Low electromagnetic interference magnetic connection method

Abstract

The invention discloses a low-electromagnetic interference magnetic connection method, which comprises the following steps of: S1, generating a magnetic field with set strength by utilizing a magnet of a base, embedding a magnetic material into a connected end, and enabling the magnetic material to be subjected to magnetic attraction in the magnetic field; s2, a conical ferromagnetic material shielding case and a conical ferrite shielding case are sequentially arranged outside the magnet and the magnetic material in a surrounding mode, the two shielding cases are combined to serve as a magnetic field shielding case, and an opening in the bottom face of the conical magnetic field shielding case serves as a magnetic force connecting face; and S3, on the basis of the influence of the ratio of the bottom surface radius of the conical magnetic field shielding cover to the magnet radius on the adsorption force, the adaptive radius ratio is calculated in combination with the magnetic permeability and the magnetic field intensity, and the magnetic attraction force meeting the requirement is provided for magnetic attraction connection. According to the low-electromagnetic-interference magnetic connection method disclosed by the invention, electromagnetic radiation and electromagnetic induction interference are effectively inhibited on the basis of ensuring the magnetic connection strength and convenience, and normal work of peripheral sensitive electronic elements is protected.

Description

Technical Field

[0001] This invention belongs to the field of magnetic connection technology, specifically relating to a low electromagnetic interference magnetic connection method. Background Technology

[0002] With the rapid development of electronic technology towards higher precision, higher integration, and higher frequency, the sensitivity of various electronic devices and systems to the electromagnetic environment has significantly increased. Electromagnetic interference has become a key factor affecting the reliability, stability, and safety of equipment.

[0003] Magnetic connection technology is widely used in electronic device component connections due to its outstanding advantages such as no mechanical contact wear, convenient connection and separation, and overload protection. However, existing magnetic connection technologies generally suffer from electromagnetic interference problems: on the one hand, the magnets used in traditional magnetic connections are mostly open magnetic field structures, and the external leakage magnetic field will generate strong spatial electromagnetic radiation. This radiation can be coupled to sensitive circuits or components such as high-frequency signal processing circuits, precision sensors, or low-noise amplifiers through electromagnetic induction, leading to signal distortion, increased measurement errors, and even equipment failure. On the other hand, when traditional magnetic connection structures are in dynamic working environments such as component insertion and removal, vibration, etc., changes in the magnetic field gap will generate induced electromotive force in surrounding metal components or conductive paths, forming interference currents. This not only causes energy loss but also affects the normal operation of adjacent electronic circuits through conduction paths.

[0004] Currently, existing technologies mostly reduce interference by adjusting the layout of magnets and sensitive circuits, but cannot achieve full-space electromagnetic interference suppression. To meet the stringent application requirements of precision electronic equipment, medical instruments, aerospace, and other fields, there is an urgent need for a new magnetic connection method that can achieve low electromagnetic radiation and low induced interference while ensuring connection strength and convenience. Summary of the Invention

[0005] The main objective of this invention is to provide a low-electromagnetic-interference magnetic connection method that, while ensuring the strength and convenience of the magnetic connection, effectively suppresses electromagnetic radiation and electromagnetic induction interference, and protects the normal operation of surrounding sensitive electronic components.

[0006] To achieve the above objectives, the present invention provides a low electromagnetic interference magnetic connection method, comprising the following steps: Step S1: Use the magnet on the base to generate a magnetic field of a set intensity, and embed magnetic material in the connected end so that the magnetic material is attracted by magnetic force in the magnetic field. Step S2: Surround the magnet and magnetic material in sequence with a conical ferromagnetic material shield and a conical ferrite shield. The two shields are combined to form a magnetic field shield. The bottom opening of the conical magnetic field shield serves as the magnetic connection surface. Step S3: Based on the influence of the ratio of the bottom radius of the conical magnetic field shield to the magnet radius on the adsorption force, and combined with the permeability and magnetic field strength, calculate the appropriate radius ratio to provide the required magnetic attraction force for magnetic connection; Step S4: The base and the magnetic field shield of the connected end are exactly the same size. When the two are connected, the two conical magnetic field shields combine to form a closed shielding space. At the same time, the magnetic field materials attract and connect with each other, while the external ferromagnetic material forms a complete enclosure to shield the magnetic field from leakage. Furthermore, the magnetic field is isolated by ferrite.

[0007] As a further preferred embodiment of the above technical solution, in step S1, the magnet embedded in the base is a permanent magnet, and the calculation formula for generating a magnetic field of a set intensity is as follows: ; The formula for calculating the magnetic attraction force experienced by a ferromagnetic material embedded at the connected end in a magnetic field is as follows: ; Where B represents the magnetic flux density. The permeability of free space, The permeability of ferromagnetic materials, For the magnetic moment of the magnet, To find the volume integral of the magnet, A point in the magnet, For any point in space, The length of the cylinder The average magnetic field strength at the center of the cylinder is... Let F be the change in magnetic field strength per unit length, and F be the magnetic attraction force.

[0008] As a further preferred technical solution to the above technical solution, in step S2: For the base: The cylindrical magnet embedded in the base is uniform. The magnet and the conical ferromagnetic material shield are rigidly connected with non-magnetic glue. When connecting, ensure that the axis of the conical ferromagnetic material shield and the axis of the cylindrical magnet are on the same straight line. The same connection treatment is used between the conical ferromagnetic material shield and the conical ferrite shield. For the connected ends, a conical ferromagnetic material shield and a conical ferrite shield are also wrapped around the cylindrical magnetic material, ensuring that the axes of the three are the same, and a non-magnetic adhesive is used for hard connection.

[0009] As a further preferred embodiment of the above technical solution, in step S3, the diameter of the magnet and the diameter of the magnetic field shield are related to the magnetic attraction force generated by the magnet, and the formula for calculating the magnetic attraction force is as follows: ; Where B is the magnetic flux density at the magnet's operating point. The effective adsorption area, i.e., the opening area of ​​the magnetic field shield, The permeability of free space, This is the magnetic circuit efficiency factor, which is not a fixed value but is related to the radius ratio and the magnetic permeability of the shielding material. Its derivation relationship is as follows: ; in, The length of the air gap. This represents the axial length of the magnet. The relative permeability of the magnet. Where is the radius of the magnet. The radius of the bottom surface of the shielding cover.

[0010] As a further preferred technical solution to the above technical solution, in step S4, after being in the connected state, the two conical shields combine to form a closed shielding space, realizing the mutual attraction and connection of the magnetic field materials. At the same time, the outer conical ferromagnetic material shield forms a complete enclosure to shield the magnetic field from leakage, and further isolation is achieved through the conical ferrite shield. The formula for calculating the external magnetic field strength of the magnetic field shield is as follows: ; ; in, To increase the magnetic field strength behind the shield, The magnetic field strength without a shield. The attenuation rate is due to the magnetic shunt effect. Let t be the absolute magnetic permeability of the shielding material, t be the thickness of the shield, and d be the characteristic dimension of the shield.

[0011] As a further preferred technical solution to the above technical solution, the magnet of the base is an electromagnet, and the formula for calculating the magnetic field strength generated is as follows: ; The ferromagnetic material at the connected end is a magnet, and the formula for calculating the force it experiences in the magnetic field is as follows: ; Where B represents the magnetic flux density. The permeability of free space, Where is the relative permeability of the core material, N is the number of coil turns, I is the current through the coil, L is the magnetic circuit length, F is the magnetic attraction force, and A is the effective adsorption area.

[0012] The beneficial effects of this invention are as follows: 1. The magnetic connection design with assembly shielding cover is adopted, which effectively suppresses electromagnetic radiation and electromagnetic induction interference while ensuring the convenience and strength of magnetic connection, and avoids affecting surrounding sensitive components and circuits. 2. An innovative conical shielding structure is adopted, which maximizes the cross-sectional area at the connection point to meet the magnetic attraction requirements. Furthermore, the cross-sectional area decreases as the distance from the connection end increases, gradually enhancing the constraint effect on the magnetic field and achieving directional constraint and efficient shielding of the magnetic field. 3. A scientific evaluation method for the magnet radius and the bottom radius of the shield is proposed, which can quickly select the appropriate size range and significantly improve design efficiency; 4. The shape of the shield is not limited to a cone shape. As long as the cross-section is negatively correlated with the connection distance, it can be used in a wide range of scenarios with strong flexibility and adaptability. Attached Figure Description

[0013] Figure 1 This is an overall schematic diagram of the present invention.

[0014] Figure 2 This is a cross-sectional view of the present invention. Detailed Implementation

[0015] The following description is intended to disclose the present invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the invention.

[0016] In the preferred embodiments of the present invention, those skilled in the art should note that the magnets, connected ends, etc. involved in the present invention can be regarded as prior art.

[0017] Preferred embodiment.

[0018] like Figure 1-2 As shown, this invention discloses a low electromagnetic interference magnetic connection method, comprising the following steps: Step S1: Use the magnet on the base to generate a magnetic field of a set intensity, and embed magnetic material in the connected end so that the magnetic material is attracted by magnetic force in the magnetic field. Step S2: Surround the magnet and magnetic material in sequence with a conical ferromagnetic material shield and a conical ferrite shield. The two shields are combined to form a magnetic field shield. The bottom opening of the conical magnetic field shield serves as the magnetic connection surface. Step S3: Based on the influence of the ratio of the bottom radius of the conical magnetic field shield to the magnet radius on the adsorption force, and combined with the permeability and magnetic field strength, calculate the appropriate radius ratio to provide the required magnetic attraction force for magnetic connection; Step S4: The base and the magnetic field shield of the connected end are exactly the same size. When the two are connected, the two conical magnetic field shields combine to form a closed shielding space. At the same time, the magnetic field materials attract and connect with each other, while the external ferromagnetic material forms a complete enclosure to shield the magnetic field from leakage. Furthermore, the magnetic field is isolated by ferrite.

[0019] Specifically, the magnet embedded in the base is a permanent magnet, and the calculation formula for generating a magnetic field of a set intensity is as follows: ; The formula for calculating the magnetic attraction force experienced by a ferromagnetic material embedded at the connected end in a magnetic field is as follows: ; Where B represents the magnetic flux density. The permeability of free space, The permeability of ferromagnetic materials, For the magnetic moment of the magnet, To find the volume integral of the magnet, It is a point in the magnet (the point where the magnetic dipole is located). For any point in space, The length of the cylinder The average magnetic field strength at the center of the cylinder is... Let F be the change in magnetic field strength per unit length, and F be the magnetic attraction force.

[0020] More specifically, in step S2, a double-layered conical shield is used to reduce interference from the magnetic connection device while ensuring sufficient magnetic attraction, wherein: For the base: The cylindrical magnet embedded in the base is uniform. The magnet and the conical ferromagnetic material shield are rigidly connected with non-magnetic glue. When connecting, ensure that the axis of the conical ferromagnetic material shield and the axis of the cylindrical magnet are on the same straight line. The same connection treatment is used between the conical ferromagnetic material shield and the conical ferrite shield. For the connected end, a conical ferromagnetic material shield and a conical ferrite shield are also wrapped around the cylindrical magnetic material, ensuring that the axes of the three are the same, and are also rigidly connected using non-magnetic adhesive (the bottom surfaces of the conical ferromagnetic material shield and the conical ferrite shield are on the same plane; the bottom surface of the cylindrical magnet or cylindrical magnetic material is slightly higher than the bottom surface of the conical magnetic field shield, with a height difference of 0.01mm).

[0021] Furthermore, in step S3, the diameter of the magnet and the diameter of the magnetic field shield are related to the magnetic attraction force generated by the magnet. The formula for calculating the magnetic attraction force is as follows: ; Where B is the magnetic flux density at the magnet's operating point. The effective adsorption area, i.e., the opening area of ​​the magnetic field shield (the area of ​​the cone's base), is... ), The permeability of free space, This is the magnetic circuit efficiency factor, which is not a fixed value. It is related to the radius ratio (the ratio of the bottom radius of the shield to the radius of the magnet) and the permeability of the shield material. The derivation relationship is as follows: ; in, The length of the air gap. This represents the axial length of the magnet. The relative permeability of the magnet. Where is the radius of the magnet. The radius of the bottom surface of the shielding cover.

[0022] Furthermore, in step S4, after being connected, the two conical shields combine to form a closed shielding space. This achieves mutual attraction and connection between the magnetic field materials, while the outer conical ferromagnetic material shield forms a complete enclosure to prevent magnetic field leakage. Isolation is further achieved through the conical ferrite shield. The formula for calculating the external magnetic field strength of the magnetic field shield is as follows: ; ; in, To increase the magnetic field strength behind the shield, The magnetic field strength without a shield. The attenuation rate is due to the magnetic shunt effect. Let t be the absolute magnetic permeability of the shielding material, t be the thickness of the shield, and d be the characteristic dimension of the shield.

[0023] Preferably, the magnet in the base is an electromagnet, and the formula for calculating the magnetic field strength is as follows: ; The ferromagnetic material at the connected end is a magnet, and the formula for calculating the force it experiences in the magnetic field is as follows: ; Where B represents the magnetic flux density. The permeability of free space, Where is the relative permeability of the core material, N is the number of coil turns, I is the current through the coil, L is the magnetic circuit length, F is the magnetic attraction force, and A is the effective adsorption area.

[0024] Figure 1 The diagram shows the overall structure, which includes a cone embedded in the base and a cone embedded in the connected end. When the connected end is also embedded in a magnetic material, the magnetic poles on the bottom surface should be opposite to those on the base.

[0025] It is worth mentioning that the technical features such as magnets and connected ends involved in this patent application should be regarded as prior art. The specific structure, working principle, and possible control methods and spatial arrangement of these technical features can be adopted using conventional choices in the field, and should not be regarded as the inventive point of this patent. This patent will not be further elaborated in detail.

[0026] For those skilled in the art, modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the protection scope of this invention.

Claims

1. A low-electromagnetic-interference magnetic connection method, characterized in that, Includes the following steps: Step S1: Use the magnet on the base to generate a magnetic field of a set intensity, and embed magnetic material in the connected end so that the magnetic material is attracted by magnetic force in the magnetic field. Step S2: Surround the magnet and magnetic material in sequence with a conical ferromagnetic material shield and a conical ferrite shield. The two shields are combined to form a magnetic field shield. The bottom opening of the conical magnetic field shield serves as the magnetic connection surface. Step S3: Based on the influence of the ratio of the bottom radius of the conical magnetic field shield to the magnet radius on the adsorption force, and combined with the permeability and magnetic field strength, calculate the appropriate radius ratio to provide the required magnetic attraction force for magnetic connection; Step S4: The base and the magnetic field shield of the connected end are exactly the same size. When the two are connected, the two conical magnetic field shields combine to form a closed shielding space. At the same time, the magnetic field materials attract and connect with each other, while the external ferromagnetic material forms a complete enclosure to shield the magnetic field from leakage. Furthermore, the magnetic field is isolated by ferrite.

2. The low electromagnetic interference magnetic connection method according to claim 1, characterized in that, In step S1, the magnet embedded in the base is a permanent magnet, and the calculation formula for generating a magnetic field of a set intensity is as follows: ； The formula for calculating the magnetic attraction force experienced by a ferromagnetic material embedded at the connected end in a magnetic field is as follows: ； Where B represents the magnetic flux density. The permeability of free space, The permeability of ferromagnetic materials, For the magnetic moment of the magnet, To find the volume integral of the magnet, A point in the magnet, For any point in space, The length of the cylinder The average magnetic field strength at the center of the cylinder is... Let F be the change in magnetic field strength per unit length, and F be the magnetic attraction force.

3. The low electromagnetic interference magnetic connection method according to claim 2, characterized in that, In step S2: For the base: The cylindrical magnet embedded in the base is uniform. The magnet and the conical ferromagnetic material shield are rigidly connected with non-magnetic glue. When connecting, ensure that the axis of the conical ferromagnetic material shield and the axis of the cylindrical magnet are on the same straight line. The same connection treatment is used between the conical ferromagnetic material shield and the conical ferrite shield. For the connected ends, a conical ferromagnetic material shield and a conical ferrite shield are also wrapped around the cylindrical magnetic material, ensuring that the axes of the three are the same, and a non-magnetic adhesive is used for hard connection.

4. The low electromagnetic interference magnetic connection method according to claim 3, characterized in that, In step S3, the diameter of the magnet and the diameter of the magnetic field shield are related to the magnetic attraction force generated by the magnet. The formula for calculating the magnetic attraction force is as follows: ； Where B is the magnetic flux density at the magnet's operating point. The effective adsorption area, i.e., the opening area of ​​the magnetic field shield, The permeability of free space, This is the magnetic circuit efficiency factor, which is not a fixed value but is related to the radius ratio and the magnetic permeability of the shielding material. Its derivation relationship is as follows: ； in, The length of the air gap. This is the axial length of the magnet. The relative permeability of the magnet. Let be the radius of the magnet. The radius of the bottom surface of the shielding cover.

5. The low electromagnetic interference magnetic connection method according to claim 4, characterized in that, In step S4, after being connected, the two conical shields combine to form a closed shielding space, achieving mutual attraction and connection between the magnetic field materials. At the same time, the outer conical ferromagnetic material shield forms a complete enclosure to prevent magnetic field leakage, and further isolation is achieved through the conical ferrite shield. The formula for calculating the external magnetic field strength of the magnetic field shield is as follows: ； ； in, To increase the magnetic field strength behind the shield, The magnetic field strength without a shield. The attenuation rate is due to the magnetic shunt effect. Let t be the absolute magnetic permeability of the shielding material, t be the thickness of the shield, and d be the characteristic dimension of the shield.

6. The low electromagnetic interference magnetic connection method according to claim 1, characterized in that, The magnet in the base is an electromagnet, and the formula for calculating the strength of the magnetic field it generates is as follows: ； The ferromagnetic material at the connected end is a magnet, and the formula for calculating the force it experiences in the magnetic field is as follows: ； Where B represents the magnetic flux density. The permeability of free space, Where is the relative permeability of the core material, N is the number of coil turns, I is the current through the coil, L is the magnetic circuit length, F is the magnetic attraction force, and A is the effective adsorption area.

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