Magnetic suspension voice coil motor

Abstract

The utility model belongs to the technical field of semiconductor equipment, and provides a magnetic suspension voice coil motor which comprises a first assembly and a second assembly which are spaced from each other, and the first assembly comprises a first magnet, a second magnet and a third magnet which are sequentially arranged in the z direction with the axial direction of the first assembly as the z direction. The second assembly comprises first back iron and a first coil which are coaxial with the first assembly, the first back iron is located between the first magnet and the second magnet, the first coil is located on the side, away from the first magnet, of the first back iron, and the magnetizing direction of the first magnet and the magnetizing direction of the second magnet are the z direction. Magnetic levitation force and Lorentz force are generated between the second assembly and the first assembly, the gravity of the vertical micropositioner and the reverse acting force of the reed can be compensated through the magnetic levitation force, and the driving effect on the vertical micropositioner can be achieved through the Lorentz force. The vertical resultant force of the magnetic levitation force and the Lorentz force is linearly changed within the displacement range of the vertical micropositioner, so that the magnetic levitation voice coil motor has the characteristic of constant rigidity, and the heating problem of the motor is solved.

Description

Technical Field

[0001] This application relates to the field of semiconductor equipment technology, and in particular to a magnetic levitation voice coil motor. Background Technology

[0002] In the field of semiconductor manufacturing and inspection, the workpiece stage not only needs to facilitate device transfer with the semiconductor transport system but also needs to achieve precise positioning of the supported semiconductor devices. The workpiece stage is equipped with a vertical micro-stage responsible for achieving precise positioning of semiconductor devices (such as silicon wafers) along three axes: vertical, x-axis, and y-axis. However, with technological advancements, higher requirements have been placed on the motion precision control of the vertical micro-stage.

[0003] Vertical micro-motion stages typically employ a three-point or four-point actuator layout. To ensure vertical output performance, reeds are used as guiding elements for vertical motion and decoupling elements for pitch and yaw. To improve the control accuracy of the vertical micro-motion stage, the actuator not only needs to provide vertical driving force for the movement of the stage, but also needs to compensate for the weight of the stage and the reaction force of the reeds.

[0004] Currently, the vertical motion of a vertical micro-motion stage typically employs a combination of a gravity compensation device and a voice coil motor to improve its control accuracy. The gravity compensation device uses principles such as air levitation or magnetic levitation to compensate for the gravity of the vertical drive load of the micro-motion stage through constant gravity compensation. The voice coil motor, as the vertical actuator, provides the reaction force of the reed and the driving force for the vertical motion of the micro-motion stage. However, in practical applications, the spring force of the reed is linearly related to the vertical displacement. Within different stroke ranges, the reaction force of the reed varies, affecting the output force of the voice coil motor. This leads to increased heat generation in the voice coil motor, resulting in poor control accuracy for the vertical micro-motion stage equipped with a voice coil motor. Utility Model Content

[0005] In view of the shortcomings of the prior art described above, the purpose of this application is to provide a magnetic levitation voice coil motor to solve the problem that the increased heat generation of the voice coil motor in the prior art leads to poor control accuracy of the vertical micro-motion stage equipped with the voice coil motor.

[0006] To achieve the above and other related objectives, this application provides a magnetic levitation voice coil motor, including a first component and a second component spaced apart from each other, with the axial direction of the first component as the z-direction, and the first component and the second component being able to move relative to each other along the z-direction;

[0007] The first component includes a first magnet, a second magnet, and a third magnet arranged coaxially and spaced apart along the z-direction. The second component includes a first back iron and a first coil arranged coaxially with the first component. The first back iron is located between the first magnet and the second magnet, and the first coil is located on the side of the first back iron away from the first magnet. The magnetization direction of the first magnet and the second magnet is the z-direction.

[0008] Optionally, the first component further includes a third back iron, in which a first through hole is provided, the first through hole penetrating the third back iron along the z-direction, and the first magnet, the first back iron, the second magnet and the third magnet are all located within the first through hole.

[0009] Optionally, the first component further includes a fourth back iron, which is located between the second magnet and the third magnet and is connected to the second magnet and the third magnet, respectively.

[0010] Optionally, the first component further includes a fifth back iron, which is connected to the side of the first magnet away from the first back iron.

[0011] Optionally, the fourth back iron and the fifth back iron are both spaced apart from the third back iron.

[0012] Optionally, the fourth back iron is spaced apart from the third back iron, and the fifth back iron is connected to the sidewall of the first through hole.

[0013] Optionally, both the fourth back iron and the fifth back iron are connected to the sidewall of the first through hole.

[0014] Optionally, the magnetic levitation voice coil motor is provided with a second through hole coaxially arranged with the first component, and the second through hole penetrates the first component and the first back iron along the z direction.

[0015] Optionally, the first coil is sleeved on the outside of the third magnet, and the magnetization direction of the third magnet is the z-direction.

[0016] Optionally, the first component further includes a second back iron, which is connected to the side of the third magnet away from the second magnet.

[0017] Optionally, the first component further includes a fourth magnet coaxially disposed with the first magnet, the fourth magnet being located on the side of the first magnet away from the first back iron;

[0018] The second component further includes a second coil coaxially arranged with the first component, the second coil being sleeved on the outside of the fourth magnet, and the magnetization direction of the fourth magnet being the z-direction.

[0019] Optionally, the first component further includes a sixth back iron, which is connected to the side of the fourth magnet away from the first back iron.

[0020] Optionally, the third magnet is sleeved on the outside of the first coil, and the magnetization direction of the third magnet is its radial direction;

[0021] The magnetic levitation voice coil motor is provided with a third through hole coaxially arranged with the first component, and the third through hole passes through the first magnet, the second magnet and the third magnet.

[0022] Optionally, the first component further includes a fourth magnet coaxially disposed with the first magnet, the fourth magnet being located on the side of the first magnet away from the first back iron;

[0023] The second component further includes a second coil coaxially arranged with the first component, and the fourth magnet is sleeved on the outside of the second coil, and the magnetization direction of the fourth magnet is its radial direction.

[0024] As described above, the magnetic levitation voice coil motor provided in this application has at least the following beneficial effects:

[0025] The magnetic levitation voice coil motor of this application comprises a first component consisting of a first magnet, a second magnet, and a third magnet, and a second component consisting of a first back iron and a first coil. The magnetic levitation force generated between the second component and the first component can compensate for the gravity of the vertical micro-motion stage and the reverse force of the reed. The Lorentz force generated between the second component and the first component can drive the vertical micro-motion stage. The third magnet can adjust the magnitude of the downward attraction force on the first back iron, thereby controlling the vertical output force of the magnetic levitation voice coil motor.

[0026] Furthermore, within different vertical stroke ranges, the resultant force of the magnetic levitation force and the Lorentz force in the magnetic levitation voice coil motor of this application exhibits a linear variation within a large displacement range of the vertical micro-motion stage, thereby enabling the magnetic levitation voice coil motor to possess constant stiffness characteristics, thus effectively improving the heating problem of the magnetic levitation voice coil motor. Based on the constant stiffness characteristics of the magnetic levitation voice coil motor, the forces applied by the magnetic levitation voice coil motor and the reed to the vertical micro-motion stage can be of the same magnitude but opposite in direction. That is, the vertical resultant force of the two acting together on the vertical micro-motion stage tends to be a zero stiffness curve, improving the positioning accuracy of the vertical micro-motion stage.

[0027] In addition, the magnetic levitation voice coil motor of this application realizes the function of constant stiffness gravity compensation by only using the first magnet, the second magnet, the third magnet and the first back iron, and can realize the function of constant stiffness vertical drive by combining the first coil. It has a simple structure and occupies little space.

[0028] In summary, the magnetic levitation voice coil motor of this application has the characteristics of low heat generation, low power consumption, simple structure, small space occupation, and constant stiffness within the stroke range. It realizes precise positioning of the vertical micro-motion stage and improves the overall integration and control accuracy of the equipment. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 The diagram shown is a structural schematic of a magnetic levitation voice coil motor provided in an embodiment of this application.

[0031] Figure 2 The diagram shown is a structural schematic of a magnetic levitation voice coil motor with a third back iron provided in Embodiment 1 of this application.

[0032] Figure 3 The diagram shown is a structural schematic of a magnetic levitation voice coil motor with a fourth back iron provided in Embodiment 1 of this application.

[0033] Figures 4 to 6 The diagrams shown are schematic diagrams of three different magnetic levitation voice coil motors, each with a third to a fifth back iron, provided in Embodiment 1 of this application.

[0034] Figure 7 and Figure 8 The diagrams show two different magnetic levitation voice coil motors with a second back iron provided in Embodiment 1 of this application.

[0035] Figure 9 Displayed as Figure 8 The diagram shows the magnetic field lines distribution of a magnetic levitation voice coil motor.

[0036] Figure 10 Displayed as Figure 8 The diagram shows the force-displacement curve of a magnetic levitation voice coil motor.

[0037] Figure 11 Displayed as Figure 8 The diagram shows the relationship between the vertical resultant force of the magnetic levitation voice coil motor and the reverse force of the reed and the displacement.

[0038] Figures 12 to 14 The diagrams show three different magnetic levitation voice coil motors with a fourth magnet and a second coil, as provided in Embodiment 2 of this application.

[0039] Figure 15 Displayed as Figure 14 The diagram shows the force-displacement curve relationship of a magnetic levitation voice coil motor.

[0040] Figure 16 Displayed as Figure 14 The diagram shows the force-displacement relationship between the upward and downward attraction forces acting on the first back iron in the magnetic levitation voice coil motor.

[0041] Figures 17 to 19 The diagrams shown are schematic diagrams of three different magnetic levitation voice coil motors provided in Embodiment 3 of this application.

[0042] Figure 20 The diagram shown is a structural schematic of a magnetic levitation voice coil motor provided in Embodiment 4 of this application.

[0043] Figure 21 The diagram shown is a structural schematic of another magnetic levitation voice coil motor provided in Embodiment 4 of this application.

[0044] Figure 22 Displayed as Figure 21 The diagram shows the force-displacement curve relationship of a magnetic levitation voice coil motor.

[0045] Figure 23 The diagram shown is a top view of the fourth magnet along the z-direction provided in Embodiment 4 of this application.

[0046] Figure 24 The diagram shown is a structural schematic of a magnetic levitation voice coil motor provided in Embodiment 5 of this application.

[0047] Illustration of reference numerals in the attached diagram:

[0048] 10. First component; 111. First magnet; 112. Second magnet; 113. Third magnet; 114. Fourth magnet; 121. Second back iron; 122. Third back iron; 1221. First through hole; 123. Fourth back iron; 124. Fifth back iron; 125. Sixth back iron; 20. Second component; 211. First back iron; 2111. Thickness gradient zone; 221. First coil; 222. Second coil; 311. Second through hole; 312. Third through hole. Detailed Implementation

[0049] To make the technical objectives, technical solutions, and technical effects of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0051] In the description of this application, it should be noted that the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with an implementation or example, which are included in at least one implementation or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same implementation or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more implementations or examples.

[0052] This application provides a magnetic levitation voice coil motor, referring to... Figure 1 It includes a first component 10 and a second component 20 arranged at intervals between each other, with the axis of the first component 10 as the z-direction, and the first component 10 and the second component 20 can move relative to each other in the z-direction.

[0053] The first component 10 includes a first magnet 111, a second magnet 112, and a third magnet 113, which are coaxially arranged along the z-direction and spaced apart sequentially. The second component 20 includes a first back iron 211 and a first coil 221, which are coaxially arranged with the first component 10. The first back iron 211 is located between the first magnet 111 and the second magnet 112, and the first coil 221 is located on the side of the first back iron 211 away from the first magnet 111. The magnetization direction of both the first magnet 111 and the second magnet 112 is the z-direction. The relative positions of the first magnet 111, the second magnet 112, and the third magnet 113 remain unchanged, as does the relative position of the first coil 221 and the first back iron 211.

[0054] The first magnet 111 exerts an upward attractive force on the first back iron 211, and the second magnet 112 exerts a downward attractive force on the first back iron 211. In the magnetic levitation voice coil motor, the resultant force of the upward and downward attractive forces on the first back iron 211 along the z-direction with other forces is denoted as the magnetic levitation force. Within the stroke range of the magnetic levitation voice coil motor, the magnetic levitation force has a linear relationship with the displacement. Therefore, the magnetic levitation force can compensate for the gravity of the vertical micro-motion stage and the reverse force of the reed. Among them, the other forces in the magnetic levitation force of the first back iron 211 can be understood as: the forces exerted on the first back iron 211 by other components other than the first magnet 111 and the second magnet 112 through the magnetic field; for example, when other back irons and / or magnet structures are also provided in the magnetic levitation voice coil motor, the above-mentioned other forces also include the forces exerted on the first back iron 211 by other back irons and / or magnet structures through the magnetic field.

[0055] The magnetic field generated by the third magnet 113 enhances or cancels the magnetic field generated by the second magnet 112, increasing or decreasing the downward attraction force on the first back iron 211, thereby affecting the vertical compensation force output by the magnetic levitation voice coil motor and controlling the vertical output force of the magnetic levitation voice coil motor. The first magnet 111, the second magnet 112, and the third magnet 113 generate magnetic fields in the surrounding space. When current is passed through the first coil 221, the first coil 221 cuts the magnetic field and generates a Lorentz force. The Lorentz force can drive the vertical micro-motion stage and also vertically position the movers in the first component 10 and the second component 20. The amplitude of the Lorentz force is related to the amplitude of the input current in the first coil 221.

[0056] In use, within different vertical stroke ranges, the vertical magnetic levitation force generated by the magnetic levitation voice coil motor changes linearly over a large displacement range. The reed is positioned between the mover of the magnetic levitation voice coil motor and the external load. The reed's reverse force also has a linear relationship with the displacement change. By adjusting the equivalent stiffness of the magnetic levitation voice coil motor, the forces applied to the vertical micro-motion stage by the magnetic levitation voice coil motor and the reed in this application can be made equal in magnitude and opposite in direction. That is, the resultant force of the two acting together on the vertical micro-motion stage tends to be a zero stiffness curve, enabling the magnetic levitation voice coil motor to accurately compensate for the reed's reverse force and the weight of the vertical micro-motion stage without external energy input. Furthermore, the vertical resultant force of the vertical magnetic levitation force and the Lorentz force generated by the magnetic levitation voice coil motor also has a linear relationship over a large displacement range, giving the magnetic levitation voice coil motor constant stiffness characteristics. This effectively improves the heating problem of the magnetic levitation voice coil motor, improves the compensation accuracy for the reed's reverse force and the weight of the vertical micro-motion stage, and enhances the positioning accuracy of the vertical micro-motion stage.

[0057] To provide a more detailed explanation of the magnetic levitation voice coil motor of this application, the technical solution of this application will be described below in conjunction with specific embodiments. It should be noted that, unless otherwise specified, the technical features and solutions in the following embodiments can be combined with each other.

[0058] Example 1

[0059] Reference Figure 1 This embodiment provides a magnetic levitation voice coil motor, including a first component 10 and a second component 20 arranged at intervals between each other. With the axial direction of the first component 10 as the z-direction, the first component 10 and the second component 20 can move relative to each other in the z-direction.

[0060] The first component 10 includes a first magnet 111, a second magnet 112, and a third magnet 113 arranged coaxially and spaced apart from each other along the z-direction. The second component 20 includes a first back iron 211 and a first coil 221 arranged coaxially with the first component 10. The first back iron 211 is located between the first magnet 111 and the second magnet 112, and the first coil 221 is located on the side of the first back iron 211 away from the first magnet 111. The relative positions of the first back iron 211 and the first coil 221 remain unchanged, as do the relative positions of the first magnet 111, the second magnet 112, and the third magnet 113. These relative positions can be maintained by a bracket or other suitable means. The magnetization direction of the first magnet 111 and the second magnet 112 is along the z-direction. The first magnet, the second magnet 112, and the third magnet 113 can be permanent magnets made of materials such as iron, aluminum, nickel, and cobalt, or magnetic structures made of other suitable materials.

[0061] In an optional embodiment, the second component 20 further includes a connector, which is connected to the first back iron 211 and the first coil 221 respectively, so that the relative position of the first back iron 211 and the first coil 221 remains unchanged. The first coil 221 can be directly connected to the connector or connected to the connector through a coil bracket.

[0062] In this embodiment, the first magnet 111, the second magnet 112, and the third magnet 113 constitute the first component 10, and the first back iron 211 and the first coil 221 constitute the second component 20. The magnetic levitation force generated between the second component 20 and the first component 10 can compensate for the gravity of the vertical micro-motion stage and the reverse force of the reed. The Lorentz force generated between the second component 20 and the first component 10 can drive the vertical micro-motion stage. The third magnet 113 can adjust the magnitude of the downward attraction force on the first back iron 211, thereby controlling the vertical output force of the magnetic levitation voice coil motor.

[0063] In this embodiment, refer to Figure 2 The first component 10 also includes a third back iron 122, in which a first through hole 1221 is provided. The first through hole 1221 extends through the third back iron 122 along the z-direction. The first magnet 111, the first back iron 211, the second magnet 112, and the third magnet 113 are all located within the first through hole 1221. The relative positions of the third back iron 122 with the first magnet 111, the second magnet 112, and the third magnet 113 remain unchanged. Optionally, the third back iron 122 may be, for example, a cylindrical structure, coaxially arranged with the first back iron 211. The cavity within the cylindrical structure of the third back iron 122 forms the first through hole 1221, which is coaxially arranged with the third back iron 122. The third back iron 122 may be made of a high-permeability material. By providing the third back iron 122, it is helpful to improve the magnetic field distribution and enhance the performance of the magnetic levitation voice coil motor.

[0064] Reference Figure 3 The first component 10 may also include a fourth back iron 123, which is located between the second magnet 112 and the third magnet 113. The fourth back iron 123 may be made of a high magnetic permeability material or other suitable materials to improve the magnetic field distribution between the second magnet 112 and the third magnet 113 and in the surrounding space, enhance the interference effect of the magnetic field generated by the second magnet 112 on the magnetic field generated by the third magnet 113, and thus enhance the control effect on the downward attraction force on the first back iron 211.

[0065] In an optional embodiment, the fourth back iron 123 is connected to the second magnet 112 and the third magnet 113 respectively. Optionally, the fourth back iron 123 is fixedly connected to both the second magnet 112 and the third magnet 113, which can be achieved by bonding or other suitable methods. The fourth back iron 123 can be spaced apart from the third back iron 122, or the fourth back iron 123 can be connected to the sidewall of the first through hole 1221, or the fourth back iron 123 can be integrated with the third back iron 122.

[0066] Reference Figure 4 The first component 10 may also include a fifth back iron 124, which is located on the side of the first magnet 111 away from the first back iron 211. The fifth back iron 124 may be made of a high magnetic permeability material or other suitable material to improve the magnetic field distribution in the surrounding space and improve the performance of the magnetic levitation voice coil motor.

[0067] In an optional embodiment, the fifth back iron 124 is connected to the first magnet 111. Optionally, the fifth back iron 124 and the first magnet 111 are fixedly connected, which can be achieved by adhesive bonding or other suitable methods. The fifth back iron 124 can be spaced apart from the third back iron 122, or the fifth back iron 124 can be connected to the sidewall of the first through hole 1221, or the fifth back iron 124 and the third back iron 122 can be integrated into one structure.

[0068] In an optional embodiment, the fifth back iron 124 has a groove on the side facing the first magnet 111 for installing the first magnet 111. Specifically, for example, a groove with a depth of 0.5 mm or other suitable size can be opened to place the first magnet 111 in the groove so as to facilitate the installation of the first magnet 111.

[0069] In an optional embodiment, the fourth back iron 123 and the fifth back iron 124 are both spaced apart from the third back iron 122, and the external load can be set above and / or below the first back iron 211 along the z direction, which improves the ease of use of the magnetic levitation voice coil motor.

[0070] In an optional embodiment, refer to Figure 5 The fourth back iron 123 and the third back iron 122 are spaced apart from each other, and the fifth back iron 124 is connected to the sidewall of the first through hole 1221, so that the relative positions of the third back iron 122, the fifth back iron 124, and the first magnet 111 remain unchanged. Optionally, the fifth back iron 124 is fixedly connected to the sidewall of the first through hole 1221, which can be achieved by adhesive bonding or other suitable methods.

[0071] In an optional embodiment, refer to Figure 6 The fourth back iron 123 and the fifth back iron 124 are both connected to the sidewall of the first through hole 1221, so that the relative positions of the third back iron 122, the fourth back iron 123, the second magnet 112, the fifth back iron 124, and the first magnet 111 remain unchanged. Optionally, the fourth back iron 123 and the fifth back iron 124 are both fixedly connected to the sidewall of the first through hole 1221, which can be achieved by adhesive bonding or other suitable methods.

[0072] Furthermore, the magnetic levitation voice coil motor is provided with a second through hole 311 coaxially arranged with the first component 10. The second through hole 311 passes through the first component 10 and the first back iron 211 along the z direction. By providing the second through hole 311, it is convenient to use connectors or other suitable methods to keep the relative position between the first coil 221 and the first back iron 211 unchanged, which facilitates the installation and use of the magnetic levitation voice coil motor.

[0073] In this embodiment, refer to Figures 1 to 6 The first coil 221 is sleeved on the outside of the third magnet 113, and the magnetization direction of the third magnet 113 is the z direction.

[0074] In an optional embodiment, refer to Figure 7 and Figure 8 The first component 10 also includes a second back iron 121, which is connected to the side of the third magnet 113 away from the second magnet 112. The second back iron 121 is used to improve the magnetic field distribution, improve the direction of the Lorentz force on the first coil 221, and increase the component of the Lorentz force along the z direction, so as to improve the performance of the magnetic levitation voice coil motor.

[0075] Figure 9 It shows Figure 8 The diagram shows the magnetic field lines inside a magnetic levitation voice coil motor. Figure 9 This is a half-section view of a magnetic levitation voice coil motor cut radially from its axis. The z-axis in the figure is the axis of the magnetic levitation voice coil motor. Figure 10 It shows Figure 8 The force-displacement curves of the magnetic levitation voice coil motor shown are as follows: the magnetization directions of the first magnet 111, the second magnet 112, and the third magnet 113 are all upward along the z-direction. The first magnet 111 has an upward attraction to the first back iron 211, the second magnet 112 has a downward attraction to the first back iron 211, and the magnetic field generated by the third magnet 113 can be superimposed with the magnetic field generated by the second magnet 112, thereby affecting the downward attraction of the first back iron 211.

[0076] Reference Figure 10 In a magnetic levitation voice coil motor, when the first magnet 111 and the second magnet 112 are symmetrically arranged along the z-direction about the first back iron 211, taking the position of the first back iron 211 at this time as the zero point, when the first back iron 211 moves towards the first magnet 111, its displacement is within... Figure 10 As the first back iron 211 moves in the positive direction along the horizontal axis and moves closer to the second magnet 112, its displacement is... Figure 10 Move along the negative horizontal axis. Figure 10In the diagram, curve 011 represents the downward attraction force and displacement of the second magnet 112 on the first back iron 211, curve 012 represents the upward attraction force and displacement of the first magnet 111 on the first back iron 211, and curve 013 represents the vertical magnetic levitation force (i.e., the resultant force of the upward attraction force, downward attraction force, and other magnetic field forces) experienced by the first back iron 211. According to simulation results, when the first back iron 211 approaches the first magnet 111 from the zero point, the upward attraction force gradually increases, and the downward attraction force gradually decreases, resulting in a larger upward vertical magnetic levitation force output by the magnetic levitation voice coil motor. Conversely, when the first back iron 211 approaches the second magnet 112 from the zero point, the upward attraction force gradually decreases, and the downward attraction force gradually increases, resulting in a larger downward vertical magnetic levitation force output by the magnetic levitation voice coil motor. Consequently, the vertical magnetic levitation force experienced by the first back iron 211 exhibits a linear variation trend with displacement within a relatively large vertical travel range around the zero point. For example… Figure 10 The vertical stroke range shown is from -1mm to 1mm.

[0077] Figure 10 In the diagram, curve 014 represents the Lorentz force acting on the first coil 221, with a thrust constant of approximately 5.8 N / A. This thrust constant represents the Lorentz force of the magnetic levitation voice coil motor under unit current input. Curve 015 represents the vertical resultant force of the vertical magnetic levitation force and the Lorentz force of the magnetic levitation voice coil motor versus displacement. Simulation results show that within the vertical stroke range, the vertical resultant force of the magnetic levitation voice coil motor exhibits a nearly linear variation with displacement. For example… Figure 10 Within the vertical stroke range of -1mm to 1mm shown, the linearity decreases beyond this range.

[0078] Figure 11 It shows Figure 8 The curves shown represent the vertical resultant force of the magnetic levitation force and Lorentz force of the magnetic levitation voice coil motor, as well as the reaction force and displacement of the reed. Figure 11 In the diagram, the short dashed line represents the curve of the reed's reaction force versus displacement, the long dashed line represents the curve of the vertical resultant force versus displacement of the magnetic levitation voice coil motor, and the solid line represents the curve of the resultant force versus displacement of both. According to simulation calculations, within the vertical stroke range of the magnetic levitation voice coil motor, for example… Figure 11 The vertical stroke range of -1mm to 1mm shown indicates that the stiffness of the reed is equal to or approximately equal to the equivalent stiffness of the vertical resultant force of the motor, but in opposite directions. This makes the resultant stiffness of the magnetic levitation voice coil motor and the reed approach zero, effectively improving the heating problem of the magnetic levitation voice coil motor and enhancing the positioning accuracy of the vertical micro-motion stage.

[0079] In summary, the magnetic levitation voice coil motor of this embodiment achieves the function of constant stiffness gravity compensation using only the first magnet 111, the second magnet 112, the third magnet 113, and the first back iron 211. Combined with the first coil 221, it can achieve the function of constant stiffness vertical drive. It has the characteristics of low heat generation, low power consumption, simple structure, small space occupation, and constant stiffness within the stroke range. It also improves the positioning accuracy of the vertical micro-motion stage and the overall integration and control accuracy of the equipment.

[0080] Example 2

[0081] This embodiment provides a magnetic levitation voice coil motor, which also includes a first component 10 and a second component 20. The similarities with Embodiment 1 will not be repeated. The difference is that in the magnetic levitation voice coil motor of this embodiment, the first component 10 also includes a fourth magnet 114, and the second component 20 also includes a second coil 222.

[0082] In this embodiment, refer to Figure 12 The fourth magnet 114 is coaxially arranged with the first magnet 111, located on the side of the first magnet 111 away from the first back iron 211. The second coil 222 is coaxially arranged with the first assembly 10, and is sleeved on the outside of the fourth magnet 114. The magnetization direction of the fourth magnet 114 is in the z-direction. The relative positions of the second coil 222, the first coil 221, and the first back iron 211 remain unchanged, for example, through a connector. The relative positions of the first magnet 111, the second magnet 112, the third magnet 113, and the fourth magnet 114 remain unchanged. By setting the fourth magnet 114 and the second coil 222, the strength of the distributed magnetic field within the magnetic levitation voice coil motor can be enhanced, increasing the magnetic levitation force and Lorentz force along the z-direction, thereby increasing the output thrust of the magnetic levitation voice coil motor. Furthermore, loads can be placed on both opposite sides of the magnetic levitation voice coil motor along the z-direction, improving ease of use.

[0083] In an optional embodiment, refer to Figure 13 and Figure 14 The first component 10 also includes a sixth back iron 125, which is located on the side of the fourth magnet 114 away from the first back iron 211. The second coil 222 is arranged around the outside of the sixth back iron 125. Optionally, the sixth back iron 125 is connected to the fourth magnet 114, for example, by bonding or other suitable means. The sixth back iron 125 can be used to improve the distribution of the magnetic field inside the magnetic levitation voice coil motor, increase the Lorentz force along the z-direction experienced by the second coil 222, and thus improve the motor performance.

[0084] Furthermore, referring to Figure 13The first component 10 also includes the second back iron 121, the third back iron 122, the fourth back iron 123 and the fifth back iron 124 in Embodiment 1, wherein the fourth back iron 123 and the fifth back iron 124 are spaced apart from the third back iron 122.

[0085] Furthermore, referring to Figure 14 The first component 10 also includes the second back iron 121, the third back iron 122, the fourth back iron 123, and the fifth back iron 124 as described in Embodiment 1. The fourth back iron 123 and the fifth back iron 124 are both connected to the sidewall of the first through hole 1221. The first coil 221 is located on the side of the fourth back iron 123 away from the first back iron 211, and the second coil 222 is located on the side of the fifth back iron 124 away from the first back iron 211. The fourth back iron 123 and the fifth back iron 124 can be fixedly connected to the third back iron 122 by adhesive bonding or other suitable methods, or the fourth back iron 123 and the fifth back iron 124 can be an integral structure with the third back iron 122, so that the relative positions of the various components in the first component 10 remain unchanged. The third through hole 312 in the magnetic levitation voice coil motor also penetrates the sixth back iron 125 and the fourth magnet 114, so that the relative positions of the first coil 221, the second coil 222, and the first back iron 211 can remain unchanged using connecting members.

[0086] Figure 15 It shows Figure 13 The force-displacement curve of the magnetic levitation voice coil motor is shown below. Figure 15 In the middle, curve 023 is Figure 13 The curves shown are of the Lorentz force versus displacement of the magnetic levitation voice coil motor, curve 024 being... Figure 7 The curves shown represent the Lorentz force versus displacement of the magnetic levitation voice coil motor. The Lorentz force at curve 023 is approximately twice that at curve 024, and curve 021 is... Figure 13 The curve shown represents the vertical resultant force and displacement of the magnetic levitation force and Lorentz force of the magnetic levitation voice coil motor. Curve 022 is... Figure 7 The curves showing the vertical resultant force and displacement of the magnetic levitation force and Lorentz force of the magnetic levitation voice coil motor are presented. Based on simulation calculations and... Figure 15 It can be seen that by setting the fourth magnet 114 and the second coil 222, as well as the third magnet 113 and the first coil 221 on both sides of the first back iron 211 along the z direction, the output thrust of the magnetic levitation voice coil motor can be effectively improved, thereby improving the working performance of the magnetic levitation voice coil motor.

[0087] Figure 16 It shows Figure 14 The force-displacement curve of the magnetic levitation voice coil motor is shown below. Figure 16 In the middle, curve 031 is Figure 14 In the magnetic levitation voice coil motor shown, the curve of the downward attraction force versus displacement of the first back iron 211 is shown in curve 032. Figure 14 In the magnetic levitation voice coil motor shown, the curve of the upward attraction force versus displacement of the first back iron 211 is shown in curve 033. Figure 14 The figure shows the curves of the resultant force and displacement along the z-direction of the upward and downward attraction forces acting on the first back iron 211 in the magnetic levitation voice coil motor. In the figure, when the first magnet 111 and the second magnet 112 are symmetrically distributed about the first back iron 211 along the z-direction, the current position of the first back iron 211 is the zero point position. Based on simulation calculations and... Figure 16 It can be seen that by fixing the fourth back iron 123 and the fifth back iron 124 to the third back iron 122 or forming an integral structure, and by setting the third magnet 113 and the first coil 211, as well as the fourth magnet 114 and the second coil 222 on both sides of the first back iron 211 along the z direction, the zero point position of the curve 033 can be made close to the zero point position of the first back iron 211, which helps to improve the positioning accuracy of the mover in the first component 10 and the second component 20.

[0088] Example 3

[0089] This embodiment provides a magnetic levitation voice coil motor, which also includes a first component 10 and a second component 20. The similarities with the first embodiment will not be repeated. The difference is that in the magnetic levitation voice coil motor of this embodiment, the third magnet 113 is sleeved on the outside of the first coil 221.

[0090] In this embodiment, refer to Figures 17 to 19 The first component 10 includes a first magnet 111, a second magnet 112, and a third magnet 113 arranged coaxially and spaced apart along the z-direction. The second component 20 includes a first back iron 211 and a first coil 221 arranged coaxially with the first component 10. The first back iron 211 is located between the first magnet 111 and the second magnet 112. The third magnet 113 is sleeved on the outside of the first coil 221. The magnetization direction of the first magnet 111 and the second magnet 112 is along the z-direction, and the magnetization direction of the third magnet 113 is its radial direction. Optionally, the magnetic levitation voice coil motor is also provided with a third through hole 312, which passes through the first magnet 111, the second magnet 112, and the third magnet 113. The first coil 221 is located inside the third through hole 312. Through the third through hole 312, it is convenient to use a connector to keep the relative position of the first coil 221 and the first back iron 211 unchanged, thereby facilitating the installation and use of the magnetic levitation voice coil motor. Furthermore, the third through hole 312 is coaxially arranged with the first component 10.

[0091] In an optional embodiment, refer to Figure 18 and Figure 19The first component 10 may also include the third back iron 122, the fourth back iron 123, and the fifth back iron 124 as described in Embodiment 1. The fourth back iron 123 and the fifth back iron 124 may be spaced apart from the third back iron 122, connected to the third back iron 122, or integrally formed with the third back iron 122.

[0092] Furthermore, referring to Figure 19 The first magnet 111, the second magnet 112, the third magnet 113, and the fourth back iron 123 and the fifth back iron 124 are all connected to the sidewall of the first through hole 1221. The first magnet 111, the second magnet 112, and the third magnet 113 can be fixedly connected to the third back iron 122, for example, by bonding or other suitable means. The fourth back iron 123 and the fifth back iron 124 can be fixedly connected to the third back iron 122 by bonding or other suitable means, or they can be an integral structure with the third back iron 122. By sleeved the third magnet 113 on the outside of the first coil 221, the output thrust of the magnetic levitation voice coil motor can be increased, and the structure can be made more compact, further improving the integration and working performance of the magnetic levitation voice coil motor.

[0093] Example 4

[0094] This embodiment provides a magnetic levitation voice coil motor, which also includes a first component 10 and a second component 20. The similarities to Embodiment 3 will not be repeated here. The difference lies in that, in this embodiment, the first component 10 further includes a fourth magnet 114, and the second component 20 further includes a second coil 222.

[0095] In this embodiment, refer to Figure 20 and Figure 21 The fourth magnet 114 is coaxially arranged with the first magnet 111 and is located on the side of the first magnet 111 away from the first back iron 211. The second coil 222 is coaxially arranged with the first assembly 10. The fourth magnet 114 is sleeved on the outside of the second coil 222, and the magnetization direction of the fourth magnet 114 is its radial direction. The relative positions of the second coil 222, the first coil 221, and the first back iron 211 remain unchanged. The relative positions of the first magnet 111, the second magnet 112, the third magnet 113, and the fourth magnet 114 remain unchanged. By setting the fourth magnet 114 and the second coil 222, the strength of the distributed magnetic field inside the magnetic levitation voice coil motor can be enhanced, the magnetic levitation force and Lorentz force of the magnetic levitation voice coil motor can be increased, and the output thrust can be increased. Furthermore, loads can be set on both sides of the magnetic levitation voice coil motor along the z-direction, which improves its ease of use.

[0096] In an optional embodiment, refer to Figure 20 and Figure 21 The fourth magnet 114 can be spaced apart from the third back iron 122, or it can be connected to the third back iron 122. Further, refer to... Figure 21 The first magnet 111, the second magnet 112, the third magnet 113, the fourth magnet 114, the fourth back iron 123, and the fifth back iron 124 are all connected to the side wall of the first through hole 1221 to connect with the third back iron 122.

[0097] Figure 22 It shows Figure 21 The force-displacement curve of the magnetic levitation voice coil motor structure is shown below. Figure 22 In the middle, curve 043 is Figure 21 The curves shown represent the Lorentz force versus displacement of the magnetic levitation voice coil motor; curve 044 is... Figure 19 The curves shown represent the Lorentz force versus displacement of the magnetic levitation voice coil motor. The Lorentz force on curve 043 is approximately twice that on curve 044, and curve 041 is... Figure 21 The curve shown represents the vertical resultant force and displacement of the magnetic levitation force and Lorentz force of the magnetic levitation voice coil motor. Curve 042 is... Figure 19 The curves shown represent the vertical resultant force and displacement of the magnetic levitation force and Lorentz force of the magnetic levitation voice coil motor.

[0098] It can be seen that, compared to Figure 19 The magnetic levitation voice coil motor with the structure shown in this embodiment effectively improves the output thrust of the magnetic levitation voice coil motor by respectively arranging a third magnet 113 and a first coil 221, and a fourth magnet 114 and a second coil 222 on both sides of the first back iron 211 along the z-direction; and, by comparison Figure 15 and Figure 22 It can be seen that the structure of the magnetic levitation voice coil motor in this embodiment is more compact and the motor output is greater. In addition, referring to the beneficial effects of the magnetic levitation voice coil motor in Embodiment 2 compared to Embodiment 1, the magnetic levitation voice coil motor in this embodiment, compared to the structure in Embodiment 3, can also improve the positioning accuracy of the mover in the first component 10 and the second component 20.

[0099] In an optional embodiment, refer to Figure 23 The fourth magnet 114 may include a number of tile-shaped magnet structures, which are distributed in a circular pattern and adjacent magnet structures are connected to each other to form a cylindrical fourth magnet 114.

[0100] Example 5

[0101] This embodiment provides a magnetic levitation voice coil motor, including a first component 10 and a second component 20. The similarities with any of the embodiments in embodiments one to five will not be repeated. The difference is that in the magnetic levitation voice coil motor of this embodiment, the first back iron 211 has a thickness gradient region 2111.

[0102] In this embodiment, refer to Figure 24 The thickness gradient region 2111 is located in the central region of the first back iron 211 and is coaxially arranged with the first back iron 211. The thickness of the thickness gradient region 2111 gradually increases from the inside to the outside along its radial direction. By setting the thickness gradient region 2111, the linear range between the vertical resultant force and displacement of the magnetic levitation voice coil motor can be increased, thereby improving the vertical stroke range of the motor and enabling the magnetic levitation voice coil motor to have constant stiffness characteristics over a larger vertical stroke range.

[0103] It should be noted that the thickness gradient region 2111 in the first back iron 211 of this embodiment can be applied to any of the magnetic levitation voice coil motors in the aforementioned embodiments, and is not limited to... Figure 24 The structure shown is limited.

[0104] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify, alter, or combine the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A magnetic levitation voice coil motor, characterized by, The magnetic levitation voice coil motor comprises a first assembly (10) and a second assembly (20) which are arranged in parallel, and the axial direction of the first assembly (10) is the z direction, and the first assembly (10) and the second assembly (20) can move relative to each other along the z direction. The first assembly (10) comprises a first magnet (111), a second magnet (112) and a third magnet (113) which are coaxial and arranged in parallel along the z direction, the second assembly (20) comprises a first back iron (211) and a first coil (221) which are coaxial with the first assembly (10), the first back iron (211) is located between the first magnet (111) and the second magnet (112), the first coil (221) is located on the side of the first back iron (211) away from the first magnet (111), and the magnetization directions of the first magnet (111) and the second magnet (112) are both the z direction.

2. The magnetic levitation voice coil motor of claim 1, wherein, The first assembly (10) further comprises a third back iron (122), the third back iron (122) is provided with a first through hole (1221) which penetrates the third back iron (122) along the z direction, and the first magnet (111), the first back iron (211), the second magnet (112) and the third magnet (113) are located in the first through hole (1221).

3. The magnetic levitation voice coil motor of claim 2, wherein, The first assembly (10) further comprises a fourth back iron (123), the fourth back iron (123) is located between the second magnet (112) and the third magnet (113) and is connected to the second magnet (112) and the third magnet (113) respectively.

4. The magnetic levitation voice coil motor of claim 3, wherein, The first assembly (10) further comprises a fifth back iron (124), the fifth back iron (124) is connected to the side of the first magnet (111) away from the first back iron (211).

5. The magnetic levitation voice coil motor of claim 4, wherein, The fourth back iron (123) and the fifth back iron (124) are arranged in parallel with the third back iron (122).

6. The magnetic levitation voice coil motor of claim 4, wherein, The fourth back iron (123) is arranged in parallel with the third back iron (122), and the fifth back iron (124) is connected to the side wall of the first through hole (1221).

7. The magnetic levitation voice coil motor of claim 4, wherein, The fourth back iron (123) and the fifth back iron (124) are both connected to the side wall of the first through hole (1221).

8. The magnetic levitation voice coil motor of claim 7, wherein, The magnetic levitation voice coil motor is provided with a second through hole (311) which is coaxial with the first assembly (10) and penetrates the first assembly (10) and the first back iron (211) along the z direction.

9. The magnetic levitation coil motor according to any one of claims 1 to 8, characterized by The first coil (221) is sleeved on the outside of the third magnet (113), and the magnetization direction of the third magnet (113) is the z direction.

10. The magnetic levitation voice coil motor of claim 9, wherein, The first assembly (10) further comprises a second back iron (121), the second back iron (121) is connected to the side of the third magnet (113) away from the second magnet (112).

11. The magnetic levitation voice coil motor of claim 9, wherein, The first assembly (10) further comprises a fourth magnet (114) coaxially arranged with the first magnet (111), the fourth magnet (114) being located on a side of the first magnet (111) away from the first back iron (211); The second assembly (20) further comprises a second coil (222) coaxially arranged with the first assembly (10), the second coil (222) being sleeved outside the fourth magnet (114), and the magnetization direction of the fourth magnet (114) being the z direction.

12. The magnetic levitation voice coil motor of claim 11, wherein, The first assembly (10) further comprises a sixth back iron (125) connected to a side of the fourth magnet (114) away from the first back iron (211).

13. The magnetic levitation coil motor according to any one of claims 1 to 7, characterized by The third magnet (113) is sleeved outside the first coil (221), and the magnetization direction of the third magnet (113) is the radial direction thereof; The magnetic levitation voice coil motor is provided with a third through hole (312) coaxially arranged with the first assembly (10), the third through hole (312) penetrating the first magnet (111), the second magnet (112) and the third magnet (113).

14. The magnetic levitation voice coil motor of claim 13, wherein, The first assembly (10) further comprises a fourth magnet (114) coaxially arranged with the first magnet (111), the fourth magnet (114) being located on a side of the first magnet (111) away from the first back iron (211); The second assembly (20) further comprises a second coil (222) coaxially arranged with the first assembly (10), the fourth magnet (114) being sleeved outside the second coil (222), and the magnetization direction of the fourth magnet (114) being the radial direction thereof.

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