Surface-mounted permanent magnet motor rotor structure

Abstract

The invention discloses a surface-mounted permanent magnet motor rotor structure, and the structure comprises a plurality of laminated layers which are superposed with one another and are welded with one another; and a plurality of groups of outer supporting parts are arranged, and the plurality of groups of outer supporting parts are uniformly and circumferentially distributed on the outer side of the laminated layer. The magnetic steel body is clamped through cooperation of the protruding block and the matching opening, the supporting strip tends to move outwards under the centrifugal effect, the opening end of the embedding opening is extruded, protruding faces protruding out of the two sides of the supporting strip extrude the opening end of the embedding opening, and generated acting force extends towards the first positioning block and the second positioning block on the two sides; when the rotor rotates, the protruding blocks and the matching openings are firmly matched, if the magnetic steel body and the supporting strips move outwards, the diameters of the magnetic steel body and the supporting strips are increased, namely the extrusion force generated on the outer supporting part is increased, in the rotating process of the rotor, the magnetic steel body is firmly matched, installation is convenient, and vibration and noise are effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motor rotors, and in particular to a surface mounted permanent magnet motor rotor structure. Background Art

[0002] Surface-mounted motor rotor is a type of rotor commonly used in electric motors or generators. Surface-mounted motor rotor refers to a motor rotor structure in which permanent magnets are directly attached to the outer surface of the rotor core. The permanent magnets are tile-shaped and located on the outer surface of the rotor core. The permanent magnets are fixed to the rotor core by adhesives or other means to form a stable magnetic field. The rotor core is usually made of laminated silicon steel sheets to improve the electromagnetic performance and heat dissipation performance of the motor. Surface-mounted motor rotors are widely used in various industrial control fields, such as machine tools, textile machinery, printing machinery, etc. Its simple structure, low manufacturing cost, and good control performance make surface-mounted motors very competitive in these fields.

[0003] The rotor core is made of laminated sheets, usually silicon steel sheets or nickel-iron alloy sheets. Multiple layers of iron sheets are stacked and glued together with a suitable primer or adhesive to form the core. The outer magnetic steel is usually directly attached to the outer surface of the rotor core. The most common methods are adhesive bonding, magnetic steel sleeve fixing and screw fixing.

[0004] When sticking magnets, ensure that the position of the magnets is accurate, and there should be no misalignment, displacement or magnet breakage. When using adhesives for bonding, pay attention to the curing time of the glue. Do not move or rotate the rotor before the glue is completely cured to prevent the magnets from being misaligned or falling off, and the processing is relatively complicated. When drilling holes in the magnets, the magnetic field lines of force will avoid the location of the holes, resulting in a decrease in the overall magnetic energy product and affecting the performance of the motor. When the magnet sleeve is fixed, a sheath made of stainless steel or carbon fiber material is used to constrain the surface of the magnet, but eddy current losses will be generated on the rotor surface and the heat dissipation will be affected. Therefore, for the surface-mounted permanent magnet motor rotor, it is an urgent problem for technical personnel in this field to efficiently complete the assembly of magnets, reduce the damage rate and maximize heat dissipation. Summary of the invention

[0005] The object of the present invention is to provide a surface mounted permanent magnet motor rotor structure to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a surface mounted permanent magnet motor rotor structure, comprising:

[0007] A stack, wherein the stack is provided in a plurality and overlapped with each other, and the plurality of stacks are welded to each other;

[0008] External support components are provided in a plurality of groups, wherein the plurality of groups of external support components are evenly distributed on the outer side of the laminate, and the external support components are integrally arranged with the laminate;

[0009] A plurality of magnetic steel bodies are provided, and the number of the magnetic steel bodies is the same as the number of the external support components. The magnetic steel bodies are attached to the outside of the stack and clamped between the two groups of external support components.

[0010] A plurality of support bars are provided and the number is the same as that of the outer support components. The support bars are clamped in the outer support components and are pushed against the magnetic steel body under the centrifugal force of rotation.

[0011] Furthermore, the laminate includes an outer layer and an inner layer, a plurality of circumferentially distributed support parts are provided between the outer layer and the inner layer, weight-reducing holes are formed between the support parts, and two ends of the support parts are respectively integrally arranged with the outer layer and the inner layer.

[0012] Furthermore, an inner hole penetrating the inner layer is provided on the axis of the inner layer, and the inner hole is used for installing a rotating shaft of the motor.

[0013] Furthermore, an oblique bar is provided inside the weight-reducing hole, the oblique bar is perpendicular to the stacking axis, and both ends of the oblique bar are fixed to the inner wall of the weight-reducing hole. The oblique bar is inclined and is used to drive the airflow movement when rotating.

[0014] Furthermore, a plurality of side holes are provided inside the support portion, and the side holes are used to connect two adjacent weight-reducing holes to drive the airflow movement.

[0015] Furthermore, the outer support component includes a positioning block 1 and a positioning block 2, and the positioning block 1 and the positioning block 2 are arranged as a group. The positioning block 1 and the positioning block 2 are oriented in opposite directions. The positioning block 1 and the positioning block 2 are both integrally arranged with the outer layer and extend outward from the outer side of the outer layer. The outer ends of the positioning block 1 and the positioning block 2 are fixed with relatively arranged protruding blocks. An installation portion is formed between the two groups of the outer support components, and the magnetic steel body is clamped in the installation portion. The outer side of the magnetic steel body has a mating opening that cooperates with the protruding block.

[0016] Furthermore, the bending parts of the positioning block 1 and the positioning block 2 have rounded corners, and the bending part of the magnetic steel body also has rounded corners. The inner and outer sides of the magnetic steel body are both arc-shaped, and the inner side is in contact with the outer side of the outer layer, and the outer side is flush with the positioning block 1 and the positioning block 2 on both sides. The two side edges of the magnetic steel body are respectively in contact with the positioning block 1 and the positioning block 2 on both sides.

[0017] Furthermore, the protruding block and the matching opening are both arranged in a quarter circle, and the protruding block faces one side of the mounting portion.

[0018] Furthermore, the outer walls of the positioning block 1 and the positioning block 2 on the side close to each other are both concave surfaces, and an embedding opening is formed between the positioning block 1 and the positioning block 2. The outer end of the embedding opening is connected to the outside world, and the support bar moves along the stacking axis and is embedded in the embedding opening.

[0019] Furthermore, the two ends of the support strip are respectively flush with the outermost laminated layers on both sides, and the two side edges of the support strip are protruding surfaces. The protruding surfaces on both sides of the support strip are fitted and squeezed with the recessed surfaces on both sides. The part of the protruding surface of the support strip extending outward is a flat surface, and the flat surface is also fitted in the inlay opening. The thickness between the flat surfaces on both sides of the support strip is less than the thickness of the protruding surfaces on both sides.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention clamps the magnetic steel body by cooperating with the protruding block and the matching opening, and the support bar tends to move outward under the centrifugal force, and squeezes the opening end of the embedding opening. The protruding surfaces on both sides of the support bar squeeze the opening end of the embedding opening, and the generated force extends to the positioning block 1 and the positioning block 2 on both sides, so that the protruding block and the matching opening are firmly matched. If the magnetic steel body and the support bar move outward, their diameters will increase, that is, the extrusion force generated on the external support component increases. During the rotation of the rotor, the magnetic steel body presents a firm fit, which is also convenient for installation and effectively reduces vibration and noise.

[0021] In addition, the extrusion force of the magnetic steel body and the support strip on the external support components is increased, which further ensures the reliable fixation of the magnetic steel body in the tangential and radial directions, and ensures that the magnetic steel body does not fall off;

[0022] In addition, there are several weight-reducing holes on the laminate, which can reduce the weight of the motor to the greatest extent. At the same time, the oblique bars and side holes are set to further dissipate heat, increase the contact area between the external environment and the rotor, and improve the heat dissipation capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a schematic diagram of the laminated main structure of the present invention;

[0026] Figure 3 It is a schematic diagram of the structure of the laminated heat dissipation part of the present invention;

[0027] Figure 4 It is a schematic diagram of the structure of the outer support component of the present invention;

[0028] Figure 5 It is a schematic diagram of the structure of the magnetic steel body of the present invention;

[0029] Figure 6 is a schematic diagram of the support bar structure of the present invention;

[0030] Figure 7 It is a schematic diagram of the stacked rotating state structure of the present invention.

[0031] In the figure: 1. stacking; 11. outer layer; 12. inner layer; 13. inner hole; 14. support part; 15. weight-reducing hole; 16. oblique strip; 17. side hole; 2. outer support component; 21. positioning block one; 22. positioning block two; 23. protruding block; 24. recessed surface; 25. inlay opening; 26. installation part; 3. magnetic steel body; 31. matching opening; 4. support strip; 41. protruding surface; 42. flat surface. DETAILED DESCRIPTION

[0032] 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.

[0033] See also Figure 1-7 , the present invention provides a technical solution: a surface mounted permanent magnet motor rotor structure, comprising: a laminate 1, an outer support component 2 and a magnetic steel body 3;

[0034] like Figure 1 As shown, there are several laminates 1 which are overlapped with each other, and several laminates 1 are welded to each other. The multiple laminates 1 arranged and welded can support the magnetic steel body 3. In addition, the stacking method can increase the strength and stability of the rotor, thereby improving the performance of the motor, and also help to optimize its electromagnetic performance or thermal performance. It should be noted that the laminate 1 material can be silicon steel sheets, and the contact surfaces between the silicon steel sheets will be closely fitted to reduce magnetic resistance and eddy current loss.

[0035] The outer support components 2 are provided with a plurality of groups, and the plurality of groups of outer support components 2 are evenly distributed on the outer side of the laminate 1, and the outer support components 2 and the laminate 1 are integrally arranged. It should be noted that the outer support components 2 are used to clamp the magnetic steel body 3, and the degree of clamping is better under the action of rotation;

[0036] There are several magnetic steel bodies 3, and the number of magnetic steel bodies 3 is the same as the number of external support parts 2. The magnetic steel bodies 3 are attached to the outside of the laminate 1 and clamped between two sets of external support parts 2. The attachment of the magnetic steel bodies 3 to the rotor surface can form a fixed magnetic field, so that the motor generates magnetic flux. This is the basis for the normal operation of the motor, because the existence of magnetic flux is the key to the motor's electromagnetic conversion and the conversion of electrical energy into mechanical energy;

[0037] There are a number of support bars 4 and the number is the same as that of the outer support part 2. The support bars 4 are clamped in the outer support part 2 and push against the magnetic steel body 3 under the centrifugal force of rotation to clamp the magnetic steel body 3 more tightly. The close fit and reasonable layout of the magnetic steel body 3 can reduce the eddy current loss and magnetic resistance loss during the operation of the motor, thereby reducing the heat generated by the motor. In addition, the fixing effect of the magnetic steel body 3 also helps to reduce the vibration and noise of the rotor and improve the running stability of the motor.

[0038] like Figure 2 As shown, the laminate 1 includes an outer layer 11 and an inner layer 12, and a plurality of support portions 14 are circumferentially distributed between the outer layer 11 and the inner layer 12. Weight-reducing holes 15 are formed between the support portions 14, and both ends of the support portions 14 are respectively integrated with the outer layer 11 and the inner layer 12. Under the action of the weight-reducing holes 15, the weight of the rotor can be reduced to the greatest extent, so that the equipment is faster and more flexible when starting, accelerating or decelerating. In addition, the use of unnecessary materials is minimized to achieve the goal of lightweight design, and the heat dissipation area of ​​the rotor is increased, which is beneficial to the dissipation and cooling of heat. This is particularly important in equipment such as motors that need to run for a long time and generate a large amount of heat.

[0039] An inner hole 13 penetrating the inner layer 12 is provided on the axis of the inner layer 12 . The inner hole 13 is used to install the rotating shaft of the motor. The rotating shaft is installed in the inner hole 13 to drive the rotation of the rotating shaft to realize the function of motor driving.

[0040] like Figure 3 As shown, the inside of the weight-reducing hole 15 is provided with an oblique bar 16, which is perpendicular to the axis of the laminate 1, and both ends of the oblique bar 16 are fixed to the inner wall of the weight-reducing hole 15, and the oblique bar 16 is inclined and is used to drive the airflow to move when rotating, wherein the oblique bar 16 increases the contact area between the rotor and the outside world, helps to increase the heat dissipation area of ​​the motor, promotes heat dissipation, thereby reducing the operating temperature of the motor, and improving the reliability and life of the motor. In addition, it helps to change the air flow pattern inside the motor, allowing the gas to move and increase heat dissipation.

[0041] A plurality of side holes 17 are provided inside the support portion 14 , and the side holes 17 are used to connect two adjacent weight-reducing holes 15 to drive the airflow to move, thereby increasing the heat dissipation area of ​​the rotor and improving the air circulation effect.

[0042] like Figure 4 As shown, the outer support component 2 includes a positioning block 1 21 and a positioning block 22, and a positioning block 1 21 and a positioning block 22 are set as a group. The positioning block 1 21 and the positioning block 22 face oppositely. The positioning block 1 21 and the positioning block 22 are both integrally arranged with the outer layer 11 and extend outward from the outer side of the outer layer 11. The outer ends of the positioning block 1 21 and the positioning block 22 are fixed with relatively arranged protruding blocks 23. A mounting portion 26 is formed between the two groups of outer support components 2, and the magnetic steel body 3 is clamped in the mounting portion 26. The outer side of the magnetic steel body 3 has a matching opening 31 that matches the protruding block 23. It should be noted that several groups of external support components 2 and several groups of magnetic steel bodies 3, the magnetic steel bodies 3 and the external support components 2 are distributed at intervals, so that the external support components 2 on both sides clamp the magnetic steel body 3 to achieve the effect of fixing.

[0043] The bent parts of the positioning block 1 21 and the positioning block 2 22 both have rounded corners, and the bent part of the magnetic steel body 3 also has rounded corners. The inner and outer sides of the magnetic steel body 3 are both arc-shaped, and the inner side thereof is in contact with the outer side of the outer layer 11, and the outer side thereof is flush with the positioning block 1 21 and the positioning block 2 22 on both sides. The two side edges of the magnetic steel body 3 are respectively in contact with the positioning block 1 21 and the positioning block 2 22 on both sides, so that the magnetic steel body 3 is in contact with the positioning block 1 21 and the positioning block 2 22 on both sides and the outer side of the outer layer 11, so that the position of the magnetic steel body 3 is limited, and the fastening and fitting design of the magnetic steel body 3 and the rotor simplifies the installation process, so that the magnetic steel body 3 can be installed on the rotor more easily and accurately, and the tight fitting reduces the maintenance problems caused by the loosening or falling off of the magnetic steel body 3, and reduces the maintenance difficulty and cost. It should also be noted that the magnetic steel body 3 is tightly fitted to the surface of the rotor to form a stable fixed magnetic field.

[0044] The protruding block 23 and the matching opening 31 are both arranged in a quarter circle, and the protruding block 23 faces one side of the mounting portion 26 for limiting the position of the magnetic steel body 3 .

[0045] The outer wall of the side where the positioning block 1 21 and the positioning block 2 22 are close to each other is a recessed surface 24, and an embedding opening 25 is formed between the positioning block 1 21 and the positioning block 2 22. The outer end of the embedding opening 25 is connected to the outside world, and the support bar 4 moves along the axial direction of the laminate 1 and is embedded in the embedding opening 25. After the support bar 4 is inserted into the embedding opening 25, the positioning block 1 21 and the positioning block 22 are supported, so that the positioning block 1 21 and the positioning block 22 clamp the magnetic steel body 3. In addition, when the rotor rotates, it is in a centrifugal state, so that the support bar 4 tends to move outward to achieve the expansion effect on the embedding opening 25. In addition, the magnetic steel body 3 also tends to move outward. During the rotation of the rotor, the tightening effect is maintained to achieve the tightening fit between the magnetic steel body 3 and the rotor, which helps to improve the load capacity of the motor.

[0046] like Figure 6 As shown, the two ends of the support bar 4 are flush with the outermost laminates 1 on both sides, and the two side edges of the support bar 4 are both protruding surfaces 41. The protruding surfaces 41 on both sides of the support bar 4 are fitted and squeezed with the recessed surfaces 24 on both sides. The part of the protruding surface 41 of the support bar 4 extending outward is a straight surface 42, and the straight surface 42 is also fitted in the embedding opening 25. The thickness between the straight surfaces 42 on both sides of the support bar 4 is less than the thickness of the protruding surfaces 41 on both sides. When the support bar 4 tends to move outward, its position will not change, but the squeezing effect on the inner wall of the embedding opening 25, that is, the recessed surface 24, is increased, avoiding local movement of the positioning block 1 21 and the positioning block 2 22, that is, increasing the clamping force on the magnetic steel body 3, to achieve a tight fit. The tight fit can reduce the loosening and wear of the magnetic steel body 3 during high-speed rotation.

[0047] The working principle of the present invention is as follows: the magnetic steel body 3 is clamped on the outside of a plurality of combined laminates 1 through the external support component 2, and the external support component 2 is limited by the support bar 4. When the rotor structure rotates, it has an outward centrifugal effect. Since the support bar 4 is clamped between the recessed surfaces 24 of the positioning block 1 21 and the positioning block 2 22, and the protruding block 23 cooperates with the matching opening 31 to clamp the magnetic steel body 3, the support bar 4 tends to move outward under the centrifugal effect, and squeezes the open end of the embedding opening 25, so that the protruding surfaces 41 protruding on both sides of the support bar 4 squeeze the open end of the embedding opening 25, and the generated force extends to the positioning block 1 21 and the positioning block 22 on both sides, so that the protruding block 23 and the matching opening 31 are firmly matched. In addition, the magnetic steel body 3 also has an outward centrifugal effect, which acts on the outer parts of the protruding block 23, the positioning block 1 21 and the positioning block 2 22. If the magnetic steel body 3 and the support bar 4 move outward, their diameters will increase, that is, the extrusion pressure on the external support component 2 will increase. Therefore, during the rotation of the rotor, the magnetic steel body 3 presents a firm fit, is easy to install, and effectively reduces vibration and noise.

[0048] In addition, during the operation of the rotor, the heat generated will produce local thermal expansion and contraction, which will increase the extrusion pressure of the magnetic steel body 3 and the support bar 4 on the external support component 2, further ensuring the reliable fixation of the magnetic steel body 3 in the tangential and radial directions, and ensuring that the magnetic steel body 3 does not fall off.

[0049] In addition, the laminate 1 is provided with a plurality of weight-reducing holes 15, which can reduce the weight of the motor to the greatest extent and increase the contact area between the rotor and the external environment. At the same time, the inclined bars 16 and the side holes 17 are arranged for further heat dissipation. When the rotor rotates, the gas in the laminate 1 can be pushed by the inclined bars 16 and pass through the side holes 17, thereby increasing the fluidity of the gas and increasing the contact area between the external environment and the rotor, thereby improving the heat dissipation capacity.

[0050] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0051] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A surface mounted permanent magnet motor rotor structure, characterized in that: include: A laminate (1), wherein a plurality of laminates (1) are provided and overlapped with each other, and a plurality of the laminates (1) are welded to each other; The outer support components (2) are provided in a plurality of groups, and the plurality of groups of the outer support components (2) are evenly distributed circumferentially on the outside of the laminate (1), and the outer support components (2) and the laminate (1) are integrally arranged; A plurality of magnetic steel bodies (3) are provided, and the number of the magnetic steel bodies (3) is the same as the number of the external support components (2); the magnetic steel bodies (3) are attached to the outside of the stack (1) and clamped between two groups of external support components (2); A plurality of support bars (4) are provided and the number of the support bars (4) is the same as the number of the outer support components (2). The support bars (4) are clamped in the outer support component (2) and are pushed against the magnetic steel body (3) under the centrifugal force of rotation.

2. The surface mounted permanent magnet motor rotor structure according to claim 1, characterized in that: The laminate (1) comprises an outer layer (11) and an inner layer (12), a plurality of circumferentially distributed support portions (14) are provided between the outer layer (11) and the inner layer (12), weight-reducing holes (15) are formed between the support portions (14), and two ends of the support portions (14) are respectively integrally arranged with the outer layer (11) and the inner layer (12).

3. The surface mounted permanent magnet motor rotor structure according to claim 2, characterized in that: An inner hole (13) penetrating the inner layer (12) is provided on the axis of the inner layer (12), and the inner hole (13) is used to install a rotating shaft of the motor.

4. The surface mounted permanent magnet motor rotor structure according to claim 2, characterized in that: An inclined strip (16) is provided inside the weight-reducing hole (15), the inclined strip (16) is perpendicular to the axis of the laminate (1), and both ends of the inclined strip (16) are fixed to the inner wall of the weight-reducing hole (15), and the inclined strip (16) is arranged to be inclined and is used to drive the airflow to move when rotating.

5. The surface mounted permanent magnet motor rotor structure according to claim 2, characterized in that: A plurality of side holes (17) are provided inside the support portion (14) and are arranged to penetrate the support portion (14). The side holes (17) are used to connect two adjacent weight-reducing holes (15) to drive the airflow to move.

6. The surface mounted permanent magnet motor rotor structure according to claim 2, characterized in that: The outer support component (2) comprises a positioning block 1 (21) and a positioning block 2 (22), wherein the positioning block 1 (21) and the positioning block 2 (22) are arranged as a group, the positioning block 1 (21) and the positioning block 2 (22) face opposite directions, the positioning block 1 (21) and the positioning block 2 (22) are both integrally arranged with the outer layer (11) and extend outward from the outer side of the outer layer (11), and the outer ends of the positioning block 1 (21) and the positioning block 2 (22) are both fixed with relatively arranged protruding blocks (23), and a mounting portion (26) is formed between the two groups of the outer support components (2), the magnetic steel body (3) is clamped on the mounting portion (26), and the outer side of the magnetic steel body (3) has a matching opening (31) that matches the protruding block (23).

7. The surface mounted permanent magnet motor rotor structure according to claim 6, characterized in that: The bent parts of the positioning block 1 (21) and the positioning block 2 (22) both have rounded corners, and the bent part of the magnetic steel body (3) also has rounded corners. The inner and outer sides of the magnetic steel body (3) are both arc-shaped, and the inner side thereof is in contact with the outer side of the outer layer (11), and the outer side thereof is flush with the positioning block 1 (21) and the positioning block 2 (22) on both sides. The two side edges of the magnetic steel body (3) are respectively in contact with the positioning block 1 (21) and the positioning block 2 (22) on both sides.

8. The surface mounted permanent magnet motor rotor structure according to claim 6, characterized in that: The protruding block (23) and the matching opening (31) are both arranged in a quarter circle, and the protruding block (23) faces one side of the mounting portion (26).

9. The surface mounted permanent magnet motor rotor structure according to claim 6, characterized in that: The outer walls of the positioning block 1 (21) and the positioning block 2 (22) on the sides close to each other are both recessed surfaces (24), an embedding opening (25) is formed between the positioning block 1 (21) and the positioning block 2 (22), the outer end of the embedding opening (25) is connected to the outside, and the support bar (4) moves along the axial direction of the laminate (1) and is embedded in the embedding opening (25).

10. The surface mounted permanent magnet motor rotor structure according to claim 9, characterized in that: The two ends of the support strip (4) are respectively flush with the outermost laminated layers (1) on both sides; both sides of the support strip (4) are protruding surfaces (41); the protruding surfaces (41) on both sides of the support strip (4) are fitted and pressed against the recessed surfaces (24) on both sides; the portion of the protruding surface (41) of the support strip (4) extending outwards is a straight surface (42); the straight surface (42) is also fitted in the inlay opening (25); and the thickness between the straight surfaces (42) on both sides of the support strip (4) is less than the thickness of the protruding surfaces (41) on both sides.

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