Piezoelectric driving method and system based on magnetic suspension

Abstract

The invention belongs to the technical field of piezoelectric driving, and relates to a piezoelectric driving method and system based on magnetic levitation, and the piezoelectric driving method comprises the steps: S1, arranging a first magnet on the outer surface of a stator on a piezoelectric block; a second magnet is arranged on the outer surface of the driven part; the first magnet and the second magnet are oppositely arranged, and the mutually contacted surfaces of the first magnet and the second magnet have the same magnetism; and S2, the piezoelectric block is excited by the outside to generate amplitude, the amplitude generated by the piezoelectric block is transmitted to the driven part through magnetic repulsive force generated between the first magnet and the second magnet, and the driven part is pushed to generate displacement and force in a suspension state. The characteristic that like poles of magnetic materials repel is utilized, driving is achieved without direct contact between a driven component and the stator, and therefore the problem of friction loss is solved, and the service life of piezoelectric driving is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of piezoelectric driving, and relates to a piezoelectric driving method and system based on magnetic suspension. Background Art

[0002] The drive device is a common power equipment in industry. Most traditional drive devices work based on the electromagnetic principle. Specifically, the starter rotor is rotated by the energized coil in the magnetic field, and the small gear on the rotor drives the engine flywheel to rotate. However, due to the defects of low motor conversion efficiency and small displacement of traditional motors, piezoelectric drive has emerged. This is because the piezoelectric drive has no windings and magnetic poles, and does not need to generate motive force through electromagnetic action. It uses piezoelectric ceramics to convert vibration energy into rotational energy to generate power.

[0003] Piezoelectric drive devices are generally composed of a vibrating body (equivalent to the stator in a traditional motor, made of piezoelectric ceramics and metal elastic materials) and a moving body (equivalent to the rotor in a traditional motor, made of elastic body, friction material, plastic, etc.). When a 1Hz-2MHz AC voltage is applied to the piezoelectric ceramic vibrator of the vibrating body, the inverse piezoelectric effect or electrostrictive effect is used to make the stator produce microscopic mechanical vibrations. This vibration is then transformed into rotational or linear motion through resonance amplification and friction coupling.

[0004] Although the existing piezoelectric drive device can meet the actual needs, since the stator and the rotor are in contact, friction loss will be generated during the drive, which affects the service life of the piezoelectric drive device. Therefore, in order to reduce friction loss, the existing technology generally sets a layer of special friction material on the surface where the stator and the rotor contact. Referring to the patent document with the announcement number CN206004554U, a traveling wave ultrasonic motor stator and a motor provided with the traveling wave ultrasonic motor stator are disclosed. The motor includes a bearing, a rotor, a friction layer and a traveling wave ultrasonic motor stator which are sequentially sleeved on the rotating shaft, and an upper cover and a lower cover are arranged at both ends of the rotating shaft; the rotor and the traveling wave ultrasonic motor stator are fitted, and a friction layer is covered on the contact surface of the rotor and the traveling wave ultrasonic motor stator. Specifically, the friction material of the friction layer can be selected from polymer-based friction materials, ceramic coating friction materials, powder metallurgy friction materials, metal-plated friction materials, etc. Because the ultrasonic motor relies on friction coupling to transmit power, setting a friction layer is conducive to extending the service life of the motor.

[0005] However, since piezoelectric drive devices all use the inverse piezoelectric effect of piezoelectric ceramics to produce deformation and use friction to transmit kinetic energy to the driven parts, after long-term operation, the friction material is worn out, causing the friction of the friction material to be lower than the critical value, or because of continuous friction, a gap will be generated between the stator and the driven parts, causing the entire piezoelectric drive device to fail, affecting the service life of the piezoelectric drive device. In addition, the working life of existing piezoelectric ceramics can reach billions to tens of billions of times. With such a long working time, it is difficult to match friction materials with a corresponding working life, and it is difficult to meet actual needs. Summary of the invention

[0006] In order to solve the technical problem that the long-term movement of the existing piezoelectric driving device may cause damage to the friction material and affect the service life of the piezoelectric driving device, the present invention provides a piezoelectric driving method and system based on magnetic suspension.

[0007] The present invention arranges a pair of magnetic materials with the same polarity on the contact surface of the driven component and the stator. When an excitation voltage is applied to the piezoelectric block, an amplitude is generated. In a suspended state, the driving is achieved without direct contact between the driven component and the stator by utilizing the property that the magnetic materials repel each other with like polarities, thereby solving the problem of friction loss and improving the service life of the piezoelectric drive.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A piezoelectric driving method based on magnetic levitation comprises the following steps:

[0010] S1. A first magnet is arranged on the outer surface of the stator on the piezoelectric block; a second magnet is arranged on the outer surface of the driven component; the first magnet and the second magnet are arranged facing each other, and the polarity of the first magnet and the second magnet on the side in contact with each other is the same;

[0011] S2. The piezoelectric block generates an amplitude when stimulated by the outside world. The amplitude generated by the piezoelectric block is transmitted to the driven component through the magnetic repulsion force generated between the first magnet and the second magnet, and the driven component is pushed to generate displacement and force in a suspended state.

[0012] It is further defined that in step S2, the magnetic repulsion satisfies the following relationship:

[0013] F=(3μ0×m1×m2) / 4πd 4

[0014] Where: F is the magnetic repulsion, unit N; μ0 is the vacuum magnetic permeability, unit N / A 2 ; m1 is the magnetic dipole moment of the first magnet, unit A·m 2 ; m2 is the magnetic dipole moment of the second magnet, unit A·m 2; d is the vertical distance between the first magnet and the second magnet, in m.

[0015] It is further defined that in step S2, the linear relationship between the amplitude and the excitation voltage, and the relationship between the amplitude and the spacing satisfy:

[0016] Aw=kV

[0017] Aw=η×d

[0018] Where: Aw is the surface amplitude of the piezoelectric ceramic, k is the electromechanical coupling coefficient; V is the excitation voltage applied to the piezoelectric block; η is the proportional factor of the amplitude and spacing desired in the design; d is the vertical spacing between the first magnet and the second magnet.

[0019] It is further defined that the thickness of the first magnet is 0.05 mm to 10 mm; the thickness of the second magnet is 0.05 mm to 10 mm; and the vertical distance between the first magnet and the second magnet is 0.1 mm to 5 mm.

[0020] It is further defined that the first magnet and the second magnet are made of the same material, both of which are neodymium iron boron, samarium cobalt or barium ferrite.

[0021] It is further defined that the excitation voltage is 1V to 1000V.

[0022] It is further defined that the first magnet and the second magnet are each one or more groups, and in each group, the ratio of the number of first magnets to the second magnets is 2:3, multiple first magnets are arranged at equal intervals on the piezoelectric block, and multiple second magnets are arranged at equal intervals on the driven component.

[0023] It is further defined that the center distance L between two adjacent first magnets is L=λ; the center distance S between two adjacent second magnets is S=λ / 2.

[0024] A piezoelectric drive system for implementing the piezoelectric drive method based on magnetic levitation, the piezoelectric drive system comprising:

[0025] It includes a piezoelectric block, a stator and a driven component, wherein the stator is arranged on the piezoelectric block; a first magnet is arranged on the outer surface of the stator; a second magnet is arranged on the driven component, the first magnet and the second magnet are facing each other and staggered, and the magnetic properties of the first magnet and the second magnet on the side in contact with each other are the same.

[0026] It is further defined that the first magnet and the second magnet are each one or more groups, and in each group, the ratio of the number of first magnets to the second magnets is 2:3, multiple first magnets are arranged at equal intervals on the piezoelectric block, and multiple second magnets are arranged at equal intervals on the driven component.

[0027] Compared with the traditional technology, the beneficial effects of the present invention are:

[0028] 1. In the present invention, a first magnet is arranged on the stator surface of the piezoelectric block, and a second magnet with the same polarity as the first magnet is arranged on the driven component, and the first magnet and the second magnet are arranged opposite to each other. The piezoelectric block generates amplitude when stimulated by the outside world, and drives the stator to vibrate to generate displacement and force. At this time, the characteristic of like repels like is utilized to generate magnetic repulsion between the first magnet and the second magnet, and the displacement and force generated by the piezoelectric block are transmitted through the magnetic repulsion. In a suspended state, the transmitted displacement and force act on the driven component, so that the driven component generates displacement and force, thereby driving the driven component to move. Thereby effectively avoiding the friction loss problem caused by direct contact between the stator and the driven component, so that the life of the piezoelectric drive depends entirely on the attenuation of the depolarization of the material of the piezoelectric block and the magnet material, thereby extending the service life of the drive.

[0029] 2. The present invention constructs the relationship between the thickness of the first magnet, the thickness of the second magnet, the distance between the first magnet and the second magnet, and the magnetic repulsion, thereby ensuring that the magnetic repulsion generated in the state of no direct contact can well drive the driven component to move according to the corresponding amplitude, thereby improving the stability of the drive.

[0030] 3. In the present invention, the thickness of the first magnet, the thickness of the second magnet, and the distance between the first magnet and the second magnet are optimized and limited, so that while ensuring sufficient magnetic repulsion, it is beneficial for the piezoelectric ceramic to achieve effective vibration transmission at a relatively low voltage.

[0031] 4. The present invention constructs the relationship between the magnet spacing and the wavelength so that the amplitude generated by the stator on the piezoelectric block can achieve continuous propulsion of the driven component, avoiding the occurrence of stagnation between the stator and the driving component, which affects the smooth progress of the drive. Preferably, the number ratio of each group of first magnets to each group of second magnets is 2:3, the center spacing between two adjacent first magnets is L = λ; the center spacing between two adjacent second magnets is S = λ / 2, at this time, the stator can generate a stable traveling wave mode amplitude.

[0032] 5. The present invention also provides a piezoelectric drive system, which can transmit the displacement and force generated by the piezoelectric block to achieve driving in a non-contact state by means of the magnetic repulsion generated by magnetic materials of the same polarity. The entire driving process will not generate friction loss, forming a wear-free piezoelectric drive mode, thereby increasing the service life of the piezoelectric drive system; the piezoelectric drive system with this structure has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of an existing piezoelectric drive device;

[0034] Figure 2 A schematic diagram of a piezoelectric drive system provided by the present invention;

[0035] Figure 3 The working principle of the piezoelectric driving method based on magnetic suspension of the present invention;

[0036] Figure 4 It is a schematic diagram of the rotation trajectory of the piezoelectric drive based on magnetic levitation of the present invention;

[0037] in:

[0038] 100 - piezoelectric block; 200 - stator; 300 - driven component; 400 - first magnet; 500 - second magnet. DETAILED DESCRIPTION

[0039] The objectives, technical solutions and beneficial effects of the present invention are now further described in detail in conjunction with the accompanying drawings and embodiments.

[0040] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0041] See also Figure 1 In the existing piezoelectric driving device, the piezoelectric block 100 and the stator 200 placed on the piezoelectric block 100 are at the bottom, and the driven component 300 (preferably a slide bar) is at the top. The movement direction of the stator 200 is an amplitude movement in the up-and-down direction, and the driven component 300 is a horizontal movement. The stator 200 and the driven component 300 are at the contact point ( Figure 1 The stator 200 and the driven component 300 are in contact and the upper driven component 300 is driven by friction. Since this piezoelectric drive device is driven by contact friction, the overall life of the piezoelectric drive device is limited by the friction degree of the contact surface. After a long period of operation, the friction force of the friction material is lower than the critical value or a gap is generated between the stator 200 and the driven component 300 due to friction, and the drive of the entire piezoelectric drive device will fail, affecting the service life.

[0042] In order to solve the defects of the existing piezoelectric driving device, the present invention provides a piezoelectric driving method based on magnetic suspension, comprising the following steps:

[0043] S1. A first magnet 400 is disposed on the outer surface of the stator 200 on the piezoelectric block 100; a second magnet 500 is disposed on the outer surface of the driven component 300; the first magnet 400 and the second magnet 500 are disposed opposite to each other, and the polarity of the first magnet 400 and the second magnet 500 on the side in contact with each other is the same;

[0044] S2. The piezoelectric block 100 generates an amplitude when stimulated by the outside world. The amplitude generated by the piezoelectric block 100 is transmitted to the driven component 300 through the magnetic repulsion force generated between the first magnet 400 and the second magnet 500, pushing the driven component 300 to generate displacement and force in a suspended state.

[0045] In step S2, the magnetic repulsion satisfies the following relationship:

[0046] F=(3μ0×m1×m2) / 4πd 4

[0047] Where: F is the magnetic repulsion, unit N; μ0 is the vacuum magnetic permeability, unit N / A 2 ; m1 is the magnetic dipole moment of the first magnet 400, in A·m 2 ; m2 is the magnetic dipole moment of the second magnet 500, in A·m 2 ; d is the vertical distance between the first magnet 400 and the second magnet 500, unit: m.

[0048] In step S2, the linear relationship between the amplitude and the excitation voltage, and the relationship between the amplitude and the spacing satisfy:

[0049] Aw=kV

[0050] Aw=η×d

[0051] Wherein: Aw is the surface amplitude of the piezoelectric ceramic, k is the electromechanical coupling coefficient; V is the excitation voltage applied to the piezoelectric block 100; η is the proportional factor of the amplitude and spacing desired in the design; d is the vertical spacing between the first magnet 400 and the second magnet 500. In this embodiment, η can be understood as the ratio between the amplitude height and the spacing. This ratio is mainly used to optimize efficiency, force transmission, stability, system stiffness and material limit to ensure better driving performance; preferably, η is arbitrarily selected within the range of 0.1-1.

[0052] In the present invention, the thickness of the first magnet 400 is 0.05 mm to 10 mm; the thickness of the second magnet 500 is 0.05 mm to 10 mm; and the vertical distance between the first magnet 400 and the second magnet 500 is 0.1 mm to 5 mm.

[0053] In the present invention, the first magnet 400 and the second magnet 500 are made of the same material, which is neodymium iron boron, samarium cobalt or barium ferrite.

[0054] Specifically, the characteristics of neodymium iron boron (NdFeB) are: high remanence, strong coercivity, high magnetic density, and most commonly used at room temperature. The characteristics of samarium cobalt (SmCo) are: good high temperature stability and stable magnetic properties; the characteristics of barium ferrite (Ferrite) are: low magnetic properties but cheap, corrosion-resistant, suitable for cost-sensitive applications.

[0055] In the present invention, the excitation voltage is 1V to 1000V.

[0056] The first magnets 400 and the second magnets 500 are each one or more groups, and in each group, the ratio of the number of first magnets 400 to each group of second magnets 500 is 2:3; multiple first magnets 400 are arranged at equal intervals on the piezoelectric block 100, and multiple second magnets 500 are arranged at equal intervals on the driven component 300.

[0057] The center distance between two adjacent first magnets 400 is L=λ; the center distance between two adjacent second magnets 500 is S=λ / 2.

[0058] The present invention also provides a piezoelectric drive system for realizing a piezoelectric drive method based on magnetic levitation. The piezoelectric drive system includes a piezoelectric block 100, a stator 200 and a driven component 300. The stator 200 is arranged on the piezoelectric block 100; a first magnet 400 is arranged on the outer surface of the stator 200; a second magnet 500 is arranged on the driven component 300, the first magnet 400 and the second magnet 500 are facing each other and staggered, and the magnetic properties of the first magnet 400 and the second magnet 500 on a surface that contacts each other are the same.

[0059] In the present invention, the first magnets 400 and the second magnets 500 are each one or more groups, and the ratio of the number of each group of first magnets 400 to each group of second magnets 500 is 2:3; multiple groups of first magnets 400 are arranged at equal intervals on the piezoelectric block 100, and multiple groups of second magnets 500 are arranged at equal intervals on the driven component 300.

[0060] The technical solution protected by the present invention is described in detail below with specific embodiments.

[0061] Example 1

[0062] The piezoelectric driving method based on magnetic suspension provided in this embodiment includes the following steps:

[0063] S1. A first magnet 400 is disposed on the outer surface of the stator 200 on the piezoelectric block 100; a second magnet 500 is disposed on the outer surface of the driven component 300; the first magnet 400 and the second magnet 500 are disposed opposite to each other, and the magnetic properties of the first magnet 400 and the second magnet 500 on the surface in contact with each other are the same.

[0064] See also Figure 2The first magnet 400 and the second magnet 500 are each a group, and in this group, the number ratio of the first magnet 400 to the second magnet 500 is 2:3; specifically, there are two first magnets 400 and three second magnets 500. The two first magnets 400 are arranged at equal intervals on the piezoelectric block 100, and the three second magnets 500 are arranged at equal intervals on the driven component 300.

[0065] Preferably, the stator 200 is a protrusion disposed on the piezoelectric block 100 , and since there are two first magnets 400 , two protrusions are disposed.

[0066] In this embodiment, the upper surface of the protrusion is adapted to the structure of the first magnet 400 and is both ellipsoidal.

[0067] S2. In this embodiment, the piezoelectric block 100 generates an amplitude when stimulated by the external environment. The amplitude generated by the piezoelectric block 100 is transmitted to the driven component 300 through the magnetic repulsion force generated between the first magnet 400 and the second magnet 500, driving the driven component 300 to generate displacement and force in a suspended state.

[0068] Preferably, when the piezoelectric block 100 is stimulated by external factors to generate an amplitude, the amplitude causes the stator 200 on the piezoelectric block 100 to generate displacement and force. Since the first magnet 400 arranged on the surface of the stator 200 and the second magnet 500 arranged on the driven component 300 have the same polarity, based on the characteristic that like charges repel each other, a magnetic repulsive force is generated between the first magnet 400 and the second magnet 500. The displacement and force generated by the piezoelectric block 100 are transmitted through the magnetic repulsive force, and in a suspended state, the transmitted displacement and force act on the driven component 300, so that the driven component 300 generates displacement and force, thereby driving the driven component 300 to move.

[0069] Preferably, the wavelength of the amplitude generated by the piezoelectric block 100 is set to λ. In order to realize the stator 200 continuously pushing the driven component 300 to generate driving, the center distance S between two adjacent second magnets 500 is S=λ / 2; the center distance between two adjacent first magnets 400 is the wavelength to generate a stable traveling wave mode.

[0070] In this embodiment, in order to ensure that the generated magnetic repulsion force can enable the stator 200 to continuously push the driven component 300, the magnetic repulsion force satisfies the following relationship:

[0071] F=(3μ0×m1×m2) / 4πd 4

[0072] Where: F is the magnetic repulsion, unit N; μ0 is the vacuum magnetic permeability, unit N / A 2 ; m1 is the magnetic dipole moment of the first magnet 400, in A·m 2; m2 is the magnetic dipole moment of the second magnet 500, in A·m 2 ; d is the vertical distance between the first magnet 400 and the second magnet 500, unit: m.

[0073] In this embodiment, there is a linear relationship between the amplitude and the excitation voltage, specifically satisfying the following relationship:

[0074] Aw=kV

[0075] Wherein: Aw is the surface amplitude of the piezoelectric ceramic, k is the electromechanical coupling coefficient; V is the excitation voltage applied to the piezoelectric block 100.

[0076] In this embodiment, the relationship between the amplitude and the spacing satisfies:

[0077] Aw=η×d

[0078] Wherein: Aw is the surface amplitude of the piezoelectric ceramic, η is the proportional factor of the desired amplitude and spacing; d is the vertical spacing between the first magnet 400 and the second magnet 500.

[0079] In this embodiment, η can be understood as the ratio between the amplitude height and the spacing. This ratio is mainly used to optimize efficiency, force transmission, stability, system stiffness and material limits to ensure better driving performance; preferably, η takes any value in the range of 0.1-1.

[0080] In this embodiment, the piezoelectric block 100 is a rectangular block made of piezoelectric ceramics, and the size of the piezoelectric block 100 is: 10 mm (length) × 10 mm (width) × 0.5 mm (thickness).

[0081] In this embodiment, the thickness (H1) of the first magnet 400 is 1 mm; the thickness (H2) of the second magnet 500 is 1 mm; and the vertical distance (d) between the first magnet 400 and the second magnet 500 is 2 mm. At this time, while ensuring sufficient magnetic repulsion, it is beneficial for the piezoelectric ceramic to achieve effective vibration propulsion at a relatively low voltage.

[0082] In this embodiment, the first magnet 400 and the second magnet 500 are made of the same material, which is neodymium iron boron. Magnets of this material have high remanence and strong coercive force, and can obtain high magnetic force density.

[0083] In this embodiment, the excitation voltage is 1V to 1000V. The range of the excitation voltage needs to be considered in combination with the piezoelectric ceramic material properties of the piezoelectric block 100, the required amplitude, wavelength, and the desired linear speed of the motor. Preferably, the excitation voltage can be selected within 1V to 100V; if a larger amplitude or magnetic repulsion is required, the excitation voltage can be increased to 100V to 1000V.

[0084] See also Figure 3 and Figure 4 Based on the above preferred scheme, when the piezoelectric block 100 generates an amplitude when subjected to an external excitation voltage and drives the stator 200 to vibrate according to the amplitude, a magnetic repulsive force is generated between the first magnet 400 arranged on the surface of the stator 200 and the second magnet 500 arranged on the driven component 300 under the same polarity, so that the stator 200 pushes the driven component 300 to move continuously in a suspended state, thereby avoiding the friction loss generated by the contact piezoelectric drive device and improving the service life of the piezoelectric drive.

[0085] Example 2

[0086] This embodiment provides a piezoelectric driving system, which is used to implement the piezoelectric driving method based on magnetic suspension in Embodiment 1.

[0087] The piezoelectric driving system provided in this embodiment includes a piezoelectric block 100, a stator 200 and a driven component 300, wherein the stator 200 is arranged on the piezoelectric block 100; a first magnet 400 is arranged on the outer surface of the stator 200; a second magnet 500 is arranged on the driven component 300, the first magnet 400 and the second magnet 500 are facing each other and staggered, and the magnetic properties of the first magnet 400 and the second magnet 500 on a surface that contacts each other are the same.

[0088] In this embodiment, the piezoelectric block 100 is a rectangular block made of piezoelectric ceramics. The size range of the piezoelectric block 100 is: thickness (H) is 0.2 mm to 1 mm, length (L) is 5 mm to 50 mm, and width (W) is 5 mm to 20 mm.

[0089] Specifically, the thickness of the piezoelectric block 100 is determined according to the operating frequency, and the length of the piezoelectric block 100 can be appropriately enlarged or reduced according to the design frequency and vibration mode. Preferably, the size of the piezoelectric block 100 is: 10mm (length) × 10mm (width) × 0.5mm (thickness), which meets the requirements of small and medium-sized piezoelectric drive devices.

[0090] See also Figure 2 The first magnet 400 and the second magnet 500 are each a group, and in this group, the number ratio of the first magnet 400 to the second magnet 500 is 2:3. The two first magnets 400 are arranged at equal intervals on the piezoelectric block 100, and the three second magnets 500 are arranged at equal intervals on the driven component 300.

[0091] Preferably, the stator 200 is a protrusion disposed on the piezoelectric block 100 , and since there are two first magnets 400 , two protrusions are disposed.

[0092] In this embodiment, the upper surface of the protrusion is adapted to the structure of the first magnet 400 and is both ellipsoidal.

[0093] Preferably, the driven component 300 is a slide rod, and may also be other rotatable or movable components of the rotor.

[0094] In this embodiment, the thickness (H1) of the first magnet 400 is 1 mm; the thickness (H2) of the second magnet 500 is 1 mm; and the vertical distance (d) between the first magnet 400 and the second magnet 500 is 2 mm. At this time, while ensuring sufficient magnetic repulsion, it is beneficial for the piezoelectric ceramic to achieve effective vibration propulsion at a relatively low voltage.

[0095] In this embodiment, the first magnet 400 and the second magnet 500 are made of the same material, which is neodymium iron boron. Magnets of this material have high remanence and strong coercive force, and can obtain high magnetic force density.

[0096] In this embodiment, when the driven component 300 is a sliding rod, a guide mechanism can also be set on the outside of the driven component 300, such as a ceramic guide sleeve (zirconium oxide or silicon nitride) or a metal precision guide rail (stainless steel) to improve the movement accuracy and straightness. The size of the guide mechanism is fine-tuned with the diameter of the driven component 300. For example, when the diameter of the sliding rod is 3 to 5 mm, the inner diameter of the guide sleeve or the inner diameter of the guide rail has a corresponding slight over-tolerance fit.

[0097] In this embodiment, a coupling or a connector (made of PEEK or aluminum alloy) is added to the end of the driven component 300 to connect an external load. The size of the coupling depends on the application requirements; preferably, the length of the coupling is 5 mm to 10 mm.

[0098] In the above-mentioned embodiment 1 and embodiment 2, each parameter can also be replaced, and the thickness of the first magnet 400, the thickness of the second magnet 500, the vertical spacing between the first magnet 400 and the second magnet 500, and the excitation voltage can be arbitrarily selected in the range of 0.05mm-10mm, 0.05mm-10mm, 0.1mm-5mm and 1V-1000V. When each parameter is replaced, the first magnet 400 and the second magnet 500 can generate magnetic repulsion due to the same polarity, and the displacement and force generated by the piezoelectric block can be transmitted through the magnetic repulsion, and then the transmitted displacement and force are applied to the driven component in a non-contact suspension state, so that the driven component generates displacement and force, thereby promoting the driven component 300 to be continuously driven.

[0099] In the above-mentioned Embodiment 1 and Embodiment 2, two first magnets and three second magnets are designed as one group, and then multiple groups are set, multiple first magnets are arranged at equal intervals on the piezoelectric block, and multiple second magnets are arranged at equal intervals on the driven component. The arrangement spacing refers to Embodiment 1 and Embodiment 2.

[0100] The piezoelectric drive system and drive method provided by the present invention transmit the displacement and force generated by the piezoelectric block through magnetic repulsion, thereby achieving continuous drive, avoiding friction loss, and improving the life of the piezoelectric drive, and can be used in various piezoelectric drive scenarios.

[0101] Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments, and are not intended to limit the scope of protection of the present invention. Based on the described embodiments of the present invention, any modifications, equivalent substitutions, improvements, etc. made by ordinary technicians in the field without creative work should be included in the scope of protection of the present invention.

Claims

1. A piezoelectric driving method based on magnetic levitation, characterized in that: The following steps are involved: S1. A first magnet (400) is arranged on the outer surface of a stator (200) on a piezoelectric block (100); a second magnet (500) is arranged on the outer surface of a driven component (300); the first magnet (400) and the second magnet (500) are arranged facing each other, and the polarity of the surface of the first magnet (400) and the second magnet (500) that are in contact with each other is the same; S2. The piezoelectric block (100) generates an amplitude when stimulated by the outside world. The amplitude generated by the piezoelectric block (100) is transmitted to the driven component (300) through the magnetic repulsive force generated between the first magnet (400) and the second magnet (500), thereby pushing the driven component (300) to generate displacement and force in a suspended state.

2. The piezoelectric driving method based on magnetic levitation according to claim 1, characterized in that: In step S2, the magnetic repulsion satisfies the following relationship: F=(3μ0×m1×m2) / 4πd 4 Where: F is the magnetic repulsion, unit N; μ0 is the vacuum magnetic permeability, unit N / A 2 ; m1 is the magnetic dipole moment of the first magnet (400), unit A·m 2 ; m2 is the magnetic dipole moment of the second magnet (500), unit A·m 2 ; d is the vertical distance between the first magnet (400) and the second magnet (500), unit: m.

3. The piezoelectric driving method based on magnetic levitation according to claim 1, characterized in that: In step S2, the linear relationship between the amplitude and the excitation voltage, and the relationship between the amplitude and the spacing satisfy: Aw=kV Aw=η×d Wherein: Aw is the amplitude generated by the piezoelectric ceramic, k is the electromechanical coupling coefficient; V is the excitation voltage applied to the piezoelectric block (100); η is the proportionality factor between the amplitude and the spacing; d is the vertical spacing between the first magnet (400) and the second magnet (500).

4. The piezoelectric driving method based on magnetic levitation according to claim 2, characterized in that: The thickness of the first magnet (400) is 0.05 mm to 10 mm; the thickness of the second magnet (500) is 0.05 mm to 10 mm; and the vertical distance between the first magnet (400) and the second magnet (500) is 0.1 mm to 5 mm.

5. The piezoelectric driving method based on magnetic levitation according to claim 2, characterized in that: The first magnet (400) and the second magnet (500) are made of the same material, which is neodymium iron boron, samarium cobalt or barium ferrite.

6. The piezoelectric driving method based on magnetic levitation according to claim 1, characterized in that: The excitation voltage is 1V to 1000V.

7. The piezoelectric driving method based on magnetic levitation according to claim 1, characterized in that: The first magnets (400) and the second magnets (500) are each one or more groups, and in each group, the ratio of the number of the first magnets (400) to the number of the second magnets (500) is 2:3, the plurality of first magnets (400) are arranged at equal intervals on the piezoelectric block (100), and the plurality of second magnets (500) are arranged at equal intervals on the driven component (300).

8. The piezoelectric driving method based on magnetic levitation according to claim 7, characterized in that: The center distance between two adjacent first magnets (400) is L=λ; the center distance between two adjacent second magnets (500) is S=λ / 2.

9. A piezoelectric drive system for implementing the piezoelectric drive method based on magnetic levitation according to claim 1, characterized in that: The piezoelectric drive system comprises: The invention comprises a piezoelectric block (100), a stator (200) and a driven component (300), wherein the stator (200) is arranged on the piezoelectric block (100); a first magnet (400) is arranged on the outer surface of the stator (200); a second magnet (500) is arranged on the driven component (300), the first magnet (400) and the second magnet (500) are facing each other and are staggered, and the first magnet (400) and the second magnet (500) have the same magnetic properties on the surface where they contact each other.

10. The piezoelectric drive system according to claim 9, characterized in that: The first magnets (400) and the second magnets (500) are each one or more groups, and in each group, the ratio of the number of the first magnets (400) to the number of the second magnets (500) is 2:3, the plurality of first magnets (400) are arranged at equal intervals on the piezoelectric block (100), and the plurality of second magnets (500) are arranged at equal intervals on the driven component (300).

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