Preparation method for magnetic-flux-concentrating magnet, and magnetic-flux-concentrating magnet and loudspeaker
Patent Information
- Application Number
- PCT/CN2025/088843
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2026-10-22
Smart Images
Figure CN2025088843_22102026_PF_FP_ABST
Abstract
Description
A method for preparing a polymagnetic steel, the polymagnetic steel and a loudspeaker Technical Field
[0001] This invention relates to the field of electronic product technology, and in particular to a method for preparing a polymagnetic steel, the polymagnetic steel, and a loudspeaker. Background Technology
[0002] With the development of electronic technology, portable consumer electronic devices are becoming increasingly popular, such as mobile phones, handheld game consoles, navigation devices, or handheld multimedia entertainment devices. These electronic devices generally use voice for system feedback, such as incoming call notifications and navigation prompts on mobile phones, all of which utilize speakers. Technical issues
[0003] Traditional loudspeakers use magnets magnetized with a single uniform magnetic field, as shown in Figure 1. This method results in magnetization in the same direction across all regions of the magnet. In the loudspeaker's magnetic circuit system, a pole core is typically used to concentrate the magnetism, generating a strong magnetic field at the magnetic gap. This structure leads to the pole core occupying a significant amount of space in the magnetic circuit system, reducing the magnet's volume and magnetic field strength. Furthermore, due to the saturation magnetization of the pole core clamping plate, the magnetic circuit experiences substantial magnetic leakage.
[0004] Therefore, it is necessary to propose a new technical solution to address the above problems. Technical solutions
[0005] To address the problems of low magnetic field strength and magnetic leakage caused by the use of core magnetization in existing technologies, the first aspect of this invention provides a method for preparing magnetized steel, the method comprising:
[0006] Step S1) Powder filling: Fill the molding die with alloy powder containing magnetic metal;
[0007] Step S2) Orientation: Place an electromagnet on one side of the molding die with the first magnetic pole of the electromagnet facing the first side of the molding die. The electromagnet gives the alloy powder an orientation, so that the alloy powder has an easy magnetization direction along the magnetic field lines of the electromagnet.
[0008] Step S3) Pressing: After the alloy powder is oriented, it is pressed to obtain a sintering precursor. The sintering precursor has a preset magnetic focusing area on the first side of the electromagnet.
[0009] Step S4) Sintering: The sintering precursor is sintered to obtain the sintered body, and the sintered body has the same preset magnetic focusing region as the sintering precursor;
[0010] Step S5) Magnetization: The electromagnet is placed on the first side of the sintered body and the first magnetic pole of the electromagnet is facing the preset magnetic concentration area. The sintered body is magnetized by the electromagnet to form a magnetic steel. After magnetization, the preset magnetic concentration area of the sintered body forms the magnetic concentration area of the magnetic steel.
[0011] The average magnetic field strength of the magnetic focusing region of the magnetic steel is more than three times the average magnetic field strength of other regions on the surface where the magnetic focusing region is located.
[0012] Optionally, the alloy powder is neodymium iron boron alloy powder.
[0013] Optionally, in step S2, there are two electromagnets, which are located on the first side of the molding die and the second side opposite to the first side, respectively, and the first magnetic poles of the two electromagnets are respectively facing the first side and the second side of the molding die.
[0014] In step S3, the pressed sintering precursor has the preset magnetic focusing area on the first and second sides of the electromagnet, respectively.
[0015] In step S4, the sintered body has the same two preset magnetic focusing regions as the sintered body;
[0016] In step S5, the two electromagnets are placed on the first side and the second side of the sintered body, respectively, and the first magnetic poles of the two electromagnets are facing the two preset magnetic concentration zones, and magnetization is performed to obtain the magnetic steel with the two magnetic concentration zones.
[0017] Optionally, in step S2, there are two electromagnets located at the upper and lower ends of the first side of the molding die, with the first magnetic pole of the upper electromagnet facing the first side of the molding die and the second magnetic pole of the lower electromagnet facing the first side of the molding die.
[0018] In step S3, the pressed sintering precursor has two preset magnetic focusing areas on the upper and lower sides corresponding to the first side of the electromagnet.
[0019] In step S4, the sintered body has the same two preset magnetic focusing regions as the sintered body;
[0020] In step S5, the two electromagnets are placed at the upper and lower ends of the first side of the sintered body. The first magnetic pole of the upper electromagnet faces the first side of the molding mold, and the second magnetic pole of the lower electromagnet faces the first side of the molding mold. Magnetization is performed to obtain a magnetic steel with two magnetic focusing regions.
[0021] Optionally, in step S1, the molding die is a cuboid, and the upper surface of the molding die has two inwardly recessed grooves, which are symmetrically distributed about a vertical line passing through the center point of the molding die.
[0022] In step S2, there are two electromagnets, which are respectively inserted into the two grooves. Each groove has two oppositely arranged sidewalls. The two magnetic poles of each electromagnet are respectively facing the top of the two sidewalls of the corresponding groove, and the opposite magnetic poles of the two electromagnets have the same polarity.
[0023] In step S3, the pressed sintering precursor has two grooves and four sidewalls that are the same as the forming mold, and the sintering precursor has the preset magnetic focusing area at the top of the four sidewalls corresponding to the electromagnet.
[0024] In step S4, the sintered body has the same two grooves and four preset magnetic focusing areas as the sintered body;
[0025] In step S5, the two electromagnets are respectively placed in the two grooves of the sintered body, and the magnetic poles of the two electromagnets are facing the four preset magnetic concentration zones, and magnetization is performed to obtain the magnetic steel with the four magnetic concentration zones.
[0026] A second aspect of the present invention provides a magnetic steel with a magnetic concentration region on its surface and multiple different magnetization directions inside the magnetic steel, all of which converge in the magnetic concentration region. The average magnetic field strength of the magnetic concentration region is more than three times that of the average magnetic field strength of other areas on the surface where the magnetic concentration region is located.
[0027] A third aspect of the present invention provides a loudspeaker, including a vibration system and a magnetic circuit system for driving the vibration system to produce sound. The vibration system includes a diaphragm and a voice coil that drives the diaphragm to vibrate. The magnetic circuit system includes a magnet assembly, which includes a first magnetic part and a second magnetic part that forms a magnetic gap with the first magnetic part. The first magnetic part and / or the second magnetic part is a focusing magnet. The magnetic circuit system has a magnetic field concentration region in the magnetic gap. The focusing region of the focusing magnet corresponds to the magnetic gap to form the magnetic field concentration region. The average magnetic field strength of the magnetic field concentration region is more than three times that of the non-magnetic field concentration region in the magnetic gap. The voice coil is disposed in the magnetic field concentration region.
[0028] Optionally, the magnetic circuit system further includes a lower clamp fixed to the side of the magnet assembly away from the diaphragm.
[0029] Optionally, both the first magnetic part and the second magnetic part are the same magnetic steel, and the first magnetic part and the second magnetic part include sidewalls forming the magnetic gap, with the magnetic field concentration area located at the top of the sidewall or at the middle of the sidewall.
[0030] Optionally, the magnetic field concentration area is located at the top of the sidewall, the second magnetic part has a notch in the magnetic field concentration area, and the magnetic circuit system further includes a first magnetic conductive element disposed in the notch.
[0031] Optionally, the first magnetic part is the high-magnetic steel, the magnetization direction of the second magnetic part is parallel to the vibration direction of the speaker, and the magnetic circuit system further includes a first magnetic conductor attached to the surface of the second magnetic part, the first magnetic conductor being disposed corresponding to the magnetic field concentration area.
[0032] Optionally, the second magnetic part is the high-magnetic steel, the magnetization direction of the first magnetic part is parallel to the vibration direction of the speaker, and the magnetic circuit system further includes a second magnetic conductor attached to the surface of the first magnetic part, the second magnetic conductor being disposed corresponding to the magnetic field concentration area.
[0033] Optionally, both the first magnetic part and the second magnetic part are the same magnetic steel, and the first magnetic part and the second magnetic part include sidewalls forming the magnetic gap. The magnetic field concentration area is located at the top of the sidewalls, and the magnetic circuit system further includes a third magnetic conductor disposed at the bottom of the sidewalls.
[0034] Optionally, both the first magnetic part and the second magnetic part are the same magnetic steel, and the first magnetic part and the second magnetic part include sidewalls forming the magnetic gap. The magnetic field concentration area is located at the top of the sidewalls. The magnetic circuit system also includes an auxiliary magnet disposed at the bottom of the sidewalls, and the magnetization direction of the auxiliary magnet is perpendicular to the vibration direction of the speaker.
[0035] A fourth aspect of the present invention provides another loudspeaker, including a vibration system and a magnetic circuit system for driving the vibration system to produce sound. The vibration system includes a diaphragm and a voice coil that drives the diaphragm to vibrate. The magnetic circuit system includes a first portion and a second portion forming a magnetic gap with the first portion. The first portion and the second portion include sidewalls forming the magnetic gap. The magnetic circuit system further includes a third portion connecting the first portion and the second portion. The third portion is disposed at the bottom of the sidewalls. The first portion, the second portion, and the third portion are integrally formed into a single magnet. The single magnet is a concentrating magnet. The concentrating region of the concentrating magnet is located at the top of each sidewall. The magnetic circuit system has a magnetic field concentration region in the magnetic gap. The concentrating region forms the magnetic field concentration region corresponding to the magnetic gap. The average magnetic field strength of the magnetic field concentration region is more than three times that of the non-magnetic field concentration region in the magnetic gap. The voice coil is disposed in the magnetic field concentration region. Beneficial effects
[0036] Compared with related technologies, the loudspeaker provided by the present invention has different magnetization directions in different regions inside the magnet assembly, so that the magnetization directions converge in the magnetic field concentration area of the magnetic gap, thereby generating a magnetic focusing effect in the magnet assembly itself. This eliminates the need for a pole core and generates a stronger magnetic field in the magnetic field concentration area, improving the driving force of the voice coil and the response frequency of the diaphragm, increasing the sensitivity of the loudspeaker, reducing magnetic leakage, and facilitating the miniaturization of the loudspeaker. Attached Figure Description
[0037] Figure 1 is a schematic diagram of the existing method for preparing magnets;
[0038] Figure 2 is a flowchart of the preparation method of the polymagnetic steel provided by the present invention;
[0039] Figure 3 is a schematic diagram of the preparation method of the first type of polymagnetic steel provided by the present invention;
[0040] Figure 4 is a schematic diagram of the preparation method of the second type of polymagnetic steel provided by the present invention;
[0041] Figure 5 is a schematic diagram of the preparation method of the third type of polymagnetic steel provided by the present invention;
[0042] Figure 6 is a schematic diagram of the preparation method of the fourth type of polymagnetic steel provided by the present invention;
[0043] Figure 7 is a perspective view of the loudspeaker provided by the present invention;
[0044] Figure 8 is a cross-sectional view along line AA in Figure 7;
[0045] Figure 9 is an exploded three-dimensional view of the speaker in Figure 7;
[0046] Figure 10 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the first type of loudspeaker provided by the present invention;
[0047] Figure 11 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the second type of loudspeaker provided by the present invention;
[0048] Figure 12 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the third type of loudspeaker provided by the present invention;
[0049] Figure 13 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the fourth type of loudspeaker provided by the present invention;
[0050] Figure 14 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the fifth type of loudspeaker provided by the present invention;
[0051] Figure 15 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the sixth type of loudspeaker provided by the present invention;
[0052] Figure 16 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the seventh type of loudspeaker provided by the present invention;
[0053] Figure 17 is a cross-sectional schematic diagram of the magnetic circuit system and voice coil in the eighth type of loudspeaker provided by the present invention;
[0054] In the figure: loudspeaker 100, frame 11, vibration system 20, diaphragm 21, voice coil 22, frame 23, flexible circuit board 24, magnetic circuit system 30, magnet assembly 31, first magnetic part 32, second magnetic part 33, magnetic gap 34, magnetic field concentration area 341, lower clamping plate 35, first magnetic conductor 36, second magnetic conductor 37, third magnetic conductor 38, auxiliary magnet 39, integrated magnet 40. Embodiments of the present invention
[0055] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0056] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.
[0057] Traditional magnets use a uniform magnetic field with a single direction for orientation and magnetization. The magnet used in this invention, however, employs a curved magnetic field that converges towards a specific region. This specific magnetic field can be generated by an electromagnet. Depending on the type of magnet required, the magnetic field of a specific region of the electromagnet can be selected, or a magnetic field generated by a combination of multiple electromagnets can be used. Please refer to Figures 2 to 6, which illustrate the preparation and magnetization method of the magnet provided by this invention, including the following steps:
[0058] Step S1) Powder filling: The alloy raw material containing magnetic metal is cleaned and smelted to obtain an alloy. The alloy is then subjected to processes such as hydrogen crushing and air jet milling to obtain alloy powder. The alloy powder is then filled into a molding die.
[0059] Step S2) Orientation: Place an electromagnet on one side of the molding die with the first magnetic pole of the electromagnet facing the first side of the molding die. The electromagnet gives the alloy powder an orientation, so that the alloy powder has an easy magnetization direction along the magnetic field lines of the electromagnet.
[0060] Step S3) Pressing: After the alloy powder is oriented, it is placed in a forming press and pressed to obtain the sintering precursor. The sintering precursor has a preset magnetic focusing area on the first side of the electromagnet (marked by the dotted circle in the figure).
[0061] Step S4) Sintering: The sintering precursor is placed in a sintering furnace for sintering to obtain the sintered body. The sintered body has the same preset magnetic focusing area as the sintering precursor.
[0062] Step S5) Magnetization: Place the electromagnet on the first side of the sintered body and the first magnetic pole of the electromagnet is facing the preset magnetic concentration area. The sintered body is magnetized by the electromagnet to form a magnetic steel. After magnetization, the preset magnetic concentration area of the sintered body becomes the magnetic concentration area of the magnetic steel.
[0063] In the above steps, the first magnetic pole of the electromagnet can be S-pole and the second magnetic pole can be N-pole; or, the first magnetic pole of the electromagnet can be N-pole and the second magnetic pole can be S-pole.
[0064] The average magnetic field strength of the magnetic focusing region of the magnetic steel obtained through the above steps is more than three times the average magnetic field strength of other areas on the surface where the magnetic focusing region is located.
[0065] Preferably, the alloy powder is neodymium iron boron alloy powder, but it can also be other alloy powders containing magnetic metals.
[0066] Furthermore, depending on the actual needs, the orientation and magnetization of the focusing magnet can also be as shown in Figure 4. In step S2, there are two electromagnets, which are located on the first side of the forming mold and the second side opposite to the first side, respectively. The first magnetic poles of the two electromagnets are respectively facing the first side and the second side of the forming mold. In step S3, the pressed sintering prebody has a preset focusing magnetic area on the first side and the second side of the corresponding electromagnet. In step S4, the sintered body has two preset focusing magnetic areas, the same as the sintering prebody. In step S5, the two electromagnets are placed on the first side and the second side of the sintered body, respectively, and the first magnetic poles of the two electromagnets are facing the two preset focusing magnetic areas. Magnetization is performed to obtain a focusing magnet with two focusing magnetic areas.
[0067] Furthermore, depending on the actual needs, the orientation and magnetization of the focusing magnet can also be as shown in Figure 5. In step S2, there are two electromagnets located at the upper and lower ends of the first side of the forming mold. The first magnetic pole of the upper electromagnet faces the first side of the forming mold, and the second magnetic pole of the lower electromagnet faces the first side of the forming mold. In step S3, the pressed sintering prebody has two preset focusing magnetic regions on the upper and lower ends of the first side of the electromagnet. In step S4, the sintered body has the same two preset focusing magnetic regions as the sintering prebody. In step S5, the two electromagnets are placed at the upper and lower ends of the first side of the sintered body. The first magnetic pole of the upper electromagnet faces the first side of the forming mold, and the second magnetic pole of the lower electromagnet faces the first side of the forming mold. Magnetization is performed to obtain a focusing magnet with two focusing magnetic regions.
[0068] Furthermore, depending on the actual needs, the orientation and magnetization of the magnet can also be as shown in Figure 6. In step S1, the forming mold is a cuboid, and the upper surface of the forming mold has two inwardly recessed grooves. The two grooves are symmetrically distributed about a vertical line passing through the center point of the forming mold. In step S2, there are two electromagnets, which are respectively inserted into the two grooves. Each groove has two oppositely arranged sidewalls. The two magnetic poles of each electromagnet are respectively facing the top of the two sidewalls of the corresponding groove, and the opposite magnetic poles of the two electromagnets have the same polarity. In step S3, the sintered pre-body after pressing has the same two grooves and four sidewalls as the forming mold, and the top of the four sidewalls of the electromagnets in the sintered pre-body has a preset magnetizing area. In step S4, the sintered post-body has the same two grooves and four preset magnetizing areas as the sintered pre-body. In step S5, the two electromagnets are respectively placed in the two grooves of the sintered post-body, and the magnetic poles of the two electromagnets are facing the four preset magnetizing areas. Magnetization is performed to obtain a magnet with four magnetizing areas.
[0069] In addition, the present invention provides a magnetic steel with a magnetic concentration region on its surface and multiple different magnetization directions inside the magnetic steel. All magnetization directions converge in the magnetic concentration region, and the average magnetic field strength of the magnetic concentration region is more than three times the average magnetic field strength of other areas on the surface where the magnetic concentration region is located.
[0070] Please refer to Figures 7-16, which illustrate the first type of loudspeaker 100 provided by the present invention, including a frame 11, a vibration system 20 fixed to the frame 11, and a magnetic circuit system 30 for driving the vibration system 20 to produce sound. The vibration system 20 includes a diaphragm 21 fixed to the frame 11, a flexible circuit board 24 spaced apart from the diaphragm 21, a voice coil 22 electrically connected to the flexible circuit board 24 to drive the diaphragm 21 to vibrate, and a frame 23 fixed to the diaphragm 21 and supporting the voice coil 22.
[0071] The magnetic circuit system 30 includes a magnet assembly 31, which includes a first magnetic part 32 and a second magnetic part 33 forming a magnetic gap 34 with the first magnetic part 32. The first magnetic part 32 and / or the second magnetic part 33 are magnetizing magnets. The magnetic circuit system 30 has a magnetic field concentration region 341 in the magnetic gap 34. The magnetizing region of the magnetizing magnet forms a magnetic field concentration region 341 corresponding to the magnetic gap 34. The average magnetic field strength of the magnetic field concentration region 341 is more than three times that of the non-magnetic field concentration region in the magnetic gap 34. The voice coil 22 is disposed in the magnetic field concentration region 341.
[0072] In the initial state of the loudspeaker 100, the voice coil 22 is positioned in the magnetic field concentration region 341. At this time, the voice coil 22 can respond quickly. The first magnetic part 32 and / or the second magnetic part 33 are magnetized to become a concentrating magnet. The concentrating magnet has multiple different magnetization directions inside. All magnetization directions converge at the magnetic field concentration region 341, thereby generating a stronger magnetic field strength in the magnetic field concentration region 341. This magnetic field interacts with the energized voice coil 22, thereby increasing the driving force of the voice coil 22 to improve the response frequency of the diaphragm 21 and increase the sensitivity of the loudspeaker 100. At the same time, this structure can omit at least part of the pole core, which can reduce magnetic leakage and is conducive to the miniaturization of the loudspeaker 100.
[0073] Furthermore, please refer to Figures 10 to 14. The lines with arrows in the figures indicate the magnetization direction of the magnet assembly 31, which can be from the N pole to the S pole or from the S pole to the N pole. The magnetic circuit system 30 also includes a lower clamping plate 35 fixed to the side of the magnet assembly 31 away from the diaphragm 21.
[0074] Please refer to Figures 10 and 11, which are combined state diagrams of the magnetic circuit system 30 and voice coil 22 of the loudspeaker 100 provided by the present invention. The first magnetic part 32 and the second magnetic part 33 are both high-magnetic steel. The first magnetic part 32 and the second magnetic part 33 include sidewalls forming magnetic gaps 34. The magnetic field concentration area 341 is located at the top of the sidewall or at the middle of the sidewall. This structure can omit the pole core, increase the volume of the first magnetic part 32 and the second magnetic part 33, increase the magnetic field strength of the magnetic field concentration area 341, increase the driving force of the voice coil 22, and increase the sensitivity of the loudspeaker 100.
[0075] Optionally, as shown in Figure 12, the magnetic field concentration area 341 is located at the top of the sidewall, the second magnetic part 33 is provided with a notch in the magnetic field concentration area 341, and the magnetic circuit system 30 also includes a first magnetic conductor 36 disposed in the notch.
[0076] Optionally, as shown in Figure 13, the first magnetic part 32 is a magnetized steel, the magnetization direction of the second magnetic part 33 is parallel to the vibration direction of the speaker 100, and the magnetic circuit system 30 also includes a first magnetic conductor 36 attached to the surface of the second magnetic part 33, and the first magnetic conductor 36 is correspondingly disposed with the magnetic field concentration area 341.
[0077] Optionally, as shown in Figure 14, the second magnetic part 33 is a magnetized steel, the magnetization direction of the first magnetic part 32 is parallel to the vibration direction of the speaker 100, and the magnetic circuit system 30 also includes a second magnetic conductor 37 attached to the surface of the first magnetic part 32, the second magnetic conductor 37 being disposed corresponding to the magnetic field concentration area 341.
[0078] The speaker 100 provided by the present invention may omit the lower clamping plate 35. Please refer to Figures 15 and 16. The first magnetic part 32 and the second magnetic part 33 are both high-magnetic steel. The first magnetic part 32 and the second magnetic part 33 include sidewalls forming magnetic gaps 34. The magnetic field concentration area 341 is located at the top of the sidewalls. The magnetic circuit system 30 also includes a third magnetic conductor 38 disposed at the bottom of the sidewalls. The third magnetic conductor 38 connects the first magnetic part 32 and the second magnetic part, and can replace the lower clamping plate 35, further increasing the volume of the magnet assembly 31.
[0079] Alternatively, both the first magnetic part 32 and the second magnetic part 33 are high-magnetic steels. The first magnetic part 32 and the second magnetic part 33 include sidewalls forming magnetic gaps 34. The magnetic field concentration area 341 is located at the top of the sidewalls. The magnetic circuit system 30 also includes an auxiliary magnet 39 disposed at the bottom of the sidewalls. The magnetization direction of the auxiliary magnet 39 is perpendicular to the vibration direction of the speaker 100. The auxiliary magnet 39 connects the first magnetic part 32 and the second magnetic part 33 and can replace the lower clamping plate 35, further increasing the volume of the magnet assembly 31.
[0080] Furthermore, the present invention also provides a second type of loudspeaker 100. Unlike the first type of loudspeaker 100, the magnetic circuit system 30 of the second type of loudspeaker 100 adopts an integrated magnet 40 design. Specifically, please refer to Figure 17. The magnetic circuit system 30 includes a first part and a second part forming a magnetic gap 34 with the first part. The first part and the second part include sidewalls forming the magnetic gap 34. The magnetic circuit system 30 also includes a third part connecting the first part and the second part. The third part is disposed at the bottom of the sidewall. The first part, the second part and the third part are integrally formed into an integrated magnet 40. The integrated magnet 40 is a magnetizing magnet. The magnetizing region of the magnetizing magnet is located at the top of each sidewall. The magnetic circuit system 30 has a magnetic field concentration region 341 in the magnetic gap 34. The magnetizing region corresponds to the magnetic gap 34 to form the magnetic field concentration region 341. The average magnetic field strength of the magnetic field concentration region 341 is more than three times that of the non-magnetic field concentration region 341 in the magnetic gap 34. The voice coil 22 is disposed in the magnetic field concentration region 341. The magnetic circuit of this structure does not require any magnetic conductive material. The entire magnetic circuit is made of a large magnet with different magnetization directions inside, which can generate a magnetic focusing effect, thereby generating the highest horizontal magnetic field strength at the magnetic gap 34.
[0081] The magnetic circuit system 30 of the loudspeaker 100 adopts a magnetized steel with multiple magnetization directions inside. These magnetization directions converge in the magnetization area, thereby generating a magnetization effect in the magnet component 31 itself. This eliminates the need for a pole core and generates a stronger magnetic field in the magnetic field concentration area 341, thereby increasing the driving force of the voice coil 22 and the response frequency of the diaphragm 21, increasing the sensitivity of the loudspeaker 100, reducing magnetic leakage, and facilitating the miniaturization of the loudspeaker 100.
[0082] The above are merely embodiments of the present invention. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements all fall within the protection scope of the present invention.
Claims
1. A method for preparing a high-magnetic steel, characterized in that, Includes the following steps: Step S1) Powder filling: Fill the molding die with alloy powder containing magnetic metal; Step S2) Orientation: Place an electromagnet on one side of the molding die with the first magnetic pole of the electromagnet facing the first side of the molding die. The electromagnet gives the alloy powder an orientation, so that the alloy powder has an easy magnetization direction along the magnetic field lines of the electromagnet. Step S3) Pressing: After the alloy powder is oriented, it is pressed to obtain a sintering precursor. The sintering precursor has a preset magnetic focusing area on the first side of the electromagnet. Step S4) Sintering: The sintering precursor is sintered to obtain the sintered body, and the sintered body has the same preset magnetic focusing region as the sintering precursor; Step S5) Magnetization: The electromagnet is placed on the first side of the sintered body and the first magnetic pole of the electromagnet is facing the preset magnetic concentration area. The sintered body is magnetized by the electromagnet to form a magnetic steel. After magnetization, the preset magnetic concentration area of the sintered body forms the magnetic concentration area of the magnetic steel. The average magnetic field strength of the magnetic focusing region of the magnetic steel is more than three times the average magnetic field strength of other regions on the surface where the magnetic focusing region is located.
2. The method for preparing polymagnetic steel according to claim 1, characterized in that, The alloy powder is neodymium iron boron alloy powder.
3. The method for preparing polymagnetic steel according to claim 1, characterized in that, In step S2, there are two electromagnets, which are located on the first side of the molding mold and the second side opposite to the first side, respectively. The first magnetic poles of the two electromagnets are respectively facing the first side and the second side of the molding mold. In step S3, the pressed sintering precursor has the preset magnetic focusing area on the first and second sides of the electromagnet, respectively. In step S4, the sintered body has the same two preset magnetic focusing regions as the sintered body; In step S5, the two electromagnets are placed on the first side and the second side of the sintered body, respectively, and the first magnetic poles of the two electromagnets are facing the two preset magnetic concentration zones, and magnetization is performed to obtain the magnetic steel with the two magnetic concentration zones.
4. The method for preparing polymagnetic steel according to claim 1, characterized in that, In step S2, there are two electromagnets located at the upper and lower ends of the first side of the molding mold. The first magnetic pole of the upper electromagnet faces the first side of the molding mold, and the second magnetic pole of the lower electromagnet faces the first side of the molding mold. In step S3, the pressed sintering precursor has two preset magnetic focusing areas on the upper and lower sides corresponding to the first side of the electromagnet. In step S4, the sintered body has the same two preset magnetic focusing regions as the sintered body; In step S5, the two electromagnets are placed at the upper and lower ends of the first side of the sintered body. The first magnetic pole of the upper electromagnet faces the first side of the molding mold, and the second magnetic pole of the lower electromagnet faces the first side of the molding mold. Magnetization is performed to obtain a magnetic steel with two magnetic focusing regions.
5. The method for preparing polymagnetic steel according to claim 1, characterized in that, In step S1, the molding die is a cuboid, and the upper surface of the molding die has two inwardly recessed grooves, which are symmetrically distributed about a vertical line passing through the center point of the molding die. In step S2, there are two electromagnets, which are respectively inserted into the two grooves. Each groove has two oppositely arranged sidewalls. The two magnetic poles of each electromagnet are respectively facing the top of the two sidewalls of the corresponding groove, and the opposite magnetic poles of the two electromagnets have the same polarity. In step S3, the pressed sintering precursor has two grooves and four sidewalls that are the same as the forming mold, and the sintering precursor has the preset magnetic focusing area at the top of the four sidewalls corresponding to the electromagnet. In step S4, the sintered body has the same two grooves and four preset magnetic focusing areas as the sintered body; In step S5, the two electromagnets are respectively placed in the two grooves of the sintered body, and the magnetic poles of the two electromagnets are facing the four preset magnetic concentration zones, and magnetization is performed to obtain the magnetic steel with the four magnetic concentration zones.
6. A type of high-magnetic steel, characterized in that, The surface of the magnet has a magnetizing region, and the interior of the magnet has multiple different magnetization directions. All magnetization directions converge in the magnetizing region, and the average magnetic field strength of the magnetizing region is more than three times the average magnetic field strength of other areas on the surface where the magnetizing region is located.
7. A loudspeaker, comprising a vibration system and a magnetic circuit system for driving the vibration system to produce sound, the vibration system comprising a diaphragm and a voice coil for driving the diaphragm to vibrate; the magnetic circuit system comprising a magnet assembly, the magnet assembly comprising a first magnetic portion and a second magnetic portion forming a magnetic gap with the first magnetic portion, characterized in that, The first magnetic part and / or the second magnetic part are the magnetic steel as described in claim 6, the magnetic circuit system has a magnetic field concentration area in the magnetic gap, the magnetic concentration area of the magnetic steel corresponds to the magnetic gap to form the magnetic field concentration area, the average magnetic field strength of the magnetic field concentration area is more than three times that of the non-magnetic field concentration area in the magnetic gap, and the voice coil is disposed in the magnetic field concentration area.
8. The loudspeaker according to claim 7, characterized in that, The magnetic circuit system also includes a lower clamp plate fixed to the side of the magnet assembly away from the diaphragm.
9. The loudspeaker according to claim 8, characterized in that, Both the first magnetic part and the second magnetic part are the same magnetic steel, and the first magnetic part and the second magnetic part include sidewalls forming the magnetic gap. The magnetic field concentration area is located at the top of the sidewall or at the middle of the sidewall.
10. The loudspeaker according to claim 9, characterized in that, The magnetic field concentration area is located at the top of the sidewall, the second magnetic part has a notch in the magnetic field concentration area, and the magnetic circuit system also includes a first magnetic conductive element disposed in the notch.
11. The loudspeaker according to claim 8, characterized in that, The first magnetic part is the high-magnetic steel, the magnetization direction of the second magnetic part is parallel to the vibration direction of the speaker, and the magnetic circuit system further includes a first magnetic conductor attached to the surface of the second magnetic part, the first magnetic conductor being disposed corresponding to the magnetic field concentration area.
12. The loudspeaker according to claim 8, characterized in that, The second magnetic part is the magnetizing steel, the magnetization direction of the first magnetic part is parallel to the vibration direction of the speaker, and the magnetic circuit system further includes a second magnetic conductor attached to the surface of the first magnetic part, the second magnetic conductor being disposed corresponding to the magnetic field concentration area.
13. The loudspeaker according to claim 7, characterized in that, Both the first magnetic part and the second magnetic part are the same magnetic steel. The first magnetic part and the second magnetic part include sidewalls forming the magnetic gap. The magnetic field concentration area is located at the top of the sidewall. The magnetic circuit system also includes a third magnetic conductor disposed at the bottom of the sidewall.
14. The loudspeaker according to claim 7, characterized in that, Both the first magnetic part and the second magnetic part are the same magnetic steel. The first magnetic part and the second magnetic part include sidewalls forming the magnetic gap. The magnetic field concentration area is located at the top of the sidewall. The magnetic circuit system also includes an auxiliary magnet disposed at the bottom of the sidewall. The magnetization direction of the auxiliary magnet is perpendicular to the vibration direction of the speaker.
15. A loudspeaker, comprising a vibration system and a magnetic circuit system for driving the vibration system to produce sound, the vibration system comprising a diaphragm and a voice coil for driving the diaphragm to vibrate; the magnetic circuit system comprising a first portion and a second portion forming a magnetic gap with the first portion, characterized in that, The first part and the second part include sidewalls forming the magnetic gap. The magnetic circuit system further includes a third part connecting the first part and the second part. The third part is disposed at the bottom of the sidewall. The first part, the second part, and the third part are integrally formed into a single magnet. The single magnet is a magnetizing magnet as described in claim 6. The magnetizing region of the magnetizing magnet is located at the top of each sidewall. The magnetic circuit system has a magnetic field concentration region in the magnetic gap. The magnetizing region forms the magnetic field concentration region corresponding to the magnetic gap. The average magnetic field strength of the magnetic field concentration region is more than three times that of the non-magnetic field concentration region in the magnetic gap. The voice coil is disposed in the magnetic field concentration region.