpendicular to the first direction, and the first direction is perpendicular to the sliding rod 2-4. The slide bar 2-4 is made of ferromagnetic material, and the magnetic friction foot 3-6 fits with the slide bar 2-4 under the action of magnetic attraction, wherein the first link magnet 3-8 and the second link magnet 3-5 limit the magnetic friction foot 3-6 and provide adsorption force; the pre-tightening magnet 3-7 is embedded in the pre-stressing plate 3-3, and the pre-tightening magnet 3-7 is located at the oblique side of the magnetic friction foot 3-6 to repel the magnetic friction foot 3-6, and the magnetic friction foot 3-6 is pressed to the first link magnet 3-8 and the second link magnet 3-5 through the repulsive force, thereby improving the overall magnetic stiffness to improve the response frequency of the driver.

[0032] The structure of the lower cover 2-5 is as follows Figure 5 As shown, it includes a lower cover cavity 2-5-1, a lower slide rod guide groove 2-5-2, a lower slide rod guide column 2-5-3, a lower cover assembly surface 2-5-4, a lower cover assembly through hole 2-5-5 and an upper slide rod nesting groove 2-5-6 and a lower slide rod nesting column 2-5-7; the fixed bracket 2-6 structure is as shown Figure 2-6 As shown, it includes a fixed bracket countersunk hole 2-6-1, a drive unit assembly plate 2-6-2, a cover fixing threaded hole 2-6-3, a pre-pressing plate assembly threaded hole 2-6-4, a slide rod cavity 2-6-5, a limit link body 2-6-6 and a bearing nesting column 2-6-7; the structure of the connecting block 3-2 is as shown Figure 8As shown, it includes a connecting block side plate 3-2-1, a connecting block fixing plate 3-2-2, a second mounting groove 3-2-3, a connecting block fixing threaded hole 3-2-4 and a first mounting groove 3-2-5; the pre-pressing plate 3-3 is structured as shown Fig. 9 As shown, it includes a U-shaped inlay groove 3-3-1, a pre-pressing plate main board 3-3-2 and a pre-pressing plate countersunk hole 3-3-3.

[0033] The assembly process of the present invention is specifically as follows:

[0034] The linear bearing 2-7 is embedded in the bearing assembly hole 2-6-8, and the limiting link 2-6-6 limits the linear bearing 2-7. Then the slide bar 2-4 cooperates with the linear bearing 2-7 to realize linear motion in the first direction. The slide bar cavity 2-6-5 and the slide bar 2-4 have a clearance fit to avoid interference when the slide bar 2-4 moves; a first embedding groove 3-2-5 is provided on the connecting block side plate 3-2-1, and a second embedding groove 3-2-3 and a connecting block fixing threaded hole 3-2-4 are provided on the connecting block fixing plate 3-2-2. The first embedding groove 3-2-5 and the second embedding groove 3-2-3 are used to limit the first piezoelectric body 3-1 and the second piezoelectric body 3-4 respectively; when one end of the first piezoelectric body 3-1 and the second piezoelectric body 3-4 are glued to the first embedding groove 3-2-5 and the second inlay groove 3-2-3, and the other end is glued and connected with the first link magnet 3-8 and the second link magnet 3-5 respectively, and the magnetic friction foot 3-6 is adsorbed on the first link magnet 3-8 and the second link magnet 3-5, and the drive unit 3 is assembled; then, the drive unit 3 is fixed on the fixed bracket 2-6 by passing the screw through the countersunk hole 2-6-1 of the fixed bracket and screwing into the fixing threaded hole 3-2-4 of the connecting block; the pre-tightening magnet 3-7 is embedded in the U-shaped inlay groove 3-3-1 and fixed by gluing, a pre-stressing plate countersunk hole 3-3-3 is opened on the pre-stressing plate main board 3-3-2, and the pre-stressing plate 3-3 is fixed on the fixed bracket 2-6 by passing the screw through the countersunk hole 3-3-3 of the pre-stressing plate and screwing into the pre-stressing plate assembly threaded hole 2-6-4.

[0035] The fixed bracket 2-6 is embedded into the lower cover cavity 2-5-1, and the lower cover assembly surface 2-5-4 limits the fixed bracket 2-6. The lower slide bar nesting column 2-5-7 and the lower slide bar lead-out column 2-5-3 respectively open the lower slide bar nesting groove 2-5-6 and the lower slide bar lead-out groove 2-5-2 to reserve movement avoidance space for the slide bar 2-4. The hexagon socket nut is nested in the hexagon socket nut nesting groove 1-5 and fixed by adhesive connection. The upper slide bar nesting column 1-7 and the upper slide bar lead-out column An upper slide bar nesting groove 1-2 and an upper slide bar lead-out groove 1-4 are also provided in 1-9 to reserve movement avoidance space for the slide bar 2-4; the upper cover 1 is assembled onto the bottom unit 2, and a screw is passed through the lower cover assembly hole 2-5-5 and screwed into the hexagonal nut embedded in the upper cover 1 to complete the assembly of the entire puncture instrument. At this time, the fixed bracket 2-6 is clamped between the upper cover 1 and the lower cover 2-5; the fixed bracket 2-6, the driving unit 3, the upper cover 1 and the lower cover 2-5 are all made of non-ferromagnetic materials.

[0036] In the present invention, the linear rotation cross-scale precision puncture instrument with an ultra-long service life can realize the movement of the puncture needle rotational freedom and linear freedom. Taking the linear freedom as an example, the working principle is as follows: Fig.11 shown.

[0037] The linear freedom of movement is achieved by applying a sawtooth voltage to both ends of the second piezoelectric body 3-4. If the puncture needle 2-1 is to move in the first positive direction, a sawtooth wave with a duty cycle of 90% to 100% (not including 100%) needs to be applied to both ends of the second piezoelectric body 3-4. Each cycle of the sawtooth wave contains two time periods: voltage increase (t0 to t1) and voltage decrease (t1 to t2). For a sawtooth wave with a duty cycle of 90% to 100%, the voltage increases slowly and the voltage decreases quickly. At the initial stage, at time t0, the drive unit is in a stationary stage; during the time period t0 to t1, the drive unit is in a sticking stage, and the second piezoelectric body 3-4 drives the magnetic friction foot 3-6 to slowly extend. At this time, there is static friction between the magnetic friction foot 3-6 and the slide bar 2-4, and the slide bar 2-4 is displaced d in the first direction. f During the time period t1 to t2, the driving unit is in the sliding stage, the second piezoelectric body 3-4 contracts rapidly, and the magnetic friction foot 3-6 contracts rapidly under the attraction of the second link magnet 3-5 and the repulsion of the preload magnet 3-7. At this time, there is a dynamic friction force between the magnetic friction foot 3-6 and the slide bar 2-4, and the slide bar 2-4 moves in the opposite direction along the first direction d b , due to the difference in magnitude between static friction and dynamic friction, the displacement d f Greater than displacement d b ; At this point, a cycle is completed, and the step displacement is d1=d f -d bThe slide bar 2-4 drives the puncture needle 2-1, and the long stroke output is realized by accumulating the step displacement in each cycle. Similarly, if the puncture needle 2-1 is to move in the first reverse direction, a sawtooth wave voltage with a duty cycle of 0% to 10% (excluding 0%) is applied to both ends of the second piezoelectric body 3-4 to realize reverse driving.

[0038] The working principle of the rotational freedom of the puncture needle is similar to that of the above-mentioned linear freedom, which is achieved by applying a sawtooth voltage to both ends of the first piezoelectric body 3-1. The forward rotation and reverse rotation of the rotational freedom require applying a sawtooth wave with a duty cycle of 90%~100% and a duty cycle of 0%~10% to both ends of the first piezoelectric body 3-1, respectively.

[0039] The unique advantage of the designed linear-rotation cross-scale precision puncture instrument with an ultra-long service life is that when the magnetic friction foot 3-6 is worn, it will always adapt to maintain a relatively constant and stable friction force with the ferromagnetic slide bar 2-4. At the same time, the rotational and linear degrees of freedom share a magnetic friction foot 3-6 and a preload magnet 3-7.

[0040] The present invention adopts modular design, which makes the puncture instrument have the advantages of simple structure, cross-scale drive, strong wear resistance, wear self-adaptation, modular replacement, no need for pre-tightening and loosening prevention, and has the potential to achieve an ultra-long service life. The present invention has great application prospects in precision scientific instruments and medical devices such as cell puncture and micro-nano operation.

[0041] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. For ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A linear-rotation cross-scale single-cell precision puncture instrument with an ultra-long service life, characterized in that: It comprises a bottom unit and a driving unit, wherein the bottom unit comprises a fixed bracket, a sliding rod is slidably mounted on the fixed bracket through a linear bearing, a puncture needle is fixed to the top of the sliding rod through a connecting column, and the directions of the sliding rod and the puncture needle are the same as the first direction; The driving unit includes a pre-stressing plate, a connecting block, a first piezoelectric body, a second piezoelectric body and a magnetic friction foot. The connecting block is L-shaped, and one end of the first piezoelectric body and one end of the second piezoelectric body are respectively embedded and fixed on the inner sides of the two ends. The other ends of the two piezoelectric bodies are respectively fixed with connecting magnets. The magnetic friction foot is adsorbed between the two connecting magnets, and the piezoelectric bodies can both expand and contract and deform with the change of the voltage applied to the two ends thereof; the pre-stressing plate is fixed with a pre-tightening magnet, and the pre-tightening magnet repels the magnetic poles of the magnetic friction foot, so as to press the magnetic friction foot against the two connecting magnets through repulsion; the pre-stressing plate and the connecting block are fixed on a fixed bracket, and the magnetic friction foot is in adsorption contact with the sliding rod; by applying a sawtooth wave electrical signal to the two ends of the two piezoelectric bodies respectively, the piezoelectric bodies are expanded and contracted, thereby driving the magnetic friction foot to move, and the sliding rod is driven to move through friction, thereby driving the puncture needle to move linearly or rotate along the first direction.

2. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: The expansion and contraction direction of the second piezoelectric body is the first direction, and the expansion and contraction direction of the first piezoelectric body is perpendicular to the first direction.

3. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: The bottom unit further includes a lower cover, and the puncture instrument further includes an upper cover, and the upper cover and the lower cover are used to cooperate and encapsulate the fixed bracket and the driving unit.

4. The linear rotation cross-scale single-cell precision puncture instrument according to claim 3 is characterized in that: The upper cover and the lower cover are made of non-ferromagnetic material.

5. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: The puncture needle is hollow, and the bottom unit further comprises a catheter for introducing the liquid to be injected into the puncture needle.

6. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: Two linear bearings are provided to enhance the stability of the sliding rod moving along the first direction.

7. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: The slide bar is made of ferromagnetic material; except for the slide bar, two piezoelectric bodies, two linking magnets, magnetic friction feet, and pre-tightening magnets, other components in the fixed bracket and the driving unit are made of non-ferromagnetic materials.

8. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: The linking magnet and the piezoelectric body are fixed by gluing.

9. The linear rotation cross-scale single-cell precision puncture instrument according to claim 1 is characterized in that: The pre-pressing plate is provided with a U-shaped embedding groove, and the pre-tightening magnet is embedded in the U-shaped embedding groove and fixed by gluing.

10. A control method based on the linear rotation cross-scale single-cell precision puncture instrument according to claim 1, characterized in that: The method comprises: If the puncture needle needs to move linearly along the first direction, for the positive movement along the first direction, a sawtooth wave with a duty cycle of 90% to 100% is applied to both ends of the second piezoelectric body. During the voltage increase stage within one cycle of the sawtooth wave, the magnetic friction foot drives the slide bar to move forward in the first direction through static friction; during the voltage reduction stage within one cycle of the sawtooth wave, the magnetic friction foot drives the slide bar to move in the opposite direction through dynamic friction, and the slide bar realizes positive step displacement as a whole within one cycle; accumulating the step displacement of each cycle, the slide bar drives the puncture needle to realize positive movement along the first direction; For the reverse movement along the first direction, a sawtooth wave with a duty cycle of 0% to 10% is applied to both ends of the second piezoelectric body. During the voltage increase stage within one cycle of the sawtooth wave, the magnetic friction foot drives the slide bar to move forward through the dynamic friction force; during the voltage decrease stage within one cycle of the sawtooth wave, the magnetic friction foot drives the slide bar to move in the reverse direction through the static friction force, and the slide bar realizes a reverse step displacement as a whole within one cycle; the step displacement of each cycle is accumulated, and the slide bar drives the puncture needle to realize the reverse movement along the first direction; If the puncture needle needs to rotate, a sawtooth wave is applied to both ends of the first piezoelectric body. When the duty cycle of the applied sawtooth wave is between 90% and 100%, the puncture needle rotates forward. When the duty cycle of the applied sawtooth wave is between 0% and 10%, the puncture needle rotates reversely.

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