Energy-gathered magnetic mattress structure
By designing the energy-concentrating magnetic mattress structure, and utilizing the alternating polarity arrangement of the magnetic base, cover plate, and magnetic modules, combined with an elastic buffer layer, the problems of insufficient magnetic field strength and uneven distribution are solved, thereby improving the effects of deep magnetic therapy and personalized magnetic therapy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-18
- Publication Date
- 2026-03-10
AI Technical Summary
Existing magnetic therapy mattresses cannot effectively concentrate the magnetic energy generated by large-volume magnets, resulting in insufficient magnetic field strength, making it difficult to penetrate deeply into human tissues, and the magnetic field distribution is uneven.
The energy-concentrating magnetic mattress structure forms a magnetic unit through the design of a magnetic base, magnetic cover plate and magnetic modules. By using alternating polarity arrangement and magnetic network, a high-strength lateral closed magnetic circuit and vertical magnetic field are constructed. Combined with an elastic buffer layer to enhance magnetic field transmission, the magnetic field is directionally enhanced and evenly distributed.
It achieves deep penetration and uniform surface coverage of the magnetic field, improving the comprehensiveness and personalized adaptability of the magnetic therapy effect, and enhancing the magnetic therapy effect on key parts of the human body.
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Figure CN121621701A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of magnetic therapy home technology, specifically to an energy-concentrating magnetic mattress structure. Background Technology
[0002] Magnetotherapy, as a physical health care and adjunctive treatment method, is based on the principle of using the physiological effects of magnetic fields on human tissues to promote blood circulation, relieve muscle fatigue and improve metabolic function. Magnetic therapy mattresses have become the most common home magnetic therapy products due to their convenience and long-lasting effects. The principle is to set permanent magnets in the mattress to generate a static magnetic field that acts on the human body.
[0003] Most existing magnetic therapy mattresses use a large number of small magnetic particles or blocks evenly sewn or embedded in the fabric interlayer. This quantity advantage compensates for the low magnetic field strength and slow diffusion of a single magnet. However, because the energy product of a single small magnet is limited and the magnetic lines of force diverge, it cannot form a high-intensity focused magnetic field. The dispersed weak magnetic field can only act on the skin surface and cannot effectively penetrate deep muscles and tissues, resulting in poor magnetic therapy effects. To increase the magnetic field strength, existing technologies also use larger magnetic blocks. However, the magnetic field of large magnetic blocks still diverges in all directions, resulting in uneven magnetic field distribution on the mattress surface and the inability to concentrate the magnetic force in a directional manner. Therefore, there is an urgent need for a focused magnetic mattress structure that can efficiently concentrate the magnetic energy generated by large magnets, achieving directional enhancement and distribution of the magnetic field, thereby obtaining a better magnetic therapy effect. Summary of the Invention
[0004] The purpose of this invention is to solve the problems in the background art and provide an energy-concentrating magnetic mattress structure that can efficiently concentrate the magnetic energy generated by a large volume magnet, thereby achieving directional enhancement and distribution of the magnetic field.
[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A magnetic mattress structure includes a mattress body, which comprises a comfort layer, an elastic cushioning layer, a magnetic functional layer, and a base support layer arranged sequentially from top to bottom. The magnetic functional layer includes at least one magnetic focusing unit, which includes a magnetic base and a magnetic cover plate fixedly connected to the magnetic base. A magnetic module is also fixedly disposed within the magnetic base.
[0006] Preferably, both the magnetic base and the magnetic cover are made of a high magnetic permeability material. The magnetic base includes a magnetic cavity and a bottom opening. The magnetic cavity has an upward concave structure and the opening is oriented toward the elastic buffer layer. The bottom opening is oriented toward the base support layer. The magnetic cover covers and is fixed to the bottom opening of the magnetic base.
[0007] Preferably, the magnetic module is magnetized by axial magnetization and fixedly disposed in the magnetic focusing cavity. The external dimensions of the magnetic module are the same as those of the magnetic focusing cavity, and the working magnetic poles of the magnetic module are arranged facing the opening direction of the magnetic focusing cavity.
[0008] Preferably, the magnetically conductive base has a magnetically conductive protrusion extending into the cavity at the center of the bottom surface of the magnetically focusing cavity, and the surface of the non-working magnetic pole of the magnetic module has a recessed structure matching the magnetically conductive protrusion. The magnetically conductive protrusion is conical, dome-shaped, or prismatic in shape, and the cavity depth of the magnetically focusing cavity does not exceed the thickness of the magnetic module.
[0009] Preferably, the magnetic functional layer is provided with a plurality of magnetic focusing units, and the working magnetic poles of each magnetic module facing the opening direction of the magnetic base are arranged in an alternating polarity manner between adjacent magnetic focusing units.
[0010] Preferably, the multiple magnetic focusing units are arranged in zones according to the functional areas of the human body. The distribution density of the magnetic focusing units in the areas corresponding to the shoulders, back, and waist of the human body is greater than that in other areas.
[0011] Preferably, the magnetic functional layer is further provided with a magnetically conductive connecting piece, which is fixedly connected to each of the magnetic focusing units to form a magnetically conductive network.
[0012] Preferably, the magnetic focusing unit is embedded in the magnetic functional layer, and the upper surface of the magnetic module in the magnetic focusing unit is flush with the upper surface of the magnetic functional layer; the elastic buffer layer completely covers all the magnetic focusing units, and the elastic buffer layer includes, from top to bottom, a magnetic contact layer, a magnetic conduction layer and a support layer.
[0013] Preferably, the magnetic conduction layer includes a plurality of spaced magnetically conductive pillars and buffer pillars. The magnetically conductive pillars are made of a flexible substrate filled with magnetically conductive metal powder, and the magnetically conductive pillars are also embedded with helical magnetically conductive fiber bundles to enhance vertical magnetic conduction capability. The buffer pillars are used to provide auxiliary support and allow the magnetically conductive pillars to move vertically under pressure.
[0014] Preferably, the magnetic contact layer is an elastic substrate with mutually perpendicular alloy fiber bundles embedded inside to form a mesh, which provides a more uniform magnetic field to the surface layer; the support layer has a conical through hole, the position of which corresponds to the position of the magnetic post on the magnetic conduction layer, the magnetic post is embedded in the magnetic conduction layer and extends downward into the conical through hole, and an annular piece is also embedded on the bottom edge of the conical through hole, the conical through hole allows the magnetic post to be pressed in under pressure.
[0015] In summary, the beneficial effects of this invention are as follows: 1. The energy-concentrating magnetic mattress structure described in this invention, through the structural design of the magnetic base, magnetic protrusion and magnetic cover plate in the magnetic unit, gathers the magnetic lines of force that originally radiated outward from the large volume magnetic unit to the working surface facing the human body, effectively focusing the working magnetic field, making the magnetic field of the mattress have stronger penetrating power, and realizing deeper magnetic therapy with better magnetic therapy effect. 2. The energy-concentrating magnetic mattress structure described in this invention forms a high-intensity transverse closed magnetic circuit between adjacent magnetic units by arranging them in an alternating N / S polarity array. This achieves continuous and uniform magnetic field coverage on the mattress surface. The vertical magnetic field of the large-volume magnetic module is superimposed with the horizontal closed magnetic field, generating a multi-dimensional and multi-directional magnetic force, making the magnetic therapy effect more comprehensive. 3. The energy-concentrating magnetic mattress structure described in this invention features an elastic buffer layer that enhances magnetic conductivity, establishing a low magnetic resistance transmission channel from the magnetic unit to the human body surface. This further reduces the attenuation of the magnetic field during transmission. Furthermore, the magnetic columns within the magnetic conduction layer can be compressed to varying degrees in each zone according to the different pressures on different parts of the body. This results in a stronger magnetic field in high-pressure areas and a moderate magnetic field in low-pressure areas, achieving enhanced magnetic therapy in key areas through human body pressure and improving the personalized adaptive magnetic therapy effect of the mattress. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the main structure of the mattress of the present invention; Figure 2 This is a schematic diagram of the magnetic module arrangement structure of the present invention; Figure 3 This is a schematic diagram of the cross-sectional structure of the magnetic focusing unit of the present invention; Figure 4 This is a schematic diagram of the cross-sectional structure of the elastic buffer layer of the present invention.
[0017] The markings in the diagram are: 1. Comfort layer; 2. Elastic cushioning layer; 21. Magnetic contact layer; 211. Alloy fiber bundle; 22. Magnetic conduction layer; 221. Magnetic column; 222. Cushion column; 223. Magnetic metal powder; 224. Spiral magnetic fiber; 23. Support layer; 231. Conical through hole; 232. Annular piece; 3. Magnetic functional layer; 4. Base support layer; 5. Magnetic focusing unit; 51. Magnetic base; 52. Magnetic cover plate; 53. Magnetic cavity; 54. Bottom opening; 55. Magnetic protrusion; 6. Magnetic module; 61. Recessed structure; 7. Magnetic connecting piece. Detailed Implementation
[0018] The following specific embodiments are merely illustrative of the present invention and are not intended to limit the invention. Those skilled in the art can make modifications to these embodiments without contributing any inventive step after reading this specification, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.
[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0020] Example
[0021] according to Figures 1-4 As shown, an energy-concentrating magnetic mattress structure includes a mattress body, which includes a comfort layer 1, an elastic cushioning layer 2, a magnetic functional layer 3, and a base support layer 4 arranged sequentially from top to bottom. The magnetic functional layer 3 includes at least one magnetic focusing unit 5, which includes a magnetic conductive base 51 and a magnetic conductive cover plate 52 fixedly connected to the magnetic conductive base 51. A magnetic module 6 is also fixedly arranged inside the magnetic conductive base 51.
[0022] according to Figure 3 As shown, in this embodiment, both the magnetic base 51 and the magnetic cover plate 52 are made of high magnetic permeability material. The magnetic base 51 includes a magnetic cavity 53 and a bottom opening 54. The magnetic cavity 53 has an upwardly concave structure, with the opening facing the elastic buffer layer 2. The bottom opening 54 faces the base support layer 4. The magnetic cover plate 52 covers and is fixed to the bottom opening 54 of the magnetic base 51. The magnetic module 6 is magnetized by axial magnetization and fixedly disposed in the magnetic cavity 53. The external dimensions of the magnetic module 6 are the same as those of the magnetic cavity 53. The working magnetic poles of the magnetic module 6 are arranged facing the opening direction of the magnetic cavity 53. A magnetic protrusion 55 extending into the cavity is provided at the center of the bottom surface of the magnetic cavity 53 of the magnetic base 51. A recessed structure 61 matching the magnetic protrusion 55 is provided on the surface of the non-working magnetic poles of the magnetic module 6. The shape of the magnetic protrusion 55 is conical, dome-shaped or prism-shaped. The cavity depth of the magnetic cavity 53 does not exceed the thickness of the magnetic module 6.
[0023] The magnetic concentrating cavity 53 within the magnetic base 51 precisely matches the shape of the magnetic module 6. The magnetic concentrating cavity 53 is a concave cavity structure, with its opening directly opposite the upper elastic buffer layer 2. When the magnetic module 6 is installed inside the magnetic concentrating cavity 53, the surface of its working magnetic poles is flush with the surface of the magnetic functional layer 3 to maximize the output of magnetic lines of force. Both the magnetic base 51 and the magnetic cover plate 52 are made of high-permeability material. The magnetic cover plate 52 covers and is fixed to the bottom opening 54 of the magnetic base 51, together with the magnetic base 51 forming a... The magnetically conductive outer shell enveloping the magnetic module 6 completely covers the non-working magnetic poles and sides of the magnetic module 6. The bottom surface of the magnetic focusing cavity 53 of the magnetically conductive base 51 is provided with a magnetically conductive protrusion 55 extending into the cavity, which matches the recessed structure 61 on the non-working magnetic pole surface of the magnetic module 6. The design of the magnetically conductive protrusion 55 forms a path with extremely low magnetic resistance, which can effectively guide the magnetic lines of force emitted from the non-working magnetic poles of the magnetic module 6 and guide them to the side wall of the magnetically conductive base 51. After passing through the magnetically conductive cover plate 52 to form a circuit, the energy focusing effect is further optimized.
[0024] Through the high-permeability magnetic focusing unit 5, a low-resistivity path is constructed for the magnetic lines of force of the large-volume magnetic module 6. After the magnetic lines of force of the magnetic module 6 are emitted from the working magnetic pole, they enter the space above and act on the human body. The magnetic flux originally emitted from the non-working magnetic pole of the magnetic unit to the surroundings and downwards is guided and constrained by the magnetic protrusion 55 and the magnetic cover plate 52 on the magnetic base 51. These magnetic fluxes are eventually guided along the shell to the area near the working magnetic pole to converge, thereby greatly enhancing the magnetic flux density emitted from the direction of the working magnetic pole, thus realizing the convergence and directional enhancement of the magnetic field.
[0025] In this embodiment, a plurality of magnetic focusing units 5 are provided in the magnetic functional layer 3. The working magnetic pole polarity of each magnetic module 6 is arranged in the direction of the opening of the magnetic base 51, and the polarity is alternated between adjacent magnetic focusing units 5.
[0026] In the magnetic functional layer 3, multiple magnetic focusing units 5 are arranged in an array with alternating polarities. The working magnetic poles of the magnetic modules in two adjacent magnetic focusing units 5 have opposite polarities, with N and S poles alternating. The magnetic lines emitted by an N pole unit into the surface of the mattress are not all vertically upward; the magnetic lines at its edges bend outward. When arranged alternately, these bent magnetic lines are attracted by the adjacent S pole units with opposite polarities. Therefore, a high-density, high-gradient transverse closed magnetic loop is formed in the space above two adjacent magnetic modules 6. The magnetic lines of this loop are parallel to the mattress surface, so that the magnetic field generated by the magnetic module 6 can provide vertical penetration and also increase the magnetic force in the direction of the mattress surface. The large number of alternating magnetic units 6 makes the magnetic field distribution in the entire working area of the mattress more uniform and continuous, avoiding single-point stimulation that penetrates the magnetic therapy mattress. Furthermore, the combination of transverse and vertical magnetic lines can produce multi-directional magnetic force on the human body, making the magnetic effect of the mattress more comprehensive.
[0027] In this embodiment, multiple magnetic focusing units 5 are arranged in zones according to human functional areas. The distribution density of magnetic focusing units 5 is greater in the areas corresponding to the shoulders, back, and waist than in other areas.
[0028] The magnetic focusing unit 5 is located inside the magnetic functional layer 3. The magnetic functional layer 3 has several slots for installing the magnetic focusing unit 5. The magnetic focusing unit 5 inside the magnetic functional layer 3 is ergonomically arranged to correspond to the head and neck, shoulders, back, waist, arms and legs of the human body. The distribution density of the magnetic focusing unit 5 is greater in areas that are prone to strain and require intensive treatment, such as the shoulders, back and waist. This allows the mattress to provide precise magnetic therapy to the human body, further improving the user experience and effectiveness.
[0029] In this embodiment, a magnetically conductive connecting piece 7 is also provided on the magnetic functional layer 3, and the magnetically conductive connecting piece 7 is fixedly connected to each magnetically focusing unit 5 to form a magnetically conductive network.
[0030] Among them, multiple magnetic focusing units 5 are integrated or interconnected through magnetically conductive connecting pieces 7, forming a larger magnetically conductive network through the magnetically conductive connecting pieces 7, thereby balancing the magnetic field between each magnetic focusing unit 5, reducing the overall magnetic resistance, and making the magnetic field distribution of the entire magnetic functional layer 3 smoother and more stable.
[0031] according to Figure 4As shown, in this embodiment, the magnetic focusing unit 5 is embedded in the magnetic functional layer 3, and the upper surface of the magnetic module 6 in the magnetic focusing unit 5 is flush with the upper surface of the magnetic functional layer 3; the elastic buffer layer 2 completely covers all the magnetic focusing units 5, and the elastic buffer layer 2 includes, from top to bottom, a magnetic contact layer 21, a magnetic conduction layer 22, and a support layer 23; the magnetic conduction layer 22 includes a plurality of spaced magnetic conductive pillars 221 and buffer pillars 222, the magnetic conductive pillars 221 are flexible substrates filled with magnetic conductive metal powder 223, and the magnetic conductive pillars 221 are also embedded with spiral magnetic conductive fiber bundles 224 to enhance vertical magnetic conductivity; the buffer pillars 222 The magnetic contact layer 21 is used to provide auxiliary support and allow the magnetic column 221 to move vertically under pressure. The magnetic contact layer 21 is an elastic substrate with mutually perpendicular alloy fiber bundles 211 embedded inside to form a grid, which is used to provide a more uniform magnetic field to the surface. The support layer 23 has a tapered through hole 231, the position of which corresponds to the position of the magnetic column 221 on the magnetic conduction layer 22. The magnetic column 221 is embedded in the magnetic conduction layer 22 and extends downward into the tapered through hole 231. An annular piece 232 is also embedded on the bottom edge of the tapered through hole 231. The tapered through hole 231 allows the magnetic column 221 to be pressed in after being compressed.
[0032] The magnetic contact layer 21 uses slow-rebound memory foam as the substrate, and vertically arranged alloy fiber bundles 211 are embedded in the substrate. The alloy fiber bundles 211 are arranged to form a mesh. The alloy fiber bundles 211 use alloy fibers with high magnetic permeability. The alloy fiber bundles 211 can redistribute the magnetic field transmitted from the underlying magnetic functional layer 3 within the magnetic contact layer 21, making the magnetic field on the body surface more uniform. Compared with traditional mattresses without magnetic fibers, the alloy fiber bundles 211 can form a low magnetic resistance channel, thereby reducing the attenuation of the magnetic field on the mattress surface. The magnetic pillars 221 in the magnetic conduction layer 22 also use silicone as the matrix to provide sufficient flexibility. The interior is filled with magnetically conductive metal powder 223 to further enhance the magnetic pillars. With a magnetic permeability of 221, the magnetic pillars 221 are further enhanced by embedded spiral magnetic fiber bundles 224, which improve the vertical magnetic permeability. Each magnetic pillar 221 precisely corresponds to a magnetic focusing unit 5 below it. When human body pressure is applied to the mattress surface, the magnetic pillars 221 move downwards under pressure, bringing them closer to the magnetic focusing unit 5. When the pressure is high enough, the bottom of the magnetic pillar 221 directly contacts the magnetic module 6 on the magnetic focusing unit 5, forming a direct magnetic coupling. The magnetic field is transmitted upwards along the low magnetic resistance path inside the magnetic pillar 221, diffuses at the top of the pillar, and enters the magnetic contact layer 21, where it is evenly distributed by the alloy fiber bundles 211. The magnetic pillars 221 ensure that the magnetic field is transmitted upwards... The process is further enhanced by the presence of a cushioning column 222, which is made of elastic sponge without magnetic properties. It provides auxiliary support for the magnetic column 221, ensuring a flat mattress surface when not under pressure and allowing the magnetic column 221 to move downwards under pressure, while providing sufficient rebound support. The support layer 23 uses high-density hard sponge with several tapered through-holes 231 on its surface corresponding to the positions of the upper magnetic column 221. This ensures that the upper magnetic column 221 can align with the lower magnetic unit 5 and allows the magnetic column 221 to enter the tapered through-holes 231 without interference when moving downwards. Each tapered through-hole 231 also has an annular plate 232 at its bottom edge, allowing the magnetic column 221 to remain within the tapered through-hole 231 without interference. When the through-hole 231 is inside, it provides an initial upward guiding path for the magnetic field, while gathering the diffused magnetic field at the edge of the magnetic focusing unit 5, reducing the lateral leakage of the magnetic field to all sides; the magnetic conductive structure of the elastic buffer layer 2 is made of flexible material, so it can not only provide a comfortable lying environment, so that the human body will not feel the stiffness of the large-volume magnetic module 6, but also gather the surface magnetic field of the magnetic focusing unit 5, so that the magnetic field strength of the human body contact surface is further improved. Compared with the traditional magnetic therapy mattress, this embodiment does not simply allow the magnetic field to pass through, but actively collects, guides and enhances the magnetic field strength reaching the human body. Through the multi-layer magnetic conductive structure, the magnetic field leakage between the magnetic focusing units 5 is eliminated, and a more continuous and uniform magnetic field coverage is achieved.
Claims
1. A focused magnetic mattress pad structure comprising a mattress body, characterized by, The mattress body comprises, from top to bottom, a comfort layer (1), an elastic buffer layer (2), a magnetic function layer (3) and a base support layer (4), the magnetic function layer (3) comprises at least one magnetic aggregation unit (5), the magnetic aggregation unit (5) comprises a magnetic base (51) and a magnetic cover plate (52) fixedly connected with the magnetic base (51), and a magnetic module (6) is further fixedly arranged in the magnetic base (51).
2. The focused magnetic mattress pad structure of claim 1, wherein, The magnetic base (51) and the magnetic cover plate (52) are both made of high magnetic permeability material, the magnetic base (51) comprises a magnetic aggregation cavity (53) and a bottom opening (54), the magnetic aggregation cavity (53) is concave upward, the opening direction is arranged towards the elastic buffer layer (2), and the bottom opening (54) is arranged towards the base support layer (4); the magnetic cover plate (52) covers and is fixed on the bottom opening (54) of the magnetic base (51).
3. A focused magnetic mattress pad structure according to claim 2, wherein, The magnetic module (6) is magnetized in an axial magnetization mode and is fixedly arranged in the magnetic aggregation cavity (53), the outer dimension of the magnetic module (6) is the same as that of the magnetic aggregation cavity (53), and the working magnetic pole of the magnetic module (6) is arranged towards the opening direction of the magnetic aggregation cavity (53).
4. The focused magnetic mattress pad structure of claim 3, wherein, A magnetic protrusion (55) extending into the cavity is arranged at the center of the bottom surface of the magnetic aggregation cavity (53) of the magnetic base (51), a recess structure (61) matched with the magnetic protrusion (55) is arranged on the surface of the non-working magnetic pole of the magnetic module (6), the magnetic protrusion (55) is in the shape of a cone, a dome or a prism, and the cavity depth of the magnetic aggregation cavity (53) is not more than the thickness of the magnetic module (6).
5. The focused magnetic mattress pad structure of claim 1, wherein, A plurality of magnetic aggregation units (5) are arranged in the magnetic function layer (3), the working magnetic pole of each magnetic module (6) arranged towards the opening direction of the magnetic base (51) is arranged in an alternating polarity mode between adjacent magnetic aggregation units (5).
6. The focused magnetic mattress pad structure of claim 1, wherein, The plurality of magnetic aggregation units (5) are arranged in a partitioned manner according to human functional areas, and the distribution density of the magnetic aggregation units (5) in the areas corresponding to the shoulders, back and waist of the human body is greater than that in other areas.
7. The focused magnetic mattress pad structure of claim 1, wherein, A magnetic connection sheet (7) is further arranged on the magnetic function layer (3), and the magnetic connection sheet (7) is fixedly connected with each magnetic aggregation unit (5) to form a magnetic network.
8. The focused magnetic mattress pad structure of claim 1, wherein, The magnetic aggregation unit (5) is embedded in the magnetic function layer (3), the upper surface of the magnetic module (6) in the magnetic aggregation unit (5) is flush with the upper surface of the magnetic function layer (3); the elastic buffer layer (2) completely covers all the magnetic aggregation units (5), and the elastic buffer layer (2) comprises, from top to bottom, a magnetic contact layer (21), a magnetic conduction layer (22) and a supporting layer (23).
9. A focused magnetic mattress pad structure according to claim 8, wherein, The magnetic conducting layer (22) comprises a plurality of spaced magnetic conducting columns (221) and buffer columns (222), the magnetic conducting column (221) is filled with magnetic metal powder (223) inside the flexible base material, and the magnetic conducting column (221) is further embedded with spiral magnetic conducting fiber bundles (224) inside for enhancing vertical magnetic conducting capacity; the buffer column (222) is used for providing auxiliary support and allowing the magnetic conducting column (221) to move vertically under pressure.
10. The focused magnetic mattress pad structure of claim 9, wherein, The magnetic contact layer (21) is an elastic base material, embedded with alloy fiber bundles (211) arranged perpendicularly to each other and forming a grid shape, for providing a more uniform magnetic field to the surface layer; the supporting layer (23) is provided with a tapered through hole (231), the position of the tapered through hole (231) corresponds to the position of the magnetic conducting column (221) on the magnetic conducting layer (22), the magnetic conducting column (221) is embedded in the magnetic conducting layer (22) and extends downward to the inside of the tapered through hole (231), and the edge of the bottom end of the tapered through hole (231) is further embedded with an annular sheet (232), the tapered through hole (231) allows the magnetic conducting column (221) to be pressed in after being pressed.