Permanent magnet shaft generator rotor magnet steel assembly structure

Abstract

The application relates to a permanent magnet shaft generator rotor magnetic steel assembling structure and relates to the technical field of motor manufacturing. The outer circle of the rotor support is provided with a magnetic pole groove matched with the magnetic pole group; the magnetic pole group comprises a magnetic pole box, a bottom plate and a plurality of magnetic steel blocks, the plurality of magnetic steel blocks are assembled in the magnetic pole box in a non-magnetized state, the bottom plate is welded and fixedly sealed with the magnetic pole box, and the magnetic pole group is magnetized after being sealed; the magnetized magnetic pole group is integrally assembled in the magnetic pole groove, the both ends of the rotor support are provided with magnetic pole baffles for axially limiting the magnetic pole group, and the magnetic pole baffles are fixedly connected with the rotor support through fastening assemblies. The application assembles the non-magnetized magnetic steel blocks into the magnetic pole box and welds and seals the same, then magnetizes the magnetic pole group to form an independent magnetic pole group module, and then integrally assembles the magnetic pole group module into the magnetic pole groove of the rotor support, so that the magnetic force adsorption and crushing risks during the assembly of the magnetic steel blocks are effectively reduced, the assembly efficiency and precision are improved, the modular manufacturing is realized, and the convenient production of high-power motors is realized.

Description

Technical Field

[0001] This invention relates to the field of motor manufacturing technology, and in particular to a permanent magnet shaft generator rotor magnet assembly structure. Background Technology

[0002] With increasing demands for green environmental protection and energy conservation in marine engineering, permanent magnet shaft generators are being used more and more widely in marine propulsion systems. Permanent magnet shaft generators are typically directly coupled to the ship's main shaft, utilizing the surplus power of the main engine to generate electricity for the ship. Because marine shaft generators usually have high power output, their rotor structure requires a large number of permanent magnets (magnetic steel blocks) to provide a strong magnetic field.

[0003] In existing permanent magnet generator manufacturing processes, rotor magnet blocks are typically assembled piece by piece. In actual production, those skilled in the art usually directly attach each magnetized magnet block individually to the rotor support surface, or push the individual magnet blocks into the mounting slots of the rotor support using a sliding rail structure. During assembly, due to the extremely strong magnetic force of the magnet blocks, a huge electromagnetic attraction is generated when the magnetized magnet blocks approach the steel rotor support, making the alignment and positioning of multiple magnet blocks very difficult.

[0004] This traditional assembly method reveals significant technical flaws when producing high-power, multi-pole, multi-shaft generators. Due to the large size and quantity of the magnet blocks, the strong magnetic attraction easily causes them to jam when pushed into the mounting slot. Furthermore, because permanent magnet materials are inherently brittle, they are prone to breakage under strong magnetic impact or uneven stress, resulting in material scrap. In addition, the cumulative tolerances when axially splicing multiple magnet blocks are difficult to control, limiting the axial splicing length of the generator and significantly reducing production assembly efficiency, failing to meet the demands of modular, high-precision, mass-produced industrial applications. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a permanent magnet shaft-driven generator rotor magnet assembly structure.

[0006] This application provides a permanent magnet shaft-driven generator rotor magnet assembly structure, which adopts the following technical solution: A permanent magnet shaft-driven generator rotor magnet assembly structure includes a rotor support and a magnetic pole assembly. The outer circumference of the rotor support is provided with a magnetic pole groove that mates with the magnetic pole assembly. The magnetic pole assembly includes a magnetic pole box, a base plate, and multiple magnetic steel blocks. The multiple magnetic steel blocks are assembled in the magnetic pole box in an unmagnetized state, and the base plate is welded and sealed to the magnetic pole box. The magnetic pole assembly is then magnetized after sealing. The magnetized magnetic pole assembly is assembled as a whole in the magnetic pole groove, and magnetic pole baffles for axially limiting the magnetic pole assembly are installed at both ends of the rotor support. The magnetic pole baffles are fixedly connected to the rotor support by fastening components.

[0007] By adopting the above technical solution, multiple unmagnetized magnet blocks are first installed into the magnetic pole box during manufacturing, and then a base plate is welded on for sealing and fixation. Since the magnet blocks are non-magnetic at this stage, there is no magnetic interference during assembly, making alignment easy and preventing magnetic collision damage. After sealing, the entire magnetic pole assembly is magnetized to form a modular whole. Finally, the magnetized magnetic pole assembly is slid as a whole into the magnetic pole slots of the rotor support and axially fixed bidirectionally using magnetic pole baffles and fastening components at both ends. This solution avoids jamming and breakage during the assembly of individual magnet blocks, significantly improving assembly efficiency and accuracy, and facilitating later maintenance and replacement.

[0008] Optionally, the fastening assembly includes an external hexagonal bolt, a spring washer, a locking plate, and thread-locking adhesive. The external hexagonal bolt passes through the locking plate and the spring washer in sequence and is threadedly connected to the threaded hole at the end of the rotor bracket. The thread-locking adhesive is applied to the threaded section of the external hexagonal bolt.

[0009] By adopting the above technical solution, when screwing in the external hexagonal bolts at the end of the rotor support, spring washers, anti-loosening plates, and thread-locking adhesive are used in conjunction to achieve a multiple anti-loosening mechanism. In the environment of high-speed generator rotation and severe vibration, this effectively prevents the bolts from loosening due to alternating stress, ensuring the long-term stability of the axial locking force of the magnetic pole baffle on the magnetic pole assembly.

[0010] Optionally, the anti-loosening plate is a stainless steel anti-loosening plate. After the external hexagonal bolt reaches the preset tightening torque, the edge of the anti-loosening plate is raised diagonally to lock the head of the external hexagonal bolt.

[0011] By adopting the above technical solution, after the external hexagonal bolt is tightened to the specified pre-tightening torque, the edge of the anti-loosening plate is bent diagonally upward along the external hexagonal plane of the bolt head and pressed tightly by hand or special tools. This locks the rotational freedom of the external hexagonal bolt in terms of physical structure, providing a highly reliable mechanical anti-loosening effect and ensuring that the bolt will not loosen under long-term vibration conditions of the generator.

[0012] Optionally, multiple magnet blocks are arranged along the length of the magnetic pole box, and adjacent magnet blocks are bonded together with magnet block adhesive.

[0013] By adopting the above technical solution, multiple magnetic steel blocks arranged along the length direction are bonded and fixed using magnetic steel block adhesive. This solidifies the multiple unmagnetized magnetic steel blocks into a high-rigidity whole before welding and sealing, effectively preventing axial relative sliding, misalignment, or gaps between the magnetic steel blocks during magnetic pole box assembly, welding, overall magnetization, and subsequent generator operation. At the same time, the magnetic steel block adhesive layer plays a role in filling, vibration damping, and buffering, avoiding mechanical collisions and friction between adjacent magnetic steel blocks under high-speed generator rotation and severe ship vibration conditions, eliminating the risk of magnetic steel block edge breakage, and significantly improving the stability and long-term operational reliability of the internal structure of the magnetic pole group.

[0014] Optionally, the plurality of magnetic pole groups mounted on the rotor support are arranged in an alternating pattern of N and S poles.

[0015] By adopting the above technical solution, multiple magnetic pole groups are arranged alternately as N poles and S poles in the circumferential direction of the rotor, which can be used in conjunction with the stator winding to achieve efficient power conversion in subsequent use.

[0016] Optionally, threaded holes are provided on both ends of the rotor support, and the fastening assembly passes through the through hole on the magnetic pole baffle and engages with the threaded hole to press the magnetic pole baffle tightly onto the end face of the rotor support.

[0017] By adopting the above technical solution, threaded holes are directly machined on both ends of the rotor support, and the fastening components are directly screwed into the threaded holes through the through holes of the baffle. The structure is compact and the force is transmitted directly, which can reliably transmit axial impact load to the overall structure of the rotor support.

[0018] In summary, this application includes at least one of the following beneficial technical effects: 1. By pre-installing multiple unmagnetized magnet blocks into a stainless steel pole box and sealing it with a welded base plate, the entire assembly is then magnetized to form a modular pole group. Finally, the entire pole group is slid into the pole slot of the rotor bracket. This completely solves the problem of jamming and breakage caused by the huge magnetic attraction when assembling large-sized and numerous magnet blocks under strong magnetic conditions. This greatly simplifies the assembly process of permanent magnet shaft-driven generator rotors and significantly improves assembly efficiency.

[0019] 2. Multiple anti-loosening fastening components are used in conjunction with magnetic pole baffles for axial fixation. Combined with spring washers, thread sealant, and 1mm thick diagonally raised anti-loosening plates, it provides strong resistance to vibration and alternating loads, effectively preventing bolt loosening and axial movement of the magnet blocks caused by severe vibration during ship operation, and significantly improving the operational safety and service life of high-power permanent magnet shaft-driven generators. Attached Figure Description

[0020] Figure 1 This is a schematic diagram highlighting the rotor support.

[0021] Figure 2 This is a schematic diagram highlighting the magnetic pole group.

[0022] Figure 3 yes Figure 1 An enlarged schematic diagram of part A in the middle.

[0023] Figure 4 A schematic diagram of the overall structure of a permanent magnet shaft generator rotor magnet assembly structure. Figure 5 This is a cross-sectional schematic diagram highlighting the magnetic pole assembly mounted on the rotor support.

[0024] Figure 6 yes Figure 5 Enlarged schematic diagram of part B.

[0025] Explanation of reference numerals in the attached drawings: 1. Rotor support; 11. Magnetic pole slot; 2. Magnetic pole group; 21. Magnetic pole box; 22. Base plate; 23. Magnet block; 3. Magnetic pole baffle; 4. Fastening assembly; 41. Hex bolt; 42. Anti-loosening plate. Detailed Implementation

[0026] The present application will be further described in detail below with reference to all the accompanying drawings.

[0027] This application discloses an assembly structure for a permanent magnet shaft-driven generator rotor magnet.

[0028] Reference Figure 1 and Figure 2 A permanent magnet shaft-driven generator rotor magnet assembly structure includes a rotor support 1 and a magnetic pole assembly 2. The rotor support 1 is made of high-strength steel through welding and precision machining, and has a cylindrical structure.

[0029] In this embodiment, the steel used to manufacture the rotor support 1 can be Q355D low-alloy high-strength structural steel, Q460HN high-strength steel, or No. 45 quenched and tempered carbon structural steel, which can provide the generator rotor with extremely high mechanical strength to withstand the huge centrifugal force generated during high-speed rotation. Several magnetic pole slots 11 are axially formed on the outer cylindrical surface of the rotor support 1. The cross-sectional shape of the magnetic pole slots 11 matches the cross-sectional dimensions of the magnetic pole group 2, serving to accommodate and radially and circumferentially constrain the magnetic pole group 2. The number of magnetic pole slots 11 is designed according to the number of poles of the permanent magnet shaft-driven generator.

[0030] The magnetic pole assembly 2 includes a magnetic pole box 21, a base plate 22, and multiple magnetic steel blocks 23. In this embodiment, the magnetic pole box 21 is a thin-walled box structure with a wall thickness of 1 mm and an accommodating cavity with an opening facing one side. To ensure the normal distribution of the generator's magnetic circuit and not weaken the magnetic field strength, the magnetic pole box 21 must be made of non-magnetic material and must have excellent resistance to marine salt spray corrosion.

[0031] Therefore, the material of the magnetic pole box 21 is preferably 316 stainless steel (e.g., SUS316L austenitic stainless steel). In other embodiments, 304 stainless steel (e.g., SUS304 stainless steel) or duplex stainless steel with similar non-magnetic and corrosion-resistant properties (e.g., 2205 duplex stainless steel) can also be used. The material of the base plate 22 is the same as that of the magnetic pole box 21, which is also a 1mm thick 316 stainless steel plate or 304 stainless steel plate. Its planar dimensions match the opening of the magnetic pole box 21 and are used to seal the box after the magnet block 23 is inserted.

[0032] Multiple magnet blocks 23, in their unmagnetized state, are arranged sequentially along the axial direction and assembled inside the receiving cavity of the magnetic pole box 21. In this embodiment, the magnet blocks 23 can be made of high-performance neodymium iron boron permanent magnet material, or samarium cobalt permanent magnet material with better high-temperature resistance.

[0033] When assembling the magnet blocks 23, since the magnet blocks 23 are in a completely unmagnetized state (i.e., without magnetism), there is no strong magnetic repulsion or mutual attraction between the magnet blocks 23. Therefore, the assemblers can easily and safely arrange multiple magnet blocks 23 along the length of the magnetic pole box 21. Adjacent magnet blocks 23 are bonded together with magnet block 23 adhesive, so that multiple unmagnetized magnet blocks 23 are solidified into a high-rigidity whole before welding and sealing. This effectively prevents axial relative sliding, misalignment, or gaps between magnet blocks 23 during the assembly, welding, overall magnetization of the magnetic pole box 21, and subsequent operation of the generator. At the same time, the adhesive layer of the magnet blocks 23 plays a role in filling, vibration damping, and buffering, avoiding mechanical collisions and friction between adjacent magnet blocks 23 under high-speed rotation of the generator and severe vibration of the ship. This eliminates the hidden danger of corner breakage of the magnet blocks 23 and significantly improves the stability and long-term operational reliability of the internal structure of the magnetic pole group 2.

[0034] After the multiple unmagnetized magnet blocks 23 are neatly placed into the receiving cavity of the magnetic pole box 21, the base plate 22 is placed over the opening of the magnetic pole box 21, so that the base plate 22 contacts the edge of the magnetic pole box 21. The base plate 22 and the magnetic pole box 21 are then welded together to form a full-circle seal, completely sealing the multiple magnet blocks 23 in the sealed cavity formed by the magnetic pole box 21 and the base plate 22.

[0035] In this embodiment, the welding method can employ high-energy-density fiber laser welding, or it can employ manual tungsten inert gas welding or micro-beam plasma arc welding, which offer good protection. The weld formed by the welding has extremely high density, which can completely block external moisture, oil, salt spray, and other media from entering the interior of the magnetic pole box 21, thereby preventing the internal neodymium iron boron magnets 23 from undergoing oxidation and corrosion, which would lead to magnetic performance degradation.

[0036] After the base plate 22 and the magnetic pole box 21 are welded, sealed, and fixed, the multiple magnetic steel blocks 23 inside the magnetic pole assembly 2 are still in an unmagnetized state. The entire welded and sealed magnetic pole assembly 2 is placed in a dedicated integrated magnetizer for magnetization. The high-intensity magnetic field generated instantaneously by the magnetizer magnetizes the multiple magnetic steel blocks 23 inside the magnetic pole box 21 at once, thus completing the fabrication of the entire magnetic pole assembly 2. At this point, each magnetic pole assembly 2 becomes an independent magnetic pole module with a specific magnetic polarity (N pole or S pole).

[0037] Reference Figures 1 to 4 After being manufactured and magnetized, the magnetic pole assembly 2 is assembled into the magnetic pole slot 11 on the outer circumference of the rotor support 1. Specifically, during assembly, the magnetized magnetic pole assembly 2 is axially slid into the corresponding magnetic pole slot 11 from the end of the rotor support 1. Since the magnetic pole assembly 2 is an integral module tightly wrapped in a stainless steel shell, it will be attracted by a certain magnetic force during the sliding into the magnetic pole slot 11. Due to the physical isolation of the outer wall of the magnetic pole box 21 and the overall sliding design, the jamming and breakage caused by the direct collision of a single magnetic steel block 23 with the slot wall are effectively avoided. In order to form an alternating electromagnetic field on the rotor, the multiple magnetic pole assemblies 2 assembled on the rotor support 1 are arranged alternately in the circumferential direction according to the polarity of the N pole and the S pole.

[0038] After all the magnetic pole groups 2 have slid axially into the magnetic pole slots 11 of the rotor support 1, magnetic pole baffles 3 are installed on both axial end faces of the rotor support 1 to reliably limit the axial movement of the magnetic pole groups 2 and prevent them from axially shifting during generator operation. The magnetic pole baffles 3 are annular or fan-shaped, and their radial dimensions are sufficient to cover and block the end openings of all magnetic pole slots 11. The magnetic pole baffles 3 are rigidly fixed to the rotor support 1 by fastening components 4. Specifically, the two end faces of the rotor support 1 are machined with threaded holes that mate with the fastening components 4, and the magnetic pole baffles 3 are correspondingly provided with through holes.

[0039] Reference Figure 5 and Figure 6 The fastening assembly 4 includes an external hex bolt 41, a spring washer, a locking plate 42, and threadlocker. The external hex bolt 41 can be an 8.8 grade high-strength carbon steel bolt or an A4-80 grade stainless steel bolt. The spring washer provides initial elastic preload to prevent loosening due to minor vibrations. The locking plate 42 is a 1mm thick metal locking plate, made of stainless steel (such as 304 or 316 stainless steel) or carbon steel with good toughness (such as Q235A mild steel). The threadlocker can be Loctite 243 medium-strength threadlocker or Loctite 272 high-temperature resistant high-strength threadlocker.

[0040] During the specific fastening and assembly process, threadlocker is first evenly applied to the internal threads of the threaded hole at the end of the rotor bracket 1 or to the threaded section of the external hexagon bolt 41. Then, the external hexagon bolt 41 is passed through the anti-loosening plate 42 and the spring washer in sequence, then through the through hole on the magnetic pole baffle 3, and finally screwed into the threaded hole on the end face of the rotor bracket 1. A torque wrench is used to tighten the external hexagon bolt 41 to the preset tightening torque, so that the spring washer is completely flattened and the magnetic pole baffle 3 is firmly pressed against the end face of the rotor bracket 1. After the bolt is fully tightened, a special tool or manually is used to bend the two diagonal edges of the anti-loosening plate 42 upwards along the edge of the head of the external hexagon bolt 41, so that it fits tightly against the external hexagonal plane of the bolt head, thereby achieving secondary anti-loosening locking of the bolt at the physical structural level.

[0041] Through the combined effect of the above multiple anti-loosening measures, even under the harsh working conditions of severe ship vibration, high-speed rotation and alternating stress, the fastening component 4 can maintain a stable preload for a long time, ensuring that the axial limiting function of the magnetic pole baffle 3 on the magnetic pole group 2 is always effective, preventing the magnetic pole group 2 from axially moving, thereby ensuring the long-term stable operation and safe use of the permanent magnet shaft generator.

[0042] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A permanent magnet shaft-driven generator rotor magnet assembly structure, characterized in that, The system includes a rotor support (1) and a magnetic pole assembly (2). The outer circumference of the rotor support (1) is provided with a magnetic pole groove (11) that cooperates with the magnetic pole assembly (2). The magnetic pole assembly (2) includes a magnetic pole box (21), a base plate (22), and multiple magnetic steel blocks (23). The multiple magnetic steel blocks (23) are assembled in the magnetic pole box (21) in an unmagnetized state. The base plate (22) is welded and sealed to the magnetic pole box (21). The magnetic pole assembly (2) is magnetized after being sealed. The magnetized magnetic pole assembly (2) is assembled as a whole in the magnetic pole groove (11). The rotor support (1) is equipped with magnetic pole baffles (3) at both ends for axially limiting the magnetic pole assembly (2). The magnetic pole baffles (3) are fixedly connected to the rotor support (1) by fastening components (4).

2. The permanent magnet shaft generator rotor magnet assembly structure according to claim 1, characterized in that, The fastening assembly (4) includes an external hexagonal bolt (41), a spring washer, a locking plate (42), and thread-locking adhesive. The external hexagonal bolt (41) passes through the locking plate (42) and the spring washer in sequence and is threadedly connected to the threaded hole at the end of the rotor bracket (1). The thread-locking adhesive is applied to the threaded section of the external hexagonal bolt (41).

3. The permanent magnet shaft generator rotor magnet assembly structure according to claim 2, characterized in that, The anti-loosening plate (42) is a stainless steel anti-loosening plate (42). After the external hexagonal bolt (41) reaches the preset tightening torque, the edge of the anti-loosening plate (42) is raised diagonally to lock the head of the external hexagonal bolt (41).

4. The permanent magnet shaft generator rotor magnet assembly structure according to claim 1, characterized in that, Multiple magnetic steel blocks (23) are arranged along the length of the magnetic pole box (21), and adjacent magnetic steel blocks (23) are bonded together by magnetic steel block (23) adhesive.

5. The permanent magnet shaft generator rotor magnet assembly structure according to claim 1, characterized in that, The multiple magnetic pole groups (2) assembled on the rotor support (1) are arranged in alternating polarities of N pole and S pole.

6. The permanent magnet shaft generator rotor magnet assembly structure according to claim 2, characterized in that, The rotor support (1) has threaded holes on both ends. The fastening assembly (4) passes through the through hole on the magnetic pole baffle (3) and engages with the threaded hole to press the magnetic pole baffle (3) against the end face of the rotor support (1).

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