A planar motor stator and a planar motor applying the same

Abstract

The present application relates to the technical field of planar motor, and particularly relates to a planar motor stator and a planar motor applying the same, the stator comprising a coil winding module, a circuit board and a magnetic field sensor, wherein the coil winding module comprises a first coil winding and a second coil winding, an insulation layer is arranged between the two, and coil units inside are arranged in an interlaced distribution manner; the planar motor comprises the above stator and a mover, a Halbach magnet array is arranged on the mover, the magnetic field sensor is integrated on the circuit board and is used for monitoring magnetic field changes in real time, and an auxiliary winding is connected to a current controller. Through improvement of the planar motor stator coil, uniformity of air gap magnetic field distribution is improved, thrust fluctuation and tooth slot torque are reduced, a main control unit generates excitation parameters according to magnetic field feedback signals and mover position information, closed loop control of the auxiliary winding is realized, and stability of system operation and positioning accuracy are improved.

Description

Technical Field

[0001] This invention belongs to the field of planar motor technology, and particularly relates to a planar motor stator and a planar motor using the stator. Background Technology

[0002] In the field of modern high-precision motion control, planar motors are widely used in high-end applications such as semiconductor manufacturing equipment, precision machining platforms, and automated assembly systems due to their advantages of eliminating the need for mechanical transmission, fast response speed, and high positioning accuracy. A planar motor typically consists of a fixed stator and a mover that can move freely within a plane relative to the stator. The mover achieves multi-degree-of-freedom motion under the influence of the magnetic field generated by the stator through electromagnetic induction, eliminating the need for traditional mechanical transmission mechanisms and thus avoiding problems affecting system accuracy such as backlash and frictional losses.

[0003] In existing technologies, the stator of a planar motor typically consists of one or more coil windings. By controlling the current in each phase winding, a spatially controllable driving magnetic field is generated, thereby achieving precise control of the mover's trajectory. However, for applications requiring high stability and precision machining, existing planar motor stators suffer from the following problems: Uneven magnetic field distribution leads to output fluctuations: Traditional stator coil windings, using a uniform turns distribution and fixed arrangement, are difficult to adapt to dynamic load changes, easily causing localized excessively high or insufficient air gap magnetic flux density, resulting in thrust fluctuations and increased cogging torque, affecting positioning accuracy. Furthermore, when the planar motor is operating at high speed, the magnetic field strength in the edge region of the coil array is often lower than in the central region due to the edge effect. The edge effect refers to the significant decrease in magnetic field strength at the edges of the coil array due to the lack of magnetic field superposition from adjacent coils, forming a so-called "weak magnetic field region." This phenomenon not only exacerbates the unevenness of the magnetic field distribution but may also cause unexpected behavior of the mover during movement, such as trajectory deviation or speed fluctuations, further reducing the overall system performance. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a planar motor stator, including a stator module. The stator module includes a coil winding module, a circuit board, and a magnetic field sensor. The coil winding module includes a first coil winding and a second coil winding. The first coil winding is located above the second coil winding. An insulating layer is provided between the first coil winding and the second coil winding. The coil units in the first coil winding and the second coil winding are staggered. After translation, the coil units of the first coil winding overlap with the coil units of the second coil winding in the vertical direction. The first coil winding includes multiple first coil units, and the second coil winding includes multiple second coil units. After translation along a first direction by L1 / 2, or along a second direction by L2 / 2, or along the first and second directions by L1 / 2 and L2 / 2 respectively, the first coil unit is aligned with the second coil unit in the vertical direction. L1 is the length of the first coil unit along the first direction, and L2 is the length of the first coil unit along the second direction.

[0005] Based on the above scheme, the coil winding module further includes a third coil winding and a fourth coil winding. The third coil winding is located above the fourth coil winding and below the second coil winding.

[0006] Preferably, the third coil winding includes a plurality of third coil units, and the fourth coil winding includes a plurality of fourth coil units, wherein the fourth coil units cover four third coil units.

[0007] Furthermore, the number of turns of the edge coil units of the first coil winding and the edge coil units of the second coil winding is greater than the number of turns of the intermediate coil unit.

[0008] Furthermore, a PCB auxiliary winding is provided between the stator modules, and a groove for fixing the PCB auxiliary winding is provided on the outer wall of the stator module housing. The auxiliary winding is connected to the circuit board through the groove opening.

[0009] Optionally, the stator module is provided with a detachable auxiliary winding module, which integrates an auxiliary winding. The stator module has a slot on its outer shell sidewall, and the detachable auxiliary winding is integrated into a plug block, which is placed in the slot.

[0010] Furthermore, the plug is inserted into the slot, and the plug is fixedly connected to the slot through a fixing structure.

[0011] Based on the above scheme, the fixing structure is an elastic locking tongue provided on both sides of the plug, and a slot adapted to the elastic locking tongue is opened on the inner wall of the slot at the position corresponding to the elastic locking tongue on both sides of the plug.

[0012] On the other hand, this application provides a planar motor, including the planar motor stator and mover described above. The mover includes a magnet array and a support member. The magnet array is a Heilbeck array, and the magnet array is fixedly installed in the mover by the support member.

[0013] Based on the above scheme, the magnetic field sensor is integrated on the circuit board for real-time monitoring of changes in magnetic field strength, and the auxiliary winding is connected to a current controller for adjusting the magnitude and direction of the current in the auxiliary winding.

[0014] Furthermore, the magnetic field sensor is an eddy current sensor or a Hall sensor.

[0015] Furthermore, the main control unit receives feedback signals from the magnetic field sensor in real time, and combines them with the spatial position information of the mover to generate excitation parameters for the coil winding module; the main control unit is connected to a current controller, which receives control signals sent by the main control unit; the current controller adjusts the current of the coil winding module according to the received control signals.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The coil winding layers of the coil winding module are arranged in an interleaved manner, which makes the magnetic field distribution more continuous, uniform and smooth, effectively reducing thrust fluctuation and cogging torque, thereby improving the stability and control accuracy of motor operation;

[0018] 2. An auxiliary winding is set between the stator modules, and the auxiliary winding module can be detached and installed through grooves or slots on the side wall of the housing. The auxiliary winding is connected to a current controller to adjust the local magnetic field distribution in real time according to control requirements, so as to achieve magnetic field compensation during the movement of the mover. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the cross-section of the planar motor stator of this application;

[0020] Figure 2 This is a schematic diagram of the winding layout according to an embodiment of this application;

[0021] Figure 3 This is a cross-sectional view of the stator structure of the multilayer coil of this application;

[0022] Figure 4 This is a schematic diagram of the winding layout in another embodiment;

[0023] Figure 5 This is a schematic diagram of the stator module structure;

[0024] Figure 6 This is another structural schematic diagram of the stator module. Detailed Implementation

[0025] The invention will be further described below with reference to specific embodiments. These specific embodiments are only used to explain the invention and are not intended to limit the scope of protection of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms indicating orientation or positional relationship used in this specification are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0026] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. Furthermore, technical features involved in the different embodiments of the invention described below may be combined with each other as long as they do not conflict with each other.

[0027] like Figure 1 As shown, this embodiment provides a planar motor stator, including a stator module. The stator module includes a coil winding module, a circuit board, and a magnetic field sensor 16. The coil winding module includes a first coil winding 11 and a second coil winding 12. The first coil winding is located above the second coil winding. The circuit board is placed between the first coil winding 11 and the second coil winding 12, and an insulating layer is provided between the circuit board and the first coil winding 11 and the second coil winding, respectively. The coil units within the first and second coil windings are spatially staggered, and this staggered arrangement aims to optimize the continuity and uniformity of the air gap magnetic field.

[0028] Example 1

[0029] This embodiment provides a planar motor stator, such as... Figure 2As shown, the first coil winding 11 includes a plurality of first coil units 111, and the second coil winding 12 includes a plurality of second coil units 121. The first coil unit is translated L1 / 2 along the first direction or L2 / 2 along the second direction to form the second coil unit. The edge of the first coil unit is aligned with the center of the second coil unit in the vertical direction.

[0030] According to the magnetic field distribution of existing coil windings, the magnetic field strength of each coil unit decreases from the center to the edge, and the magnetic field distribution between adjacent coil units is discontinuous. In this embodiment, the first coil unit and the second coil unit are staggered in the above-mentioned way, with the horizontal position staggered by half the length of the coil unit (L1 / 2 or L2 / 2), where L1 is the length of the first coil unit along the first direction and L2 is the length of the first coil unit along the second direction. The coil units are staggered in space so that the magnetic field of adjacent coils is continuously connected in the air gap, reducing magnetic field fluctuations.

[0031] In this embodiment, the weaker magnetic field at the edge of the first coil unit and the stronger magnetic field at the center of the second coil unit are superimposed in the vertical direction, which effectively fills the local magnetic flux deficiency caused by the attenuation of the edge magnetic field, making the magnetic field distribution in the entire air gap range smoother and more continuous, thereby improving the stability and control accuracy of the planar motor.

[0032] The first coil unit in this embodiment has the following specific structure: it includes four driving units, namely a first driving unit, a second driving unit, a third driving unit, and a fourth driving unit. The first driving unit is located in the upper left, the second driving unit in the upper right, the third driving unit in the lower left, and the fourth driving unit in the lower right. Each driving unit consists of a rectangular coil. The first and fourth driving units generate a horizontal thrust along the Y-axis, while the third and second driving units generate a horizontal thrust along the X-axis.

[0033] In this embodiment, the long side of the rectangular coil is four times the pole pitch, and the center distance between adjacent rectangular coils is 4 / 3 times the pole pitch. The coil arrangement suppresses the coupling between the driving force and driving torque generated by the short side, which facilitates decoupling calculation.

[0034] In other embodiments, those skilled in the art can, as needed, set the coil in the driving unit to a conventional shape such as a ring, hexagon, or rhombus.

[0035] Example 2

[0036] This embodiment provides a planar motor stator, which operates on the same principle as Embodiment 1. The first coil winding is translated L1 / 2 and L2 / 2 along the first and second directions respectively to form a second coil unit. The center of the first coil unit is aligned vertically with the center of the gap between the four second coil units, resulting in complementary superposition of the magnetic fields of the two winding layers. This is equivalent to moving either the first or second coil unit diagonally by 1 / 2 diagonal, so that they coincide vertically.

[0037] Similarly, aligning the center of the first coil unit with the gap center of the second coil unit allows the magnetic fields of the two windings to be phase-complementary in the air gap, further reducing thrust fluctuations and cogging torque, and improving the smoothness of motor operation.

[0038] Example 3

[0039] This embodiment provides a planar motor stator to address the issue that, within a limited stator area, the magnetic field distribution of coil units located at the edge of the winding array (edge ​​coil units) differs from that of coil units located inside the array (middle coil units) because there are no adjacent coils providing magnetic field supplementation. Therefore, based on embodiments 1-3 above, this embodiment further compensates for the edge windings by setting the number of turns of the edge coil units 101 of the first and second windings to be greater than the number of turns of the middle coil units 102. In traditional coil arrays, the magnetic field distribution of edge coil units is easily affected by edge effects due to the smaller number of adjacent coils, resulting in a lower magnetic flux density in the edge region compared to the central region. By increasing the number of turns of the edge coil units, the generated magnetomotive force can be enhanced, thereby forming a stronger magnetic field superposition in the edge region, offsetting the magnetic field attenuation caused by edge effects, and ensuring that the magnetic field strength in the edge region meets the control requirements.

[0040] In this embodiment, the edge coil unit is a coil unit located in 1-2 rows on the outer periphery of the first coil winding and the second coil winding, and the number of turns of the first row of edge coil units on the outer periphery is greater than the number of turns of the second row of edge coil units on the outer periphery.

[0041] This embodiment increases the magnetic field at the edge of the stator coil winding by increasing the number of turns in the edge coil unit, thereby offsetting the magnetic field attenuation caused by the edge effect.

[0042] Example 4

[0043] This embodiment provides a planar motor stator. Based on the above embodiment, the number of coil winding layers is further increased to provide higher degrees of freedom and smoothness in magnetic field control. Specifically, the coil winding module of this embodiment also includes a third coil winding and a fourth coil winding. The third coil winding is located above the fourth coil winding and below the second coil winding. Similarly, the coil units in the third and fourth coil windings are staggered.

[0044] like Figure 3 As shown, an insulating layer 13 is provided between the first coil winding 11 and the second coil winding, and an insulating layer is provided between the third coil winding 14 and the fourth coil winding 15. A circuit board is provided between the second coil winding and the third coil winding. A magnetic field sensor is integrated on the circuit board. A support column is provided between the circuit board and the second coil winding above the circuit board to prevent the components on the circuit board from being squeezed.

[0045] Optionally, the shape of the coil units in the first, second, third, and fourth coil windings can be set to ring, rectangle, rhombus, or regular hexagon, etc., and the coil windings can be set in the form of PCB layers.

[0046] Preferably, the insulating layer is an insulating material such as polyimide film or glass fiber reinforced epoxy resin. The insulating layer is directly embedded into the PCB layer during the manufacturing process to form an integrated structure. For example, in the manufacturing of multilayer PCBs, prepreg is used as an insulating medium to separate the copper foil layers.

[0047] Example 5

[0048] This embodiment also provides a planar motor stator. In this embodiment, the fourth coil unit in the fourth coil winding is larger than the third coil unit in the third coil winding, such as... Figure 4 As shown, the third coil winding includes multiple third coil units 141, and the fourth coil winding includes multiple fourth coil units 151. The center of the fourth coil unit is aligned vertically with the center of the coil gap where the four third coil units are joined, and the fourth coil unit covers four adjacent third coil units. Specifically, L3 is the length of the third coil unit along the first direction, L4 is the length of the third coil unit along the second direction, the length of the fourth coil unit along the first direction is 2L3, and the length of the fourth coil unit along the second direction is 2L4.

[0049] In traditional designs, splicing four third coil units creates a magnetic field "break" at the gap, causing fluctuations in magnetic flux density. By introducing a larger fourth coil unit to cover the gap area and aligning its center with the center of the gap, a seamless connection of the magnetic field at the gap can be achieved.

[0050] Example 6

[0051] This embodiment provides a planar motor stator. Based on the above embodiment, an auxiliary winding is provided to compensate for the uneven magnetic field at the edge of the main winding (coil winding) and to work in coordination with the main winding through electromagnetic induction.

[0052] Specifically, auxiliary windings are provided between the stator modules, such as... Figure 5 As shown, the stator module housing 2 has a groove 21 on its side wall for fixing the auxiliary winding. The auxiliary winding is connected to a circuit board or power supply through the groove opening 22. Preferably, the auxiliary winding can be configured as a PCB auxiliary winding. On the one hand, the auxiliary winding can compensate for magnetic field distortion (such as edge effect or harmonic interference) in the edge region of the main winding by adjusting the current, thereby improving the uniformity of the air gap magnetic field. On the other hand, the auxiliary winding can serve as an additional control loop, which can optimize the magnetic field of the main winding in real time by adjusting its current direction or amplitude, thereby improving the magnetic field uniformity and stability of the system.

[0053] The groove 21 provides embedded installation space for the auxiliary winding, avoiding damage or breakage of the winding due to mechanical stress. The sidewall of the groove 21 is coated with insulating material to ensure the insulation performance between the auxiliary winding and the stator module housing, preventing leakage or short circuit.

[0054] Example 7

[0055] This embodiment provides a planar motor stator, which has the same structure as embodiment 6. The difference is that if the auxiliary winding fails, the stator module needs to be disassembled for inspection and replacement, which will lead to problems such as low maintenance efficiency and prolonged downtime.

[0056] In this embodiment, the stator module is equipped with a detachable auxiliary winding module, which integrates auxiliary windings, such as... Figure 6 As shown, slots are provided on the side wall of the stator module housing 2, and the auxiliary winding module is integrated into a detachable plug-in block. The plug-in block is installed in the slot 23 of the stator module housing by plugging in and is fixed by a fixing structure to ensure structural stability and vibration resistance during operation. In addition, the plug-in block is provided with an electrical connection interface for signal and power transmission between the auxiliary winding and the control system.

[0057] According to this embodiment, the fixing structure is an elastic locking tongue provided on both sides of the plug block. A slot adapted to the elastic locking tongue is opened on the inner wall of the slot corresponding to the position of the elastic locking tongue on both sides of the plug block. The plug block is installed in the slot by plugging, and the locking tongue automatically engages with the slot to achieve fixation, ensuring structural stability and vibration resistance during operation.

[0058] In other embodiments, the fixing structure is a connection structure used in the prior art, such as a buckle or screw, and those skilled in the art can fix the plug block in the slot through reasonable structural design.

[0059] When the auxiliary winding fails, there is no need to disassemble the entire stator module. The inspection or replacement can be completed simply by removing the plug from the slot, which greatly shortens the maintenance time and improves the system availability. Furthermore, auxiliary winding modules with different functions or parameters can be quickly replaced through a unified slot.

[0060] In Embodiments 6 and 7 of this application, the auxiliary winding serves as an additional control loop. By adjusting its current direction or amplitude, it can achieve real-time optimization of the magnetic field of the main winding and improve the uniformity of the magnetic field.

[0061] On the other hand, this application provides a planar motor, including the aforementioned planar motor stator and mover. The stator module includes a coil winding module and an auxiliary winding module. The mover includes a permanent magnet array composed of a Halbach magnet array and a support for fixing the magnet array. When the mover moves above the stator, the stator windings are energized to generate a controllable electromagnetic field, which interacts with the permanent magnet array in the mover to generate the required propulsion and levitation force, achieving contactless drive and levitation. This planar motor utilizes the aforementioned stator module to ensure continuous connection of the magnetic field in space, reducing air gap flux fluctuations and improving thrust stability. Preferably, the magnet array is a double-layer Halbach array or an axially biased magnetic pole structure, forming an asymmetric magnetic field distribution, further optimizing the magnetic field distribution and improving the system's operational stability and response speed.

[0062] The planar motor also includes a magnetic field sensor, a current controller, and a main control unit. The magnetic field sensor is an eddy current sensor or a Hall sensor, which can monitor changes in magnetic field strength in real time and send the data to the main control unit. In addition to receiving feedback signals from the magnetic field sensor, the main control unit calculates the spatial position information of the mover based on these signals and obtains parameters such as the mover's trajectory and velocity. Based on the electromagnetic force required for the mover's motion, it calculates the excitation current needed for the coil winding module and the auxiliary winding module, generates control signals, and sends them to the current controller. The current controller connects the coil winding module and the auxiliary winding module. This current controller receives control signals from the main control unit and adjusts the current in the coil winding module and the auxiliary winding module.

[0063] During actual operation, when the magnetic field sensor detects that the edge magnetic field cannot meet the requirements of the mover's movement, the main control unit calculates the current value that needs to be compensated and sends it to the current controller. The current controller adjusts the current of the auxiliary winding to generate the corresponding compensating magnetic field, thereby realizing closed-loop control and meeting the needs of mover control.

[0064] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the article or device that includes said element.

[0065] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0066] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if these modifications and variations fall within the scope of the claims of this application and their equivalents, the intent of this application also includes these modifications and variations.

Claims

1. A planar motor stator comprising a stator module, the stator module comprising a coil winding module, a circuit board and a magnetic field sensor, the coil winding module comprising a first coil winding (11), a second coil winding (12), the first coil winding (11) being located above the second coil winding (12), characterized in that, The first coil winding (11) and the second coil winding (12) are provided with an insulation layer (13), the coil units in the first coil winding (11) and the second coil winding (12) are staggered, the first coil winding (11) comprises a plurality of first coil units (111), the second coil winding (12) comprises a plurality of second coil units (121), the first coil unit (111) is aligned with the second coil unit in the vertical direction after being translated by L1 / 2 in the first direction, or after being translated by L2 / 2 in the second direction, or after being translated by L1 / 2 and L2 / 2 in the first and second directions respectively, wherein L1 is the length of the first coil unit (111) in the first direction, and L2 is the length of the first coil unit (111) in the second direction. The stator module is provided with a detachable auxiliary winding module, and an auxiliary winding is integrated in the detachable auxiliary winding module.

2. A planar motor stator according to claim 1, characterised in that The coil winding module further comprises a third coil winding (14) and a fourth coil winding (15), the third coil winding (14) is located above the fourth coil winding (15), and the third coil winding (14) is located below the second coil winding (12).

3. A planar motor stator according to claim 2, characterised in that, The third coil winding (14) comprises a plurality of third coil units (141), the fourth coil winding (15) comprises a plurality of fourth coil units (151), and the fourth coil unit covers four third coil units.

4. A planar motor stator according to any one of claims 1-3, characterized in that The number of turns of the edge coil unit of the first coil winding (11) and the edge coil unit (101) of the second coil winding (12) is greater than that of the middle coil unit (102).

5. The planar motor stator of claim 3, wherein, PCB auxiliary windings are arranged between the stator modules, recesses (21) for fixing the PCB auxiliary windings are arranged on the side walls of the housings (2) of the stator modules, and the auxiliary windings are connected to the circuit boards through recess openings (22).

6. The planar motor stator of claim 1, wherein, The insertion block is fixedly connected with the insertion slot (23) through a fixing structure, and the fixing structure is an elastic lock tongue arranged on both sides of the insertion block.

7. A planar motor stator according to claim 6, characterised in that The fixing structure is an elastic lock tongue arranged on both sides of the insertion block, and a clamping groove matched with the elastic lock tongue is arranged on the inner wall of the insertion slot (23) corresponding to the positions of the elastic lock tongues on both sides of the insertion block.

8. A planar motor, characterized by The planar motor stator of claim 1 and a mover are included, the mover includes a magnet array and a support, the magnet array is a Halbach array, and the magnet array is fixedly installed in the mover through the support.

9. The planar motor of claim 8, wherein, The magnetic field sensor is integrated on the circuit board to monitor the change of the magnetic field strength in real time, the auxiliary winding is connected to a current controller, and the current controller is used to adjust the current size and direction of the auxiliary winding.

10. The planar motor of claim 9, wherein, The magnetic field sensor is an eddy current sensor or a Hall sensor.

11. The planar motor of claim 9, wherein, The main control unit receives feedback signals from the magnetic field sensor in real time, generates excitation parameters of the coil winding module; the main control unit is connected with a current controller, and the current controller receives control signals sent by the main control unit; the current controller adjusts the current of the coil winding module according to the received control signals.

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