An assembly fixture and method for a two-dimensional halbach permanent magnet array

Abstract

The application discloses an assembling tool for a two-dimensional Halbach permanent magnet array, and provides an assembling method. The tool can effectively overcome the interference of strong interaction force between magnets, and ensure high compactness and high flatness of the magnet arrangement.

Description

Technical Field

[0001] This invention belongs to the field of magnet technology, and particularly relates to an assembly tooling and method for a two-dimensional Halbach permanent magnet array. Background Technology

[0002] A two-dimensional Halbach array is a magnetic structure composed of permanent magnets with different magnetization directions arranged in a specific spatial sequence. Its core principle is to significantly enhance the magnetic field on one side of the array and significantly weaken it on the other through the ingenious arrangement of magnetization vectors. This unique magnetic field distribution characteristic makes it valuable in fields requiring strong and high-gradient magnetic fields, such as magnetic levitation and high-precision magnetic levitation platforms. Building upon one-dimensional arrays, the two-dimensional Halbach array, through the combination of multi-directional magnets within a plane, can achieve more complex, uniform, or enhanced magnetic field distributions within a two-dimensional plane, which is crucial for improving the performance of related equipment.

[0003] In applications such as high-precision maglev motion platforms, the levitation and actuation of the mover (typically a component carrying energized coils) depend on the magnetic field generated by the stator. Using a two-dimensional Halbach array as the stator provides a strong and uniform magnetic field for the mover, which is crucial for achieving multi-degree-of-freedom, high-precision, and high-dynamic-response motion. The assembly quality of this array, especially the size of the gaps between magnet units, the overall flatness of the array, and the accuracy of the magnetization direction alignment, directly determines the strength and uniformity of the working air gap magnetic field, thus affecting the thrust density, positioning accuracy, motion stability, and load-bearing capacity of the maglev motion platform.

[0004] Currently, the assembly of two-dimensional Halbach arrays faces two main challenges. First, due to the strong attractive or repulsive forces between adjacent magnets in the array, these forces make it difficult to position and fix the magnets during assembly, especially when precise placement is required. For example, under the interaction of the vertical magnetization component with the base magnetic field, some magnets experience upward repulsive forces and "levitate," making stable placement extremely difficult and posing significant challenges to precise positioning. Second, traditional assembly methods often employ modular bonding: a few magnets are pre-assembled into a module using adhesive, and then these modules are bonded to other magnets or modules to form a complete two-dimensional array. While this method avoids directly addressing the complex forces between all magnets to some extent, it also has significant drawbacks: 1) The process of magnetizing before assembly only alleviates the positioning problem by using the pressure bar to attract the main magnet that is subjected to upward force. The method of the pressure bar attracting the main magnet can only solve the "levitation" problem and cannot counteract the lateral magnetic interference (such as the lateral thrust of adjacent main magnets). This may cause a slight shift in the arrangement of magnets, which will ultimately affect the uniformity of the magnetic pole distance and the consistency of the magnetic field distribution of the array.

[0005] 2) The auxiliary magnetic poles of the next row are aligned with the end face of the auxiliary magnetic poles of the previous row as a reference. If the first row of auxiliary magnetic poles is slightly offset, the auxiliary magnetic poles of all subsequent rows will be offset as well, forming a "serial cumulative error", which will eventually lead to uneven magnetic pole pitch and disordered magnetic field distribution in the entire array. 3) The assembly process is cumbersome, resulting in poor efficiency and consistency in mass production.

[0006] Patent document CN121308453A discloses a single-magnet magnet ring assembly process for a robot joint motor rotor, comprising the following steps: S1: providing a motor rotor base and placing the motor rotor base on a support fixture; S2: using a magnetizer to magnetize multiple magnetic bodies one by one into permanent magnets, wherein at least two permanent magnets have different magnetic pole directions; S3: applying adhesive to the surface of the motor rotor base and / or the surface of the permanent magnets to be bonded; S4: transferring the motor rotor base on the support fixture to a magnetizing mechanism; S5: using the magnetizing mechanism to install multiple permanent magnets onto the motor rotor base supported by the support fixture to form a magnet ring, and fixing the magnet ring to the motor rotor base. The magnet ring is composed of multiple magnet assemblies connected end to end, each magnet assembly having multiple permanent magnets. The multiple permanent magnets in the same magnet assembly are a Heilbeck array, which improves the magnetic field strength and uniformity of the rotor.

[0007] Patent document CN121394098A discloses an adjustable magnetic field permanent magnet device for accelerators. This invention utilizes a base plate with a first inner ring bearing seat, a second inner ring bearing, a first outer ring bearing seat, and a second outer ring bearing seat to support precisely concentric, relatively rotatable inner and outer ring fixed cylinders. On the inner and outer ring fixed cylinders, respectively, are mounted inner and outer ring permanent magnet blocks that are circumferentially evenly distributed, axially arranged, and capable of radial adjustment. The inner and outer ring fixed cylinders are rotated by an inner ring motor device and an outer ring motor device, respectively. By changing the relative angle between the inner and outer ring permanent magnet blocks in the circumferential direction, the magnetic field can be adjusted. Summary of the Invention

[0008] The purpose of this invention is to provide an assembly fixture and method for a two-dimensional Halbach permanent magnet array. This assembly fixture can effectively overcome the interference of strong interaction forces between magnets, while ensuring that the magnet arrangement has high compactness and high flatness.

[0009] To achieve the first objective of this invention, the following technical solution is provided: an assembly fixture for a two-dimensional Halbach permanent magnet array, the two-dimensional Halbach permanent magnet array including a mounting base, and main magnetic blocks and side magnets arranged in an array on the mounting base. The main magnetic blocks and the adjacent main magnetic blocks are provided with mounting grooves for mounting the side magnets. The mounting grooves are intersected by mounting holes. The assembly fixture includes a longitudinal mounting base for the side magnets that spans two adjacent main magnetic blocks, a side magnet positioning block on the longitudinal mounting base for stacking the side magnets, and a clamp for gripping and placing the side magnets. The longitudinal mounting base of the side magnet has a vertically penetrating mounting opening on one side corresponding to the lower main magnetic block. The mounting opening is aligned with the mounting groove on one side of the lower main magnetic block. A limiting rod corresponding to the mounting hole is provided on one side of the lower adjacent main magnetic block below the longitudinal mounting base of the side magnet. The side magnet positioning block includes a mounting block and a limiting channel extending downward from the center of the mounting opening, wherein the outer wall of the limiting channel slides in contact with the inner wall of the mounting opening below. The clamp includes a clamp head and a push rod, and the clamp head has clamp arms on both sides for clamping the side magnets.

[0010] Specifically, the mounting port has two types, including a first mounting port whose opening length direction is consistent with the length direction of the longitudinal mounting base of the side magnet, and a second mounting port whose opening length direction is consistent with the width direction of the longitudinal mounting base of the side magnet.

[0011] Specifically, there are two first mounting ports, which are arranged in parallel to correspond to the mounting slots on both sides of the main magnetic block below.

[0012] Specifically, the longitudinal mounting base of the side magnet is provided with a first limiting hole on the surface surrounding the mounting opening, and the mounting block is provided with a second limiting hole corresponding to the first limiting hole at a position avoiding the limiting channel. During assembly, positioning bolts are used to fix the block through the second limiting hole and the first limiting hole.

[0013] Specifically, the upper surface of the mounting block has positioning grooves at both ends that correspond to the two clamping arms of the clamp.

[0014] Specifically, the clamping arm is provided with a third limiting hole for the set screw to laterally press against the end face of the side magnet.

[0015] Specifically, the clamp is provided with an iron block for adsorbing and positioning the side magnet, and an installation channel through the clamp and the iron block. The installation channel is used for the push rod to pass through to separate the side magnet in the adsorbed state.

[0016] To achieve the second objective of this invention, the following technical solution is provided: an assembly method, implemented using the aforementioned assembly fixture for a two-dimensional Halbach permanent magnet array, comprising: After selecting the target main magnetic block, install the limiting rod of the longitudinal mounting base of the side magnet in accordance with the mounting holes around the main magnetic block adjacent to the target main magnetic block; Align the limiting channel of the side magnet positioning block with the mounting port on the longitudinal mounting base of the side magnet to complete the nesting fixation, and use the positioning bolts to fix it a second time through the second limiting hole and the first limiting hole; After covering the surface of the side magnet with an epoxy board, the side magnet is attracted and positioned by the iron block on the chuck. At the same time, the two ends of the side magnet are clamped by the clamping arms on both sides of the chuck and the end face of the side magnet is tightened laterally by the set screw. After being gripped and fixed, the side magnet is transferred to the top of the side magnet positioning block, and the clamping arm is used to position it in conjunction with the positioning grooves on both sides of the mounting block. After unscrewing the set screw, the side magnet is separated from the iron block by the push rod, so that the side magnet passes through the limit channel and the mounting port in sequence and enters the mounting groove.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: Specialized assembly fixtures ensure direct metal-to-metal contact between the main magnet and the side magnets without adhesive each time, significantly improving the density of the magnet array, avoiding magnetic field inhomogeneity caused by inconsistent adhesive layer thickness, and fundamentally eliminating the adverse effects of adhesive shrinkage or stress deformation on array flatness. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the two-dimensional Halbach permanent magnet array provided in this embodiment; Figure 2 This is a schematic diagram of the longitudinal mounting base of the side magnet with a first mounting port provided in this embodiment. Figure 3 This is a schematic diagram of the longitudinal mounting base for the side magnet with a second mounting port provided in this embodiment. Figure 4 This is a schematic diagram of the side magnet positioning block provided in this embodiment; Figure 5 This is a schematic diagram of the chuck structure provided in this embodiment; Figure 6 This is a schematic diagram illustrating the use of assembly tooling in this embodiment; In the diagram, 1. Mounting base; 2. Enclosure; 3. Mounting hole; 4. Back iron; 5. Main magnet; 6. Side magnet; 7. Longitudinal mounting base for side magnet; 8. First mounting port; 9. First limiting hole; 10. Limiting rod; 11. Second mounting port; 12. Set screw; 13. Iron block; 14. Mounting channel; 15. Mounting block; 16. Second limiting hole; 17. Limiting channel; 18. Positioning groove. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] like Figure 1 As shown, the two-dimensional Halbach permanent magnet array provided in this embodiment includes a mounting base 1, and main magnets 5 and side magnets 6 arranged in an array on the mounting base 1. The mounting base 1 encloses multiple main magnets 5 and multiple side magnets 6 in the middle by a back iron 4 and a enclosure 2 to prevent subsequent fixation gel from overflowing.

[0021] The main magnetic block 5 and the adjacent main magnetic blocks 5 are all provided with mounting grooves for mounting the side magnets 6, and mounting holes 3 are provided at the intersection of multiple mounting grooves.

[0022] For the aforementioned two-dimensional Halbach permanent magnet array, this embodiment provides an assembly fixture for assembling the side magnet 6 and the main magnet 5 together. In this embodiment, the following is provided: Figure 2 and Figure 3 As shown, this embodiment provides two types of longitudinal mounting bases 7 for side magnets, which can be adapted to assembly tasks at different angles. Each type of longitudinal mounting base 7 for side magnets spans two adjacent main magnets 5. The longitudinal mounting base 7 for side magnets is provided with a first mounting port 8 and a second mounting port 11 that are vertically connected. The longitudinal mounting base 7 for side magnets is provided with a limiting rod 10 corresponding to the mounting hole 3 on one side of the adjacent main magnet 5 below it.

[0023] The first mounting port 8 is arranged along the length of the longitudinal mounting base 7 of the side magnet, and there are two of them arranged in parallel, thereby improving assembly efficiency.

[0024] The second mounting port 11 is arranged along the width direction of the longitudinal mounting base 7 of the side magnet, and there is only one.

[0025] like Figure 4 As shown, the side magnet positioning block provided in this embodiment is stacked on the side magnet longitudinal mounting base 7. The side magnet positioning block includes a mounting block 15 and a limiting channel 17. The outer wall of the limiting channel 17 slides in contact with the inner wall of the mounting opening below.

[0026] like Figure 5 As shown, the clamp includes a chuck and a push rod, and the chuck has clamping arms on both sides for holding the side magnets.

[0027] To facilitate better combination and use among multiple tooling components, the longitudinal mounting base of the side magnet is provided with a first limiting hole 9 around the mounting opening. The mounting block 15 is provided with a second limiting hole 16 corresponding to the first limiting hole 9, avoiding the limiting channel 17. During assembly, positioning bolts are used to fix the components through the second limiting hole 16 and the first limiting hole 9, thereby facilitating assembly and positioning by the user.

[0028] The upper surface of the mounting block 15 has positioning grooves 18 at both ends that correspond to the two clamping arms of the clamp, which can both speed up the alignment and prevent mistakes.

[0029] The aforementioned clamping arm is provided with a third limiting hole for tightening the set screw 12 to the end face of the side magnet 6 from the lateral side. There are multiple third limiting holes, which are arranged at intervals along the length direction of the clamping arm.

[0030] The chuck is equipped with an iron block 13 for adsorbing and positioning the side magnet, and an installation channel 14 that runs through the chuck and the iron block 13. The installation channel 14 is used for the push rod to pass through to separate the side magnet 6 in the adsorbed state. This method simplifies the steps of the chuck picking up or placing the side magnet 6.

[0031] This embodiment also provides an assembly method, implemented using the assembly fixture described above for a two-dimensional Halbach permanent magnet array, including: After selecting the target main magnetic block, install the limiting rod of the longitudinal mounting base of the side magnet in accordance with the mounting holes around the main magnetic block adjacent to the target main magnetic block; Align the limiting channel of the side magnet positioning block with the mounting port on the longitudinal mounting base of the side magnet to complete the nesting fixation, and use the positioning bolts to fix it a second time through the second limiting hole and the first limiting hole; After covering the surface of the side magnet with an epoxy board, the side magnet is attracted and positioned by the iron block on the chuck. At the same time, the two ends of the side magnet are clamped by the clamping arms on both sides of the chuck and the end face of the side magnet is tightened laterally by the set screw. After being gripped and fixed, the side magnet is transferred to the top of the side magnet positioning block, and the clamping arm is used to position it in conjunction with the positioning grooves on both sides of the mounting block. After loosening the set screw, the side magnet is separated from the iron block by the push rod, allowing the side magnet to pass through the limit channel and the mounting opening in sequence before entering the mounting groove. Figure 6 The diagram shows the assembly fixtures deployed on the mounting base.

[0032] Furthermore, the assembly process for the main magnetic block is as follows: All the surrounding barriers, pull-out screw fixtures, and side magnet replacement blocks were installed on the back iron in one go. Using a high-precision milling machine, the installation space for the main magnet, auxiliary magnet and grounding block is machined in one go, and the upper surface of all the installation fixtures is also machined. Apply adhesive evenly to the bottom of the main magnet. Use the surrounding perimeter and side magnets to replace the pre-drilled threaded holes on the block. Secure each magnet with a pressure plate after installation. The bonding of the main magnets is complete once the adhesive has fully cured.

[0033] Next is the assembly process for the auxiliary magnets: After all the main magnets have been bonded and magnetized, remove the auxiliary magnet replacement blocks. Use the side magnet installation tool to install the horizontal and vertical side magnets one by one.

[0034] In summary, the solution provided in this embodiment ensures direct metal-to-metal contact between the main magnet and the side magnets without adhesive. This not only significantly improves the density of the magnet array and avoids magnetic field inhomogeneity caused by inconsistent adhesive layer thickness, but also fundamentally eliminates the adverse effects of adhesive shrinkage or stress deformation on array flatness. This invention systematically solves the inherent assembly difficulties, low efficiency, and precision loss problems of traditional processes using assembly tooling. It achieves significant improvements in key indicators such as assembly efficiency, density, positional accuracy, and the magnetic field linearity and mechanical flatness of the final magnet array, providing a reliable manufacturing guarantee for high-performance magnetic levitation platforms.

[0035] Furthermore, the terms "upper," "lower," "inner," "outer," "front," and "rear" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Unless otherwise specifically stated, the relative steps, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0036] Of course, the above description is only a specific embodiment of the present invention and is not intended to limit the scope of the present invention. All equivalent changes or modifications made to the structure, features and principles described in the claims of the present invention should be included in the scope of the claims of the present invention.

[0037] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An assembly fixture for a two-dimensional Halbach permanent magnet array, the two-dimensional Halbach permanent magnet array comprising a mounting base, and main magnetic blocks and side magnets arranged in an array on the mounting base, wherein mounting grooves for mounting side magnets are provided between each main magnetic block and adjacent main magnetic blocks, and mounting holes are provided at the intersection of multiple mounting grooves, characterized in that, The assembly fixture includes a longitudinal mounting base for the side magnets that spans across two adjacent main magnets, a positioning block for the side magnets on the longitudinal mounting base for stacking the side magnets, and a clamp for gripping and placing the side magnets. The longitudinal mounting base of the side magnet has a through mounting opening on one side corresponding to the main magnetic block below. The mounting opening is aligned with the mounting groove on one side of the main magnetic block below. A limiting rod corresponding to the mounting hole is provided on one side of the longitudinal mounting base of the side magnet and the adjacent main magnetic block below. The side magnet positioning block includes a mounting block and a limiting channel extending downward from the center of the mounting opening, wherein the outer wall of the limiting channel slides in contact with the inner wall of the mounting opening below. The clamp includes a clamp head and a push rod, and the clamp head has clamp arms on both sides for clamping the side magnets.

2. The assembly fixture for a two-dimensional Halbach permanent magnet array according to claim 1, characterized in that, There are two types of mounting ports, including a first mounting port whose opening length direction is consistent with the length direction of the longitudinal mounting base of the side magnet, and a second mounting port whose opening length direction is consistent with the width direction of the longitudinal mounting base of the side magnet.

3. The assembly fixture for a two-dimensional Halbach permanent magnet array according to claim 2, characterized in that, There are two first mounting ports, which are arranged in parallel to correspond to the mounting slots on both sides of the main magnetic block below.

4. The assembly fixture for a two-dimensional Halbach permanent magnet array according to claim 1, characterized in that, The longitudinal mounting base of the side magnet has a first limiting hole on the surface surrounding the mounting opening. The mounting block has a second limiting hole arranged corresponding to the first limiting hole at a position that avoids the limiting channel. During assembly, positioning bolts are used to fix the block through the second limiting hole and the first limiting hole.

5. The assembly fixture for a two-dimensional Halbach permanent magnet array according to claim 1, characterized in that, The upper surface of the mounting block has positioning grooves at both ends that correspond to the two clamping arms of the clamp.

6. The assembly fixture for a two-dimensional Halbach permanent magnet array according to claim 1, characterized in that, The clamping arm is provided with a third limiting hole for the set screw to laterally press against the end face of the side magnet.

7. The assembly fixture for a two-dimensional Halbach permanent magnet array according to claim 1, characterized in that, The clamp is provided with an iron block for adsorbing and positioning the side magnet, and an installation channel through the clamp and the iron block. The installation channel is used for the push rod to pass through to separate the side magnet in the adsorbed state.

8. An assembly method, characterized in that, This is achieved using the assembly fixture for a two-dimensional Halbach permanent magnet array as described in any one of claims 1 to 7, comprising: After selecting the target main magnetic block, install the limiting rod of the longitudinal mounting base of the side magnet in accordance with the mounting holes around the main magnetic block adjacent to the target main magnetic block; Align the limiting channel of the side magnet positioning block with the mounting port on the longitudinal mounting base of the side magnet to complete the nesting fixation, and use the positioning bolts to fix it a second time through the second limiting hole and the first limiting hole; After covering the surface of the side magnet with an epoxy board, the side magnet is attracted and positioned by the iron block on the chuck. At the same time, the two ends of the side magnet are clamped by the clamping arms on both sides of the chuck and the end face of the side magnet is tightened laterally by the set screw. After being gripped and fixed, the side magnet is transferred to the top of the side magnet positioning block, and the clamping arm is used to position it in conjunction with the positioning grooves on both sides of the mounting block. After unscrewing the set screw, the side magnet is separated from the iron block by the push rod, so that the side magnet passes through the limit channel and the mounting port in sequence and enters the mounting groove.

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