Single-end center-excitation cylindrical electromagnetic actuator with combined guidance and driving

Abstract

The present invention relates to the field of vibration measurement technology, and in particular to a single-end central excitation cylindrical electromagnetic actuator with combined guidance and driving, comprising an electromagnetic driving component and a moving component; the electromagnetic driving component comprises a lower magnetic yoke in a cylindrical shape, an upper magnetic yoke in an annular shape arranged on the upper side of the lower magnetic yoke, a cylindrical permanent magnet arranged on the upper side of the lower magnetic yoke, and a cylindrical central magnetic yoke arranged on the upper side of the permanent magnet; the inner sides of the lower magnetic yoke and the upper magnetic yoke are surrounded by the permanent magnet and the central magnetic yoke to form a moving cavity; an air gap is arranged between the upper magnetic yoke and the central magnetic yoke; the moving component comprises a working table located on the upper side of the central magnetic yoke, a coil frame is arranged on one side of the working table close to the central magnetic yoke, and the coil frame is slidably sleeved on the outer side of the central magnetic yoke; the outer wall of the coil frame is wound with a DC coil and an excitation coil. By adopting the above scheme, the difficulty of assembling the moving component is reduced to the greatest extent, the dead weight of the moving component is reduced, and the assembly accuracy and driving ability of the electromagnetic actuator are effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of vibration measurement, and mainly relates to a single-end central excitation cylindrical electromagnetic actuator with combined guidance and driving. Background Art

[0002] Related research in the fields of aerospace, earthquake prevention and disaster reduction, precision micro-vibration isolation, etc. has increasingly higher requirements for the performance of electromagnetic actuators. Traditionally, electromagnetic actuators with separate drive and guide mechanisms are prone to introduce errors during assembly, causing serious distortion of the electromagnetic drive waveform and high lateral vibration ratio; separate drive and guide mechanisms require larger moving parts, and large size means large mass, which will seriously weaken its electromagnetic drive ability and is not conducive to the compactness of the equipment structure. Therefore, achieving high assembly precision and light mass of moving parts of electromagnetic actuators through effective design methods is the key to improving their performance.

[0003] Patent No. CN201510236281.5 discloses a symmetrically excited cylindrical low-frequency vibration calibration table with dual magnetic circuits at both ends for magnetic field tracking compensation. A cylindrical closed magnetic field structure design is proposed, in which two cylindrical permanent magnets are symmetrically installed at both ends of the central magnetic yoke and arranged with the same magnetic poles opposite to each other. The magnetic yoke forms two symmetrical closed magnetic circuits, and a highly uniform magnetic induction intensity distribution is generated in the air gap. The surface of the magnetic yoke adjacent to the air gap is provided with an array microstructure in the form of deep grooves, which can effectively suppress eddy current losses. A compensation coil is provided on the central magnetic yoke to form a compensation magnetic field to synchronously track and compensate for the influence of the armature reaction, and static pressure air floating guidance technology is used to ensure the motion guidance accuracy.

[0004] Patent No. CN201811332560.1 discloses a vibration table. It generates a magnetic field through a magnetic circuit device, and fixes an air bearing on the periphery of the dynamic coil frame to reduce lateral disturbances. The DC coil and the excitation coil are radially wound around the outer peripheral wall of the dynamic coil frame. The DC coil is located in the linear magnetic field area. The DC excitation is used to position the dynamic coil at a position where the DC Ampere force is equal to its gravity to offset the gravity and determine the zero position. The excitation coil is located in the uniform magnetic field area and is excited by AC to generate standard vibration.

[0005] In summary, the separation of the guide device and the drive structure increases the difficulty of axially parallel fixed installation of the electromagnetic drive structure and the guide device, which easily distorts the vibration waveform and produces lateral vibration; the separation of the guide and drive mechanisms hinders the miniaturization and light-weight design of moving parts, and seriously restricts the driving capacity of the electromagnetic actuator. For low-frequency electromagnetic vibration tables that often calibrate large vibration sensors, load capacity is even more important; and patent CN201811332560.1 places the DC coil in an approximately linear magnetic field area, and its nonlinearity will reduce the accuracy of the vibration waveform.

[0006] Therefore, a single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving is provided through the innovation of the structure and principle of the electromagnetic vibration calibration platform. Summary of the invention

[0007] 1. Technical issues to be solved

[0008] In view of the deficiencies in the prior art, the present invention provides a single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving, which reduces the difficulty of assembling moving parts, reduces the deadweight of moving parts, and effectively improves the assembly accuracy and driving capability of the electromagnetic actuator.

[0009] (II) Technical solution

[0010] To achieve the above-mentioned purpose, an embodiment of the present application provides a single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving, comprising an electromagnetic driving component and a moving component; the electromagnetic driving component comprises a lower magnetic yoke in a cylindrical shape, an upper magnetic yoke in a ring shape arranged on the upper side of the lower magnetic yoke, a cylindrical permanent magnet arranged on the upper side of the lower magnetic yoke, and a cylindrical central magnetic yoke arranged on the upper side of the permanent magnet; the inner sides of the lower magnetic yoke and the upper magnetic yoke are surrounded by the permanent magnet and the central magnetic yoke to form a moving cavity; the upper magnetic yoke and the An air gap is provided between the central magnetic yokes; the moving component comprises a work surface located on the upper side of the central magnetic yoke, a coil frame is provided on a side of the work surface close to the central magnetic yoke, the coil frame is annular and is slidably sleeved on the outer side of the central magnetic yoke; a DC coil and an excitation coil are wound around the outer wall of the coil frame, a fixed DC current is passed through the DC coil to generate an Ampere force opposite to the gravity direction of the moving component; a controllable driving current is passed through the excitation coil to generate an electromagnetic driving force.

[0011] Preferably, a static pressure air floating structure is provided on the coil frame, and the static pressure air floating structure controls the formation of a static pressure air film between the coil frame and the central magnetic yoke.

[0012] Preferably, the static pressure air flotation structure includes a cylindrical cavity-type air chamber opened in the coil frame, and an air outlet is opened on a side of the coil frame close to the center magnetic yoke, the air outlet is connected to the air chamber, and the air outlet is evenly distributed on the inner surface of the coil frame; an air inlet is opened on the outer surface of the coil frame away from the center magnetic yoke, the air inlet is connected to the air chamber, and the air inlet is connected to an air supply source.

[0013] Preferably, the lower magnetic yoke, the upper magnetic yoke, the permanent magnet and the central magnetic yoke are coaxially arranged.

[0014] Preferably, a yoke fixing hole is provided on the upper yoke; the lower side surface of the upper yoke is detachably connected to the lower yoke; a mounting frame for fixing the permanent magnet and the center yoke is provided in the motion cavity; the mounting frame is annular, and an annular mounting platform and a mounting hole are provided on the mounting frame; the lower end of the inner side wall of the mounting platform abuts the permanent magnet, the upper end of the inner side wall of the mounting platform abuts the center yoke, and the lower side of the mounting frame is detachably connected to the lower yoke; the mounting frame covers the permanent magnet.

[0015] Preferably, a sliding guide rail or a rolling guide rail is provided between the coil frame and the central magnetic yoke.

[0016] Preferably, the permanent magnet includes one permanent magnet or a plurality of permanent magnets bonded to each other.

[0017] Preferably, the DC coil and the excitation coil are located in the air gap and in a region where the magnetic field is uniformly distributed; the DC coil and the excitation coil can be connected to each other.

[0018] Preferably, the fixed-size direct current is calculated by the following formula: DC =mg / (BL); in the formula, I DC is the magnitude of the DC current passed through the DC coil, m is the total mass of the moving parts and related components fixed on the work surface, g is the acceleration of gravity, B is the average magnetic induction intensity distributed in the air gap, and L is the length of the DC coil.

[0019] (III) Beneficial effects

[0020] The present invention provides a single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving. By arranging a lower yoke, a permanent magnet, an upper yoke, a central yoke and a mounting frame, the lower yoke, the permanent magnet, the upper yoke and the central yoke can be quickly and coaxially installed. The design of the combination of a static pressure air floating structure and a central yoke effectively reduces the difficulty of assembling moving parts, reduces the dead weight of moving parts, and improves the assembly accuracy and driving ability of the electromagnetic actuator. In addition, the DC coil is located in an area with uniform magnetic field distribution, thereby avoiding the introduction of interference.

[0021] The specific beneficial effects are as follows:

[0022] (1) The magnetic circuit structure of the permanent magnet single-end center excitation adopted by the present invention can generate a more uniform magnetic induction intensity in the air gap, and the air gap edge effect has little influence, which is suitable for occasions with high motion accuracy requirements. Since the permanent magnet is inside the magnetic circuit structure, the leakage flux generated on the work surface is small, and the impact on the sensor installed on the table is small. The use of axially magnetized cylindrical permanent magnets is easy to manufacture and has low production costs.

[0023] (2) The present invention processes the central magnetic yoke into a guide shaft and the coil frame into a sliding mechanism, completing the design of a guide and drive composite electromagnetic actuator and achieving high assembly accuracy. The moving part is mounted on the guide shaft formed by the central magnetic yoke as a sliding mechanism, and the guide and drive are integrated through a static pressure air floating structure, a sliding guide rail or a rolling guide rail, which ensures that the moving part is parallel to the axial direction of the electromagnetic drive structure to the greatest extent, achieving high assembly accuracy and avoiding lateral vibration caused by assembly errors.

[0024] (3) The present invention realizes the miniaturization design of the electromagnetic actuator, which can improve its load capacity. The electromagnetic actuator with integrated guidance and drive has a compact structure and a smaller device volume, which is convenient for installation and transportation. The small size of the moving parts realizes the light weight of the moving parts, which effectively improves the load capacity of the electromagnetic actuator.

[0025] (4) The present invention can avoid the problem of the DC coil being subjected to nonlinear force in the approximately linear region of the air gap, thereby increasing the problem of vibration harmonic distortion. The DC coil is placed in the region where the air gap magnetic field is evenly distributed, and a fixed amount of DC current is passed through it so that it is subjected to an Ampere force equal to the gravity of the moving parts, thereby avoiding harmonic interference to the vibration caused by nonlinear electromagnetic force. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The schematic diagram of the structure of a single-ended centrally excited cylindrical electromagnetic actuator for combined guidance and driving;

[0027] Figure 2 A cross-sectional view of a single-ended centrally excited cylindrical electromagnetic actuator for combined guidance and driving;

[0028] Figure 3 A cross-sectional view of a protruding mounting frame in a single-ended centrally excited cylindrical electromagnetic actuator for combined guidance and driving;

[0029] Figure 4 A schematic diagram of a protruding mounting frame in a single-ended centrally excited cylindrical electromagnetic actuator for combined guidance and driving;

[0030] Figure 5 The schematic diagram of the magnetic pole distribution and magnetic circuit in a single-ended center-excited cylindrical electromagnetic actuator for combined guidance and driving;

[0031] Figure 6 A cross-sectional view of a protruding moving part in a single-ended centrally excited cylindrical electromagnetic actuator for combined guidance and driving;

[0032] Figure 7 Schematic diagram of the protruding static pressure air-floating structure in the single-end centrally excited cylindrical electromagnetic actuator for combined guidance and driving;

[0033] Figure 8Schematic diagram of the location of the protruding air inlet hole in a single-ended centrally excited cylindrical electromagnetic actuator that is a combination of guidance and drive.

[0034] Markings in the accompanying drawings:

[0035] 100, electromagnetic drive component; 110, lower magnetic yoke; 120, permanent magnet; 130, upper magnetic yoke; 130a, magnetic yoke mounting hole; 140, motion cavity; 150, center magnetic yoke; 160, air gap; 170, mounting frame; 170a, mounting platform; 170b, mounting hole;

[0036] 200, moving parts; 210, work surface; 220, coil frame; 230, DC coil; 240, excitation coil; 250, static pressure air floating structure; 251, air chamber; 252, air outlet; 253, air inlet. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example

[0039] The present invention provides a single-end central excitation cylindrical electromagnetic actuator with combined guidance and driving, see Figure 1-Figure 8 , including an electromagnetic driving component 100 and a moving component 200.

[0040] The electromagnetic drive component 100 includes a lower magnetic yoke 110 in a cylindrical shape, an upper magnetic yoke 130 in a ring shape disposed on the upper side of the lower magnetic yoke 110, a cylindrical permanent magnet 120 disposed on the upper side of the lower magnetic yoke 110, and a cylindrical central magnetic yoke 150 disposed on the upper side of the permanent magnet 120; the inner sides of the lower magnetic yoke 110 and the upper magnetic yoke 130 are surrounded by the permanent magnet 120 and the central magnetic yoke 150 to form a motion cavity 140; an air gap 160 is disposed between the upper magnetic yoke 130 and the central magnetic yoke 150. In this embodiment, the width of the air gap 160 is 10 mm, and a highly uniform magnetic induction intensity distribution is formed therein.

[0041] Furthermore, the lower magnetic yoke 110 , the upper magnetic yoke 130 , the permanent magnet 120 and the central magnetic yoke 150 are coaxially arranged.

[0042] The upper yoke 130 is provided with a yoke mounting hole 130a; the lower side of the upper yoke 130 is detachably connected to the lower yoke 110; during installation, the upper yoke 130 can be connected and fixed to the lower yoke 110 by means of bolts passing through the yoke mounting hole 130a.

[0043] A mounting frame 170 for fixing the permanent magnet 120 and the center magnetic yoke 150 is arranged in the motion cavity 140; the mounting frame 170 is annular, and an annular mounting platform 170a and a mounting hole 170b are provided on the mounting frame 170; during installation, the mounting frame 170 can be connected and fixed to the lower magnetic yoke 110 by passing a bolt through the mounting hole 170b. The lower end of the inner side wall of the mounting platform 170a abuts against the permanent magnet 120, and the upper end of the inner side wall of the mounting platform 170a abuts against the center magnetic yoke 150. The lower side of the mounting frame 170 can be detachably connected to the lower magnetic yoke 110; the mounting frame 170 covers the permanent magnet 120. The position of the permanent magnet 120 and the center magnetic yoke 150 can be fixed by setting the mounting frame 170.

[0044] It should be noted that, in this embodiment, the mounting frame 170 is made of non-magnetic conductive material, such as aluminum alloy.

[0045] The permanent magnet 120 includes one permanent magnet 120 or a plurality of permanent magnets 120 bonded to each other.

[0046] Specifically, the permanent magnet 120 can be made of a strong magnetic permanent magnet made of NdFeB, and the residual magnetic strength of the NdFeB material used is 1.17T, and the coercive force is 890kA / m. The lower yoke 110, the center yoke 150, and the upper yoke 130 are all made of high magnetic permeability electrical pure iron material DT4C, with a maximum relative magnetic permeability of 12000 and a saturation magnetic flux of 2.5T.

[0047] The path of the magnetic lines of force formed by the permanent magnet 120 excitation to form the main magnetic circuit is as follows: Figure 5 As shown, it starts from the N pole of the permanent magnet 120, passes through the lower yoke 110, the upper yoke 130, the air gap 160, the center yoke 150 in sequence, and then returns to the S pole of the permanent magnet 120 to form a closed magnetic circuit.

[0048] The material of the moving part 200 is ceramic, aluminum alloy or beryllium. Specifically, it includes a work surface 210 located on the upper side of the central magnetic yoke 150, and a coil frame 220 is arranged on the side of the work surface 210 close to the central magnetic yoke 150. The coil frame 220 is annular and slidably sleeved on the outer side of the central magnetic yoke 150; a DC coil 230 and an excitation coil 240 are wound around the outer wall of the coil frame 220, and a fixed DC current is passed through the DC coil 230 to generate an Ampere force opposite to the gravity direction of the moving part 200; and a controllable driving current is passed through the excitation coil 240 to generate an electromagnetic driving force.

[0049] The moving component 200 is made of aluminum alloy and is cylindrical in shape as a whole.

[0050] The DC coil 230 and the excitation coil 240 are formed by winding the insulated copper enameled wire on the outer surface of the coil frame 220, with an O-shaped cross section and a thickness of 3mm. The maximum current density is 5A / mm 2 After the magnetic circuit structure of the electromagnetic vibration table is assembled, the DC coil 230 , the excitation coil 240 and the coil frame 220 are located in the air gap 160 .

[0051] The fixed DC current is calculated by the following formula: DC =mg / (BL). In the formula, I DC is the magnitude of the DC current passed through the DC coil 230, m is the total mass of the moving part 200 and related components fixed on the work surface 210, g is the gravitational acceleration, B is the average magnetic induction intensity distributed in the air gap 160, and L is the length of the DC coil 230.

[0052] The DC coil 230 and the excitation coil 240 are located in the air gap 160 and in the area where the magnetic field is uniformly distributed; when the DC coil 230 does not need to offset the gravity of the moving part 200, the DC coil 230 and the excitation coil 240 can be connected to each other and a driving current can be passed to achieve a large electromagnetic driving force.

[0053] After the control signal is passed into the excitation coil 240 and amplified by the power amplifier, the effective value of the power current is up to tens of amperes. According to the electromagnetic field theory, the excitation coil 240 energized in the magnetic field is subjected to the vertical Ampere force, thereby outputting a precisely controllable electromagnetic driving force. The magnitude and direction of the electromagnetic driving force can be precisely controlled by controlling the magnitude and direction of the current passed. If the control signal adopts a standard sinusoidal electrical signal, the moving part 200 will generate a standard sinusoidal vibration along the axial direction under the action of the electromagnetic driving force.

[0054] In one embodiment, a static pressure air floating structure 250 is provided on the coil frame 220, and the static pressure air floating structure 250 controls the formation of a static pressure air film between the coil frame 220 and the central magnetic yoke 150. The static pressure air floating structure 250 is used to generate vertical standard vibration, and in this embodiment, the maximum stroke is 10mm.

[0055] The static pressure air floating structure 250 includes a cylindrical cavity air chamber 251 opened in the coil frame 220, and a side of the coil frame 220 close to the central magnetic yoke 150 is provided with an air outlet 252, the air outlet 252 is connected to the air chamber 251, and the air outlet 252 is evenly distributed on the inner surface of the coil frame 220. The outer surface of the coil frame 220 away from the central magnetic yoke 150 is provided with an air inlet 253, the air inlet 253 is connected to the air chamber 251, and the air inlet 253 is connected to the air supply source. Specifically, the diameter of the air hole can be 2mm.

[0056] In this embodiment, the lower cross-section of the coil frame 220 is annular and has a diameter of 80 mm. The static pressure air floating structure 250 is mounted on the central magnetic yoke 150 through the coil frame 220, so that the static pressure air floating guide rail and the axial direction of the electromagnetic drive structure are completely parallel, ensuring the assembly accuracy; during the assembly process, the inner surface of the coil frame 220 and the size of the central magnetic yoke 150 are matched, so that the coil frame 220 and the central magnetic yoke 150 can be easily assembled, and the assembly has high reliability.

[0057] In another embodiment, a sliding guide rail or a rolling guide rail may be further provided between the coil frame 220 and the central magnetic yoke 150 .

[0058] The present invention provides a single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving. By arranging a lower yoke 110, an upper yoke 130, a permanent magnet 120, a central yoke 150 and a mounting frame 170, the lower yoke 110, the upper yoke 130, the permanent magnet 120 and the central yoke 150 can be quickly and coaxially installed. At the same time, by arranging a static pressure air floating structure 250 and an integrated design of the central yoke 150, the difficulty of assembling the moving part 200 is reduced to the greatest extent, the dead weight of the moving part 200 is reduced, and the assembly accuracy and driving ability of the electromagnetic actuator can be effectively improved. In addition, the DC coil 230 is located in the area with uniform magnetic field distribution to avoid introducing interference.

[0059] The specific beneficial effects are as follows:

[0060] (1) The magnetic circuit structure of the single-end center excitation of the permanent magnet 120 adopted in the present invention can generate a more uniformly distributed magnetic induction intensity in the air gap 160, and the edge effect of the air gap 160 is small, which is suitable for occasions with high requirements for motion accuracy. Since the permanent magnet 120 is inside the magnetic circuit structure, the leakage flux generated on the worktable 210 is small, and the impact on the sensor installed on the table is small. The use of an axially magnetized cylindrical permanent magnet 120 is easy to manufacture and has a low production cost.

[0061] (2) The present invention processes the central magnetic yoke 150 into a guide shaft and the coil frame 220 into a sliding mechanism, thereby completing the design of a guide and drive composite electromagnetic actuator and achieving high assembly accuracy. The moving component 200 is mounted on the guide shaft formed by the central magnetic yoke 150 as a sliding mechanism, and the guide and drive are integrated through the static pressure air floating structure 250, the sliding guide rail form or the rolling guide rail form, which ensures that the moving component 200 is parallel to the axial direction of the electromagnetic drive structure to the greatest extent, achieving high assembly accuracy and avoiding lateral vibration caused by assembly errors.

[0062] (3) The present invention realizes the miniaturization design of the electromagnetic actuator, which can improve its load capacity. The electromagnetic actuator with integrated guidance and drive has a compact structure and a smaller device volume, which is convenient for installation and transportation. The small size of the moving part 200 realizes the light weight of the moving part 200, which effectively improves the load capacity of the electromagnetic actuator.

[0063] (4) The present invention can avoid the problem of the DC coil 230 being subjected to nonlinear force in the approximately linear region of the air gap 160, thereby increasing the problem of vibration harmonic distortion. The DC coil 230 is placed in the uniform magnetic field distribution region of the air gap 160, and a fixed amount of DC current is passed through it so that it is subjected to an Ampere force equal to the gravity of the moving part 200, thereby avoiding harmonic interference caused by nonlinear electromagnetic force to the vibration.

[0064] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "back" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, or an indirect connection through an intermediate medium, or the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0066] The above-mentioned embodiments only express the implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving, Features: It comprises an electromagnetic driving component (100) and a moving component (200); The electromagnetic drive component (100) comprises a lower magnetic yoke (110) in a cylindrical shape, an upper magnetic yoke (130) in a ring shape arranged on the upper side of the lower magnetic yoke (110), a cylindrical permanent magnet (120) arranged on the upper side of the lower magnetic yoke (110), and a cylindrical central magnetic yoke (150) arranged on the upper side of the permanent magnet (120); the inner sides of the lower magnetic yoke (110) and the upper magnetic yoke (130) are surrounded by the permanent magnet (120) and the central magnetic yoke (150) to form a motion cavity (140); an air gap (160) is arranged between the upper magnetic yoke (130) and the central magnetic yoke (150); The moving component (200) comprises a work surface (210) located on the upper side of the central magnetic yoke (150); a coil frame (220) is arranged on a side of the work surface (210) close to the central magnetic yoke (150); the coil frame (220) is annular and is slidably sleeved on the outer side of the central magnetic yoke (150); a DC coil (230) and an excitation coil (240) are wound around the outer wall of the coil frame (220); a fixed DC current is passed through the DC coil (230) to generate an Ampere force opposite to the gravity direction of the moving component (200); a controllable driving current is passed through the excitation coil (240) to generate an electromagnetic driving force; A static pressure air floating structure (250) is provided on the coil frame (220), and the static pressure air floating structure (250) controls the formation of a static pressure air film between the coil frame (220) and the central magnetic yoke (150); The static pressure air floating structure (250) comprises a cylindrical cavity-type air chamber (251) opened in the coil frame (220), and a side surface of the coil frame (220) close to the central magnetic yoke (150) is provided with an air outlet hole (252), the air outlet hole (252) is connected to the air chamber (251), and the air outlet holes (252) are evenly distributed on the inner surface of the coil frame (220); An air inlet hole (253) is provided on the outer surface of the coil frame (220) away from the central magnetic yoke (150), and the air inlet hole (253) is connected to the air chamber (251), and the air inlet hole (253) is connected to an air supply source.

2. The single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving according to claim 1, Features: The lower magnetic yoke (110), the upper magnetic yoke (130), the permanent magnet (120) and the central magnetic yoke (150) are coaxially arranged.

3. A single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving according to claim 1, Features: The upper magnetic yoke (130) is provided with a magnetic yoke fixing hole (130a); the lower side surface of the upper magnetic yoke (130) is detachably connected to the lower magnetic yoke (110); The moving cavity (140) is provided with a mounting frame (170) for fixing the permanent magnet (120) and the central magnetic yoke (150); the mounting frame (170) is annular, and an annular mounting platform (170a) and a mounting hole (170b) are provided on the mounting frame (170); the lower end of the inner side wall of the mounting platform (170a) abuts against the permanent magnet (120), and the upper end of the inner side wall of the mounting platform (170a) abuts against the central magnetic yoke (150), and the lower side of the mounting frame (170) is detachably connected to the lower magnetic yoke (110); the mounting frame (170) covers the permanent magnet (120).

4. The single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving according to claim 1, Features: A sliding guide rail or a rolling guide rail is provided between the coil frame (220) and the central magnetic yoke (150).

5. A single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving according to claim 1, Features: The permanent magnet (120) includes one permanent magnet (120) or a plurality of permanent magnets (120) bonded to each other.

6. The single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving according to claim 1, Features: The DC coil (230) and the excitation coil (240) are located in the air gap (160) and in a region where the magnetic field is evenly distributed; the DC coil (230) and the excitation coil (240) are connected to each other or not connected.

7. The single-ended centrally excited cylindrical electromagnetic actuator with combined guidance and driving according to claim 1, Features: The fixed DC current is calculated by the following formula: DC =mg / (BL); in the formula, I DC is the magnitude of the direct current passed through the DC coil (230), m is the total mass of the moving part (200) and related components fixed on the work surface (210), g is the acceleration of gravity, B is the average magnetic induction intensity distributed in the air gap (160), and L is the length of the DC coil (230).

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