Linear vibration motor and electronic device

Abstract

The application relates to the technical field of electronic equipment, and discloses a linear vibration motor and electronic equipment. The linear vibration motor comprises a shell, a stator module and a mover module, the shell comprises an upper shell and a lower shell; the stator module comprises a top coil assembly and a bottom coil assembly, the top coil assembly is fixed to the upper shell, and the bottom coil assembly is fixed to the lower shell; the mover module is located between the top coil assembly and the bottom coil assembly, the mover module comprises a counterweight, a first magnet, a second magnet and an elastic piece, the top of the counterweight is provided with a first groove, the bottom of the counterweight is provided with a second groove, and the first groove and the second groove are arranged at intervals; the first magnet is arranged in the first groove, the second magnet is arranged in the second groove, and the first magnet is parallel to the second magnet; and the two ends of the counterweight are connected with the inner wall of the shell through the elastic piece. The application can increase the pushing force on the mover module, increase the overall counterweight of the mover module, and make the motor have stronger vibration feeling.

Description

Technical Field

[0001] The present invention relates to the field of electronic equipment technology, and in particular to a linear vibration motor and electronic equipment. Background Technology

[0002] Linear vibration motors are commonly found in existing electronic devices such as smartphones, smartwatches, and wearable devices like VR / CR to enhance the user experience. A linear vibration motor mainly consists of a stator and a mover housed within a casing. The mover is connected to the casing by a pair of springs, while the stator is fixed to the casing and located outside the mover. The stator typically consists of coils, and the mover generally consists of magnets and a counterweight. During operation, alternating current flows through the coils, which are driven by the Lorentz force in the magnetic field generated by the magnets. Because the coils are fixed, the mover reciprocates linearly within the stator, thus generating vibration.

[0003] Current linear vibration motors have the following problems: 1) The magnets usually adopt a single magnet design. Single magnets have problems such as insufficient magnetic field strength and rapid magnetic field decay. Moreover, the magnetic field of a single magnet decays exponentially with distance. The coil needs to be in close contact with the magnet surface (spacing < 0.2mm) to obtain sufficient thrust; 2) The magnetic field gradient of a single magnet is weak, resulting in low position control accuracy (±0.2mm) and poor thrust-displacement linearity (thrust fluctuation > 20% when stroke > 0.3mm); 3) Existing movers usually adopt an encased design to carry the magnet, that is, the middle of the counterweight is hollowed out as a through hole to install the magnet. This structure leads to a decrease in the overall weight of the mover, which in turn leads to a decrease in motor vibration.

[0004] Therefore, there is an urgent need for a linear vibration motor and electronic device to solve the above-mentioned technical problems. Summary of the Invention

[0005] Based on the above, the purpose of this invention is to provide a linear vibration motor and electronic device that can increase the driving force on the moving part module and increase the overall counterweight of the moving part module, thereby making the motor vibrate more strongly.

[0006] To achieve this objective, the embodiments of the present invention adopt the following technical solutions: On one hand, embodiments of the present invention provide a linear vibration motor, comprising: The housing includes an upper shell and a lower shell, wherein the upper shell and the lower shell are connected to form an accommodating cavity; A stator module is disposed within the accommodating cavity. The stator module includes a top coil assembly and a bottom coil assembly. The top coil assembly is fixed to the upper shell, and the bottom coil assembly is fixed to the lower shell. A moving element module is disposed within the accommodating cavity and located between the top coil assembly and the bottom coil assembly. The moving element module includes a counterweight, a first magnet, a second magnet, and an elastic element. The top of the counterweight has a first groove, and the bottom of the counterweight has a second groove, with the first groove and the second groove spaced apart. The first magnet is disposed within the first groove, and the second magnet is disposed within the second groove, with the first magnet parallel to the second magnet. Both ends of the counterweight are connected to the inner wall of the housing via the elastic element.

[0007] In some possible implementations, both the first magnet and the second magnet are magnetized with two poles along the thickness direction, and the polarities of the two magnetic poles along the thickness direction are opposite; both the first magnet and the second magnet are magnetized with at least two poles along the length direction, and the magnetism of each magnetic pole along the length direction is alternately arranged sequentially; the magnetic poles of the first magnet along the length direction and the magnetic poles of the second magnet along the length direction are respectively center-aligned.

[0008] In some possible implementations, the top coil assembly includes at least one first coil, the two opposite long sides of which correspond one-to-one with two opposite magnetic poles on the first magnet; the bottom coil assembly includes at least one second coil, the two opposite long sides of which correspond one-to-one with two opposite magnetic poles on the second magnet; the number of the first coil and the second coil are equal and they are vertically aligned.

[0009] In some possible implementations, on the surfaces of the first magnet and the second magnet that are close to each other, the two magnetic poles that are aligned with each other have the same polarity; the current flowing through the first coil and the corresponding second coil are in opposite directions.

[0010] In some possible implementations, on the surfaces of the first magnet and the second magnet that are close to each other, the polarities of the two magnetic poles that are aligned with each other are opposite; and the current flowing through the first coil and the corresponding second coil is in the same direction.

[0011] In some possible implementations, the first magnet has six magnetic poles along its length, and the top coil assembly includes three first coils arranged sequentially along the length of the first magnet, with the two opposite long sides of each first coil corresponding one-to-one with two adjacent magnetic poles on the first magnet. The second magnet has six magnetic poles along its length. The bottom coil assembly includes three second coils arranged sequentially along the length of the second magnet. The two opposite long sides of each second coil correspond one-to-one with two adjacent magnetic poles on the second magnet.

[0012] In some possible implementations, the first magnet has three magnetic poles along its length: a left magnetic pole, a middle magnetic pole, and a right magnetic pole. The width of the middle magnetic pole is greater than the width of both the left and right magnetic poles. The top coil assembly includes two first coils arranged sequentially along the length of the first magnet. The two opposite long sides of the left first coil correspond to the left half of the left and middle magnetic poles on the first magnet, respectively. The two opposite long sides of the right first coil correspond to the right half of the middle and right magnetic poles on the first magnet, respectively. The second magnet has three magnetic poles along its length: a left magnetic pole, a middle magnetic pole, and a right magnetic pole. The width of the middle magnetic pole is greater than the width of both the left and right magnetic poles. The bottom coil assembly includes two second coils arranged sequentially along the length of the second magnet. The two opposite long sides of the left second coil correspond to the left half of the left and middle magnetic poles on the second magnet, respectively. The two opposite long sides of the right second coil correspond to the right half of the middle and right magnetic poles on the second magnet, respectively.

[0013] In some possible implementations, the first magnet has a trapezoidal cross-section along its length, and the second magnet also has a trapezoidal cross-section along its length, with the upper bases of the two trapezoids being far apart from each other and the lower bases being close to each other.

[0014] In some possible implementations, the depth of the first groove is adapted to the thickness of the first magnet, the depth of the second groove is adapted to the thickness of the second magnet, and the distance between the first groove and the second groove is greater than the depth of the first groove and also greater than the depth of the second groove.

[0015] On the other hand, embodiments of the present invention provide an electronic device including the linear vibration motor described in any of the above solutions.

[0016] The beneficial effects of this invention are: The linear vibration motor provided in this invention, by setting two parallel magnets and two coil assemblies, effectively increases the driving force on the mover module through the interaction between the first magnet and the top coil assembly, and the interaction between the second magnet and the bottom coil assembly, so that the coil does not need to be in close contact with the magnet surface to obtain sufficient thrust. Moreover, the dual magnet design can improve the thrust density of the mover module, optimize the magnetic field gradient, improve the position control accuracy and thrust-displacement linearity. By changing the original encasing design of the counterweight block in the mover module to a shallow groove design, a first groove is set on the top of the counterweight block, and a second groove is set at the bottom of the counterweight block, spaced apart from the first groove. The first magnet is installed in the first groove, and the second magnet is installed in the second groove. This effectively increases the overall counterweight of the mover module, making the vibration of the linear vibration motor stronger. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the linear vibration motor provided in an embodiment of the present invention; Figure 2 This is an exploded view of the linear vibration motor provided in an embodiment of the present invention; Figure 3 This is a cross-sectional view of the counterweight block, the first magnet, and the second magnet provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the counterweight block, the first magnet, and the second magnet provided in an embodiment of the present invention; Figure 5 This is an exploded view of the counterweight block and the first magnet and the second magnet at a first angle according to an embodiment of the present invention; Figure 6 This is a second-angle exploded view of the counterweight block, the first magnet, and the second magnet provided in an embodiment of the present invention; Figure 7 This is a force analysis diagram of a first magnet, a second magnet, a first coil, and a second coil provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the counterweight block, the first magnet, and the second magnet provided in another embodiment of the present invention; Figure 9 This is an exploded view of the counterweight block and the first magnet and the second magnet at a first angle provided in another embodiment of the present invention; Figure 10 This is a second exploded view of the counterweight block, the first magnet, and the second magnet provided in another embodiment of the present invention; Figure 11 This is a schematic diagram of the structure of the counterweight, the first magnet, and the second magnet provided in another embodiment of the present invention; Figure 12 This is a first-angle exploded view of the counterweight block, the first magnet, and the second magnet provided in another embodiment of the present invention; Figure 13 This is a second exploded view of the counterweight block, the first magnet, and the second magnet provided in another embodiment of the present invention; Figure 14 This is another embodiment of the present invention, which provides a force analysis diagram of the first magnet, the second magnet, the first coil, and the second coil.

[0018] In the picture: 1. Housing; 11. Upper housing; 12. Lower housing; 21. Top coil assembly; 211. First coil; 22. Bottom coil assembly; 221. Second coil; 31. Counterweight; 311. First groove; 312. Second groove; 32. First magnet; 33. Second magnet; 341. First spring; 342. Second spring; 41. Upper yoke; 42. Lower yoke; 5. Circuit board; 61. Top sealing film; 62. Bottom sealing film; 7. Bracket; 71. Locking hole. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] In the description of this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] This invention provides a linear vibration motor that can be applied to electronic devices such as smartphones, smartwatches, game consoles, and VR / CR systems.

[0024] like Figures 1 to 14 As shown, the linear vibration motor provided in this embodiment includes a housing 1, a stator module, and a rotor module. The housing 1 includes an upper shell 11 and a lower shell 12, which can be connected by bonding, screwing, snap-fitting, etc., and after assembly, the upper shell 11 and the lower shell 12 enclose a receiving cavity. Optionally, in this embodiment, the upper shell 11 includes a horizontally arranged top wall and four side walls extending vertically from the top wall to the lower shell 12, and the lower shell 12 includes a flat bottom wall. In this embodiment, the upper shell 11 and the lower shell 12 can be made of stainless steel, preferably SUS444-1 / 4H or a similar material, to ensure the structural strength of the housing 1, thereby providing reliable protection for the motor product. The stator module is disposed in the receiving cavity of the housing 1, and the stator module includes a top coil assembly 21 and a bottom coil assembly 22. The top coil assembly 21 is fixed inside the upper shell 11, and the bottom coil assembly 22 is fixed inside the lower shell 12. In this embodiment, the top coil assembly 21 includes at least one first coil 211, and the bottom coil assembly 22 includes at least one second coil 221. The number of first coils 211 and second coils 221 are equal and they are vertically aligned. The linear vibration motor also includes a circuit board 5, which is partially disposed within the accommodating cavity and partially disposed outside the accommodating cavity. The top coil assembly 21 and the bottom coil assembly 22 are respectively connected to external circuitry via the circuit board 5. Optionally, the circuit board 5 in this embodiment is a flexible circuit board. The moving part module is disposed within the accommodating cavity and located between the top coil assembly 21 and the bottom coil assembly 22. The moving part module includes a counterweight 31, a first magnet 32, a second magnet 33, and an elastic element. The top of the counterweight 31 is provided with a first groove 311, and the bottom of the counterweight 31 is provided with a second groove 312. The first groove 311 and the second groove 312 are spaced apart. The first magnet 32 ​​is disposed in the first groove 311, and the second magnet 33 is disposed in the second groove 312, with the first magnet 32 ​​parallel to the second magnet 33. The two ends of the counterweight 31 are connected to the inner wall of the housing 1 through the elastic element.

[0025] During operation, alternating current is supplied to the top coil assembly 21 and the bottom coil assembly 22 respectively. The top coil assembly 21 is driven by the Lorentz force in the magnetic field generated by the first magnet 32, and the bottom coil assembly 22 is driven by the Lorentz force in the magnetic field generated by the second magnet 33. Since the top coil assembly 21 and the bottom coil assembly 22 are fixed inside the housing 1, they cannot move. However, due to the action-reaction relationship, the first magnet 32 ​​is subjected to a pushing force in the opposite direction to the Lorentz force on the top coil assembly 21, and the second magnet 33 is subjected to a pushing force in the opposite direction to the Lorentz force on the bottom coil assembly 22. In this embodiment, by adjusting the current direction in the top coil assembly 21 and the bottom coil assembly 22, the pushing force on the first magnet 32 ​​and the pushing force on the second magnet 33 can be made to be in the same direction. Therefore, under the combined action of the two pushing forces, the entire moving module makes linear reciprocating motion within the housing 1, thereby generating vibration.

[0026] The linear vibration motor provided in this embodiment of the invention is equipped with two parallel magnets and two coil assemblies. Through the interaction between the first magnet 32 ​​and the top coil assembly 21, and the interaction between the second magnet 33 and the bottom coil assembly 22, the driving force on the mover module is effectively increased, allowing the coils to obtain sufficient thrust without being in close contact with the magnet surface. Moreover, the dual-magnet design can improve the thrust density of the mover module, optimize the magnetic field gradient, and improve the position control accuracy and thrust-displacement linearity. By changing the original encasing design of the counterweight block 31 in the mover module to a shallow groove design, a first groove 311 is provided on the top of the counterweight block 31, and a second groove 312 spaced apart from the first groove 311 is provided on the bottom of the counterweight block 31. The first magnet 32 ​​is installed in the first groove 311, and the second magnet 33 is installed in the second groove 312. This effectively increases the overall weight of the mover module, avoiding the problem of weight reduction of the mover module caused by the hollow center of the counterweight block 31 in the prior art, and effectively improving the vibration feel of the linear vibration motor.

[0027] Optionally, in this embodiment, both the first magnet 32 ​​and the second magnet 33 are made of neodymium iron boron (NdFeB), which can generate a strong magnetic field, enhancing the driving force on the mover module and enabling the linear motor to have higher acceleration start-stop and a stronger, shorter vibration. Furthermore, NdFeB has good anti-demagnetization capabilities and a low long-term magnetic decay rate, which can improve the motor's service life. Optionally, in this embodiment, the counterweight 31 is made of tungsten-nickel-iron alloy. Using tungsten-nickel-iron alloy as the counterweight 31 can provide sufficient weight within a limited space, improving the mechanical performance, service life, and vibration experience of the linear vibration motor.

[0028] Optionally, the first magnet 32 ​​is fixed in the first groove 311 by adhesive bonding, and the second magnet 33 is fixed in the second groove 312 by adhesive bonding. Further, the depth of the first groove 311 is adapted to the thickness of the first magnet 32 ​​(for example, they can be approximately equal), and the depth of the second groove 312 is adapted to the thickness of the second magnet 33 (for example, they can be approximately equal). This ensures the reliability of the installation of the first magnet 32 ​​and the second magnet 33, while avoiding excessive occupation of the counterweight block 31 space by the first groove 311 and the second groove 312. Optionally, in this embodiment, the distance between the bottom of the first groove 311 and the bottom of the second groove 312 (i.e., the thickness of the remaining part of the counterweight block 31 after removing the first groove 311 and the second groove 312) is greater than the depth of the first groove 311 and also greater than the depth of the second groove 312. This setting ensures that the remaining part of the counterweight block 31 has sufficient weight, thereby giving the motor a stronger vibration.

[0029] In this embodiment, the first magnet 32 ​​and the second magnet 33 are both planar multipole magnets with a single structure, and the first magnet 32 ​​is placed parallel to the second magnet 33. This helps to reduce the thickness of the first magnet 32 ​​and the second magnet 33, thereby reducing the depth of the first groove 311 and the second groove 312, ensuring the overall weight of the moving part module; and the integral structure is convenient for assembly, which helps to improve assembly efficiency.

[0030] Furthermore, in this embodiment, the cross-section of the first magnet 32 ​​along its length is trapezoidal, and the cross-section of the second magnet 33 along its length is also trapezoidal, with the upper bases of the two trapezoids far apart and the lower bases close together. The hypotenuse of the trapezoidal magnets causes the magnetic field to gradually transition from the center of the magnetic pole to the edge, resulting in a smoother magnetic field gradient and thus a more uniform change in the Lorentz force with displacement. By designing the first magnet 32 ​​and the second magnet 33 as trapezoidal structures, this embodiment can reduce edge magnetic leakage, reduce harmonics and thrust fluctuations, and optimize tactile and auditory comfort. Compared with linear vibration motors in the prior art, the linear vibration motor provided in this embodiment has more concentrated main vibration energy, thrust fluctuations of <8% (close to linear) within ±0.5mm of the stroke, a smaller proportion of 3rd and 5th harmonics, reduced vibration spikes and noise, a crisper tactile feel, and a more comfortable auditory experience.

[0031] Optionally, the first magnet 32 ​​and the second magnet 33 have the same structure and magnetization method. Both the first magnet 32 ​​and the second magnet 33 are magnetized with two poles along the thickness direction, and the polarities of the two magnetic poles along the thickness direction are opposite (e.g., N pole and S pole respectively); both the first magnet 32 ​​and the second magnet 33 are magnetized with at least two poles along the length direction, and the magnetism of each magnetic pole along the length direction is alternately arranged sequentially (e.g., N pole, S pole, N pole, S pole respectively); the magnetic poles of the first magnet 32 ​​along the length direction and the magnetic poles of the second magnet 33 along the length direction are respectively center-aligned.

[0032] Optionally, in this embodiment, both the first coil 211 and the second coil 221 are racetrack-shaped, each having two opposite long sides. After energization, the current flowing through the two opposite long sides of the same coil flows in opposite directions. Specifically, the two opposite long sides of the first coil 211 correspond one-to-one with the two opposite magnetic poles on the first magnet 32, thus ensuring that the Lorentz force on the two long sides of the first coil 211 is in the same direction, thereby ensuring a reliable driving force for the mover module. Similarly, the two opposite long sides of the second coil 221 correspond one-to-one with the two opposite magnetic poles on the second magnet 33, thus ensuring that the Lorentz force on the two long sides of the second coil 221 is in the same direction, thereby ensuring a reliable driving force for the mover module. Optionally, in this embodiment, both the first coil 211 and the second coil 221 are integrally wound, with approximately 200 turns, and the coil can be adjusted and customized according to actual needs. Furthermore, both the first coil 211 and the second coil 221 are made of pure copper, and a self-adhesive layer and an insulating layer are added to their surfaces. Preferably, the copper content in the materials of the first coil 211 and the second coil 221 is ≥99.95% to reduce energy loss due to internal resistance.

[0033] In some embodiments, on the surfaces of the first magnet 32 ​​and the second magnet 33 that are close to each other, the polarities of the two magnetic poles that are aligned with each other are the same (i.e., SS opposite, NN opposite); the current flowing through the first coil 211 and the corresponding second coil 221 below it is in opposite directions. For example, as... Figures 4-7 As shown, the first magnet 32 ​​has two magnetic poles along its thickness direction, and six magnetic poles along its length direction on both its upper and lower surfaces. The polarities of the six magnetic poles on the upper surface of the first magnet 32 ​​are N, S, N, S, N, S, and the polarities of the six magnetic poles on the lower surface of the first magnet 32 ​​are S, N, S, N, S, N, S, N, respectively. The top coil assembly 21 includes three first coils 211 arranged sequentially along the length direction of the first magnet 32. The two opposite long sides of each first coil 211 correspond one-to-one with two adjacent magnetic poles on the first magnet 32, and the current flowing through the three first coils 211 is in the same direction. (Continue to refer to...) Figures 4-7 The second magnet 33 has two magnetic poles along its thickness direction, and six magnetic poles are provided on its upper and lower surfaces along its length direction. The polarities of the six magnetic poles on the upper surface of the first magnet 32 ​​are S, N, S, N, S, N, and the polarities of the six magnetic poles on the lower surface of the first magnet 32 ​​are N, S, N, S, N, S, and S, respectively. The bottom coil assembly 22 includes three second coils 221 arranged sequentially along the length direction of the second magnet 33. The two opposite long sides of each second coil 221 correspond one-to-one with the two adjacent magnetic poles on the second magnet 33. The current flowing through the three second coils 221 is in the same direction and opposite to the current flowing through the first coil 211.

[0034] like Figure 7 As shown, the first magnet 32, the second magnet 33, the first coil 211, and the second coil 221 are taken out for principle explanation. Taking any pair of the first coil 211 and the second coil 221, which are positioned vertically opposite each other, as an example, the first coil 211 receives alternating current from the outside. The current flows along the winding direction of the first coil 211. At a certain moment, the direction of the current in the first coil 211 is as shown in the figure. The current direction of the left loop is perpendicular to the plane of the figure and inwards, while the current direction of the right loop is perpendicular to the plane of the figure and outwards. The figure simply illustrates the direction of the magnetic field lines at the position of each loop. According to the left-hand rule, the magnetic force on the left loop is F1, directed to the right, and the magnetic force on the right loop is F2. Both are directed to the right and of the same magnitude. Therefore, the magnetic force on the entire first coil 211 is directed to the right. However, since the first coil 211 is fixed inside the upper shell 11, it cannot move. But due to the action-reaction relationship, the first magnet 32 ​​is subjected to F1' and F2' forces, which are opposite in direction and equal in magnitude to F1 and F2, respectively. Simultaneously, the second coil 221 receives alternating current from the outside, and the current flows along the winding direction of the second coil 221. At a certain moment, the first... The current direction in the second coil 221 is shown in the figure. The current direction in the left loop is perpendicular to the plane of the figure and outwards, while the current direction in the right loop is perpendicular to the plane of the figure and inwards. The figure simply illustrates the direction of the magnetic field lines at each loop position. According to the left-hand rule, the magnetic force on the left loop is F3, directed to the right, and the magnetic force on the right loop is F4, also directed to the right, and both are of the same magnitude. Therefore, the direction of the magnetic force on the entire second coil 221 is to the right. However, since the second coil 221 itself is fixed inside the lower shell 12, the first coil 2... While magnet 11 cannot move, due to the action-reaction relationship, the second magnet 33 is subjected to forces F3' and F4', which are opposite in direction and equal in magnitude to F3 and F4, respectively. Since the first magnet 32, the second magnet 33, and the counterweight 31 are suspended together within the accommodating space, and the elastic deformation direction of the elastic element is left-right of the housing 1, the first magnet 32, the second magnet 33, and the counterweight 31 move to the left under the influence of the magnetic field force (as indicated by the arrows F1', F2', F3', and F4' in the diagram). If the current direction changes, the first magnet 32, the second magnet 33, and the counterweight 31 move to the right, thus forming a reciprocating motion from left to right, thereby causing the motor to vibrate.

[0035] In other embodiments, such as Figures 8-10 As shown, the widths of the six magnetic poles arranged along the length direction on the first magnet 32 ​​and the second magnet 33 may not be exactly the same. For example, the two middle magnetic poles may be wider, while the four poles on the sides may be narrower. The working principle is similar to... Figures 4-7 The structure shown is the same, and will not be described again in this invention.

[0036] In other embodiments, on the surfaces of the first magnet 32 ​​and the second magnet 33 that are close to each other, the polarities of the two magnetic poles aligned with each other are opposite (i.e., SN opposite, NS opposite); the current flowing through the first coil 211 and the corresponding second coil 221 below it is in the same direction. With this configuration, the interaction between the first magnet 32 ​​and the second magnet 33 causes the magnetic fields to superimpose, strengthening the magnetic field and forming a strong vertical field, which can reach 1.5 to 2 times that of a single magnet; simultaneously, by superimposing the magnetic fields, high thrust density, rapid response, and precise control (up to ±0.05mm) can be achieved, increasing the thrust density by 2 to 3 times; and further optimizing the magnetic field gradient, improving the thrust-displacement linearity. For example, as... Figures 11-14 As shown, the first magnet 32 ​​has two magnetic poles along its thickness direction, and three magnetic poles along its length direction on both its upper and lower surfaces, namely a left magnetic pole, a middle magnetic pole, and a right magnetic pole. The width of the middle magnetic pole is greater than the width of both the left and right magnetic poles. The polarities of the three magnetic poles on the upper surface of the first magnet 32 ​​are N, S, and N, respectively, and the polarities of the three magnetic poles on the lower surface of the first magnet 32 ​​are S, N, and S, respectively. The top coil assembly 21 includes two first coils 211 arranged sequentially along the length direction of the first magnet 32. The two opposite long sides of the left first coil 211 correspond to the left half of the left magnetic pole and the left half of the middle magnetic pole on the first magnet 32, respectively. The two opposite long sides of the right first coil 211 correspond to the right half of the middle magnetic pole and the right magnetic pole on the first magnet 32, respectively. The current flowing through the two first coils 211 is in opposite directions. Preferably, in this embodiment, the left and right magnetic poles of the first magnet 32 ​​have the same width, and the width of the middle magnetic pole is twice the width of the left (or right) magnetic pole. (Continue to refer to...) Figures 11-14 The second magnet 33 has two magnetic poles along its thickness direction, and three magnetic poles along its length direction on both its upper and lower surfaces, namely a left magnetic pole, a middle magnetic pole, and a right magnetic pole. The width of the middle magnetic pole is greater than the width of both the left and right magnetic poles. The polarities of the three magnetic poles on the upper surface of the second magnet 33 are N, S, and N, respectively, and the polarities of the three magnetic poles on the lower surface of the first magnet 32 ​​are S, N, and S, respectively. The bottom coil assembly 22 includes two second coils 221 arranged sequentially along the length direction of the second magnet 33. The two opposite long sides of the left second coil 221 correspond to the left half of the left magnetic pole and the left half of the middle magnetic pole on the second magnet 33, respectively. The two opposite long sides of the right second coil 221 correspond to the right half of the middle magnetic pole and the right magnetic pole on the second magnet 33, respectively. The current flowing through the two second coils 221 is in opposite directions, and the current flowing through each second coil 221 and the corresponding first coil 211 above it is in the same direction.

[0037] like Figure 14As shown, the first magnet 32, the second magnet 33, the first coil 211, and the second coil 221 are taken out for principle explanation. Taking the first coil 211 and the second coil 221 located on the left as examples, the first coil 211 receives alternating current from the outside. The current flows along the winding direction of the first coil 211. At a certain moment, the current direction in the first coil 211 is as shown in the figure. The current direction of the left loop is perpendicular to the plane of the figure and inward, and the current direction of the right loop is perpendicular to the plane of the figure and outward. The figure simply illustrates the direction of the magnetic field lines at the position of each loop. According to the left-hand rule, the magnetic force on the left loop is F1, directed to the right, and the magnetic force on the right loop is F2. Both are directed to the right and of the same magnitude. Therefore, the magnetic force on the entire first coil 211 is directed to the right. However, since the first coil 211 is fixed inside the upper shell 11, it cannot move. But due to the action-reaction relationship, the first magnet 32 ​​is subjected to F1' and F2' forces, which are opposite in direction and equal in magnitude to F1 and F2, respectively. Simultaneously, the second coil 221 receives alternating current from the outside, and the current flows along the winding direction of the second coil 221. At a certain moment, the first... The current direction in the second coil 221 is shown in the figure. The current direction in the left loop is perpendicular to the plane of the figure and inwards, while the current direction in the right loop is perpendicular to the plane of the figure and outwards. The figure simply illustrates the direction of the magnetic field lines at each loop position. According to the left-hand rule, the magnetic force on the left loop is F3, directed to the right, and the magnetic force on the right loop is F4, also directed to the right, and both are of the same magnitude. Therefore, the direction of the magnetic force on the entire second coil 221 is to the right. However, since the second coil 221 itself is fixed inside the lower shell 12, the first coil 2... While magnet 11 cannot move, due to the action-reaction relationship, the second magnet 33 is subjected to forces F3' and F4', which are opposite in direction and equal in magnitude to F3 and F4, respectively. Since the first magnet 32, the second magnet 33, and the counterweight 31 are suspended together within the accommodating space, and the elastic deformation direction of the elastic element is left-right of the housing 1, the first magnet 32, the second magnet 33, and the counterweight 31 move to the left under the influence of the magnetic field force (as indicated by the arrows F1', F2', F3', and F4' in the diagram). If the current direction changes, the first magnet 32, the second magnet 33, and the counterweight 31 move to the right, thus forming a reciprocating motion from left to right, thereby causing the motor to vibrate.

[0038] Optionally, the elastic element in this embodiment includes a first spring piece 341 and a second spring piece 342. The first spring piece 341 is connected between one end of the counterweight 31 and one end of the housing 1, and the second spring piece 342 is connected between the other end of the counterweight 31 and the other end of the housing 1. Specifically, both the first spring piece 341 and the second spring piece 342 can be V-shaped or U-shaped spring pieces. The two free ends of the spring pieces are fixedly connected to the housing 1 and the counterweight 31, respectively, and the bent portions of the two spring pieces face both sides of the housing 1 along the width direction. Optionally, the first spring piece 341 and the second spring piece 342 are made of SUS301 stainless steel.

[0039] Optionally, in this embodiment, an upper magnetic yoke 41 is provided between the top coil assembly 21 and the upper shell 11, and a lower magnetic yoke 42 is provided between the bottom coil assembly 22 and the lower shell 12. Both the upper magnetic yoke 41 and the lower magnetic yoke 42 are made of silicon steel sheets and are used to guide, constrain, and enhance the magnetic field, thereby increasing the thrust density, reducing magnetic leakage, and improving linearity.

[0040] Optionally, a top sealing film 61 is provided on the top of the upper shell 11, and a bottom sealing film 62 is provided on the bottom of the lower shell 12, for sealing the linear vibration motor. The top sealing film 61 and the bottom sealing film 62 can be made of high molecular polymer material, preferably waterproof PET+PSA, which has the characteristics of high strength, good adhesion, good sealing performance, and long service life; and the top sealing film 61 and the bottom sealing film 62 are self-adhesive and can be directly attached to the upper shell 11 and the lower shell 12, which is simple to assemble and has a reliable seal.

[0041] Furthermore, the housing 1 is also provided with several brackets 7, each bracket having a locking hole 71 for fixing to an external structure with screws. For example, this embodiment provides three brackets 7, two of which are connected to both sides of the housing 1 along its length, and the third bracket 7 is connected to one side of the housing 1 along its width. This allows the linear vibration motor to be securely connected to electronic devices such as mobile phones and watches. Optionally, the brackets 7 are made of stainless steel, preferably SUS301-1 / 2H or a similar material, to ensure high strength and good support capacity.

[0042] This embodiment also provides an electronic device, including the linear vibration motor from any of the above-described solutions. Specifically, the electronic device can be a smartphone, smartwatch, game console, VR / CR, or other similar products. By employing the aforementioned linear vibration motor, the electronic device of this embodiment can increase the driving force on the moving part module and increase the overall counterweight of the moving part module, thereby making the vibration of the electronic device stronger.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A linear vibration motor, characterized in that, include: The housing includes an upper shell and a lower shell, wherein the upper shell and the lower shell are connected to form an accommodating cavity; A stator module is disposed within the accommodating cavity. The stator module includes a top coil assembly and a bottom coil assembly. The top coil assembly is fixed to the upper shell, and the bottom coil assembly is fixed to the lower shell. A moving element module is disposed within the accommodating cavity and located between the top coil assembly and the bottom coil assembly. The moving element module includes a counterweight, a first magnet, a second magnet, and an elastic element. The top of the counterweight has a first groove, and the bottom of the counterweight has a second groove, with the first groove and the second groove spaced apart. The first magnet is disposed within the first groove, and the second magnet is disposed within the second groove, with the first magnet parallel to the second magnet. Both ends of the counterweight are connected to the inner wall of the housing through the elastic element.

2. The linear vibration motor according to claim 1, characterized in that, Both the first magnet and the second magnet are magnetized with two poles along the thickness direction, and the polarities of the two magnetic poles along the thickness direction are opposite; both the first magnet and the second magnet are magnetized with at least two poles along the length direction, and the magnetism of each magnetic pole along the length direction is alternately arranged; the magnetic poles of the first magnet along the length direction and the magnetic poles of the second magnet along the length direction are respectively aligned at their centers.

3. The linear vibration motor according to claim 2, characterized in that, The top coil assembly includes at least one first coil, the two opposite long sides of which correspond one-to-one with the two opposite magnetic poles on the first magnet; the bottom coil assembly includes at least one second coil, the two opposite long sides of which correspond one-to-one with the two opposite magnetic poles on the second magnet; the number of the first coil and the second coil are equal and they are vertically aligned.

4. The linear vibration motor according to claim 3, characterized in that, On the surfaces of the first magnet and the second magnet that are close to each other, the polarities of the two magnetic poles that are aligned with each other are the same; the current flowing through the first coil and the corresponding second coil are in opposite directions.

5. The linear vibration motor according to claim 3, characterized in that, On the surfaces of the first magnet and the second magnet that are close to each other, the polarities of the two magnetic poles that are aligned with each other are opposite; the current flowing through the first coil and the corresponding second coil is in the same direction.

6. The linear vibration motor according to claim 4 or 5, characterized in that, The first magnet has six magnetic poles along its length. The top coil assembly includes three first coils arranged sequentially along the length of the first magnet. The two opposite long sides of each first coil correspond one-to-one with two adjacent magnetic poles on the first magnet. The second magnet has six magnetic poles along its length. The bottom coil assembly includes three second coils arranged sequentially along the length of the second magnet. The two opposite long sides of each second coil correspond one-to-one with two adjacent magnetic poles on the second magnet.

7. The linear vibration motor according to claim 4 or 5, characterized in that, The first magnet has three magnetic poles along its length: a left magnetic pole, a middle magnetic pole, and a right magnetic pole. The width of the middle magnetic pole is greater than the width of both the left and right magnetic poles. The top coil assembly includes two first coils arranged sequentially along the length of the first magnet. The two opposite long sides of the left first coil correspond to the left half of the left and middle magnetic poles on the first magnet, respectively. The two opposite long sides of the right first coil correspond to the right half of the middle and right magnetic poles on the first magnet, respectively. The second magnet has three magnetic poles along its length: a left magnetic pole, a middle magnetic pole, and a right magnetic pole. The width of the middle magnetic pole is greater than the width of both the left and right magnetic poles. The bottom coil assembly includes two second coils arranged sequentially along the length of the second magnet. The two opposite long sides of the left second coil correspond to the left half of the left and middle magnetic poles on the second magnet, respectively. The two opposite long sides of the right second coil correspond to the right half of the middle and right magnetic poles on the second magnet, respectively.

8. The linear vibration motor according to any one of claims 1-5, characterized in that, The first magnet has a trapezoidal cross-section along its length, and the second magnet also has a trapezoidal cross-section along its length, with the upper bases of the two trapezoids being far apart from each other and the lower bases being close to each other.

9. The linear vibration motor according to any one of claims 1-5, characterized in that, The depth of the first groove is adapted to the thickness of the first magnet, the depth of the second groove is adapted to the thickness of the second magnet, and the distance between the first groove and the second groove is greater than the depth of the first groove and also greater than the depth of the second groove.

10. An electronic device, characterized in that, Includes the linear vibration motor according to any one of claims 1-9.

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