Linear motor and electronic device

Abstract

The present invention relates to the technical field of linear motors. Disclosed are a linear motor and an electronic device. The linear motor comprises a housing having an accommodating space, and a vibrator assembly, a stator assembly and an elastic member which are arranged in the accommodating space; the vibrator assembly comprises a counterweight block provided with a mounting cavity, and a magnetic circuit structure fixed in the mounting cavity; the elastic member is connected to the housing and the counterweight block so as to suspend the vibrator assembly in the accommodating space; the stator assembly is fixedly connected to the housing, and is at least partially accommodated in the mounting cavity; the mounting cavity has two first cavity walls arranged opposite to each other in a direction perpendicular to the vibration direction of the vibrator assembly; the magnetic circuit structure comprises two magnetic steel assemblies respectively arranged on the two first cavity walls; each magnetic steel assembly comprises a central magnetic steel and two side magnetic steels respectively arranged on two sides of the central magnetic steel; a magnetic conductive plate is arranged between the central magnetic steel and the corresponding first cavity wall; and the side magnetic steels are fixedly connected to the corresponding first cavity wall. The technical solution provided by the present invention improves the efficiency of the linear motor.

Description

Linear motors and electronic devices Technical Field

[0001] This invention relates to the field of linear motor technology, and particularly to a linear motor and electronic device. Background Technology

[0002] In applications such as VR (Virtual Reality), AR (Augmented Reality), mobile phones, and tablets, linear motors are typically used as their vibration feedback units.

[0003] A linear motor is a device that converts electrical energy into mechanical energy using the principle of electromagnetic force generation. Generally, the structure of a linear motor includes an oscillator assembly suspended in a housing and a stator assembly fixed in the housing. The oscillator assembly includes a counterweight and a magnetic circuit structure fixed in a mounting cavity of the counterweight. At least part of the stator assembly is housed in the mounting cavity.

[0004] Currently, due to unreasonable magnetic circuit design or manufacturing defects, the magnetic field lines in linear motors may not be completely enclosed inside the magnetic circuit, and some magnetic field lines may leak to the outside of the magnetic circuit, resulting in magnetic leakage. Magnetic leakage will affect the operating efficiency of the linear motor. Summary of the Invention

[0005] The main objective of this invention is to provide a linear motor and electronic device that aims to improve the efficiency of the linear motor.

[0006] To achieve the above objectives, the present invention provides a linear motor comprising:

[0007] The shell has a receiving space;

[0008] The oscillator assembly includes a counterweight and a magnetic circuit structure. The counterweight has a mounting cavity, and the magnetic circuit structure is fixed to the cavity wall of the mounting cavity.

[0009] An elastic element, with its two ends connected to the housing and the counterweight respectively, suspends the oscillator assembly in the receiving space; and

[0010] A stator assembly is fixedly connected to the housing and is at least partially housed in the mounting cavity;

[0011] The mounting cavity has two first cavity walls that are arranged opposite each other in the vibration direction perpendicular to the oscillator assembly. The magnetic circuit structure includes two magnet assemblies disposed on the two first cavity walls. The magnet assembly includes a central magnet and two side magnets disposed on opposite sides of the central magnet. A magnetic guide plate is provided between the central magnet and the first cavity wall. The side magnets are fixedly connected to the first cavity wall.

[0012] In one embodiment, in the vibration direction perpendicular to the oscillator assembly, the thickness of the side magnet is equal to the sum of the thicknesses of the center magnet and the magnetic guide plate.

[0013] In one embodiment, the thickness of the magnetic guide plate is less than or equal to half the thickness of the central magnet.

[0014] In one embodiment, an assembly gap is provided between the magnetic guide plate and the side magnet along the vibration direction of the oscillator assembly.

[0015] In one embodiment, the assembly gap is less than or equal to 0.05 mm.

[0016] In one embodiment, the side magnet and the center magnet have the same thickness in the vibration direction perpendicular to the oscillator assembly, and the counterweight is provided with a mounting groove communicating with the mounting cavity, the mounting groove being used for mounting the magnetic guide plate.

[0017] In one embodiment, the magnetization directions of the central magnet and the side magnets are both perpendicular to the vibration direction of the oscillator assembly, and the magnetization directions of the central magnet and the side magnets are opposite.

[0018] In one embodiment, the magnetization directions of the opposing magnets in the two magnet assemblies are opposite.

[0019] In one embodiment, the mounting cavity further has two second cavity walls disposed opposite to each other along the vibration direction, and both second cavity walls are provided with clearance grooves.

[0020] The present invention also proposes an electronic device including the aforementioned linear motor.

[0021] In the technical solution of this invention, a housing with a receiving space is provided in the linear motor. An oscillator assembly, an elastic element, and a stator assembly are installed within the receiving space. The oscillator assembly includes a counterweight with a mounting cavity and a magnetic circuit structure fixed to the mounting cavity. The elastic element suspends the oscillator assembly in the receiving space. The stator assembly is fixedly connected to the housing and at least partially housed within the mounting cavity. The mounting cavity has two first cavity walls arranged opposite each other in a direction perpendicular to the vibration direction of the oscillator assembly. The magnetic circuit structure includes two magnet assemblies disposed on the two first cavity walls. Each magnet assembly includes a central magnet and two side magnets disposed on opposite sides of the central magnet. A magnetic guide plate is provided between the central magnet and the first cavity wall, and the side magnets are fixedly connected to the first cavity wall. Thus, compared to the prior art where the magnet assemblies are directly connected to the cavity walls of the mounting cavity, this invention provides a magnetic guide plate between the central magnet and the first cavity wall, thereby improving the effective utilization rate of the magnetic field lines, reducing magnetic leakage, and improving the efficiency of the linear motor. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1 is a partial structural schematic diagram of an embodiment of the linear motor provided by the present invention;

[0024] Figure 2 is a cross-sectional view of Figure 1.

[0025] Explanation of reference numerals: 100, Oscillator assembly; 110, Counterweight; 111, First cavity wall; 112, Second cavity wall; 115, Clearance groove; 116, Mounting cavity; 120, Magnetic circuit structure; 121, Side magnet; 122, Center magnet; 130, Magnetic guide plate; 131, Assembly gap; 200, Stator assembly; 210, Iron core; 220, Coil; 230, First magnetic pole shoe; 240, Second magnetic pole shoe.

[0026] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0029] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0030] In applications such as VR (Virtual Reality), AR (Augmented Reality), mobile phones, and tablets, linear motors are typically used as their vibration feedback units.

[0031] A linear motor is a device that converts electrical energy into mechanical energy using the principle of electromagnetic force generation. Generally, the structure of a linear motor includes an oscillator assembly suspended in a housing and a stator assembly fixed in the housing. The oscillator assembly includes a counterweight and a magnetic circuit structure fixed in a mounting cavity of the counterweight. At least part of the stator assembly is housed in the mounting cavity.

[0032] Currently, due to unreasonable magnetic circuit design or manufacturing defects, the magnetic field lines in linear motors may not be completely enclosed within the magnetic circuit, with some lines leaking to the outside, resulting in magnetic leakage. Magnetic leakage not only affects the operating efficiency of the linear motor but also generates additional electromagnetic interference, adversely affecting surrounding electronic equipment.

[0033] This invention proposes a linear motor.

[0034] Referring to Figures 1 and 2, in one embodiment of the present invention, the linear motor includes a housing, an oscillator assembly 100, an elastic element, and a stator assembly 200. The housing has a receiving space, within which the oscillator assembly 100, the elastic element, and the stator assembly 200 are all disposed. The oscillator assembly 100 includes a counterweight 110 and a magnetic circuit structure 120. The counterweight 110 has a mounting cavity 116, and the magnetic circuit structure 120 is fixed to the cavity wall of the mounting cavity 116. The two ends of the elastic element are respectively connected to the housing and the counterweight 110 to suspend the oscillator assembly 100 in the receiving space. The stator assembly 200 is fixedly connected to the housing and is at least partially received in the mounting cavity 116.

[0035] Understandably, the oscillator assembly 100 is suspended in the housing space, meaning it does not directly contact the housing. The stator assembly 200 includes an iron core 210 and a coil 220. The iron core 210 is fixedly connected to the inner wall of the housing, and the coil 220 is wound around the surface of the iron core 210. In one embodiment, the stator assembly 200 further includes a first magnetic pole shoe 230 and a second magnetic pole shoe 240 respectively fixed to the ends of the iron core 210. When the coil 220 is energized, the first magnetic pole shoe 230 and the second magnetic pole shoe 240 are then magnetized. Thus, when the linear motor operates, the coil 220 is energized to generate a magnetic field, and the iron core 210 generates an Ampere force under the action of the magnetic field. The counterweight 110 reciprocates under the action of the Ampere force generated by the stator assembly 200.

[0036] The mounting cavity 116 has two first cavity walls 111 arranged opposite each other in the vibration direction perpendicular to the oscillator assembly 100. The magnetic circuit structure 120 includes two magnet assemblies disposed on the two first cavity walls 111. The magnet assembly includes a central magnet 122 and two side magnets 121 disposed on opposite sides of the central magnet 122. A magnetic guide plate 130 is provided between the central magnet 122 and the first cavity wall 111, and the side magnets 121 are fixedly connected to the first cavity wall 111.

[0037] For ease of explanation, the vibration direction of the oscillator assembly 100 is defined as the left-right direction, the vibration direction perpendicular to the oscillator assembly 100 is defined as the front-back direction, and the direction of the stator assembly 200 toward and away from the mounting cavity 116 is defined as the up-down direction. In the front-back direction, the mounting cavity 116 has two opposing first cavity walls 111, and two magnet assemblies are respectively mounted on the first cavity walls 111. In the embodiment shown in the figures of this invention, the two magnet assemblies are symmetrically arranged, that is, the center magnet 122 at one first cavity wall 111 is opposite to the center magnet 122 at the other first cavity wall 111, and the side magnet 121 at one first cavity wall 111 is opposite to the side magnet 121 at the other first cavity wall 111.

[0038] Understandably, the magnetic guide plate 130 concentrates the magnetic field generated by the magnet assembly, improving the effective utilization rate of the magnetic field lines and reducing magnetic leakage, thereby improving the efficiency of the linear motor. It also provides electromagnetic shielding, reducing electromagnetic interference to surrounding electronic equipment. Furthermore, the magnetic guide plate 130 is only located at the central magnet 122, thus avoiding occupying more magnet mounting space, avoiding reducing the thickness of the magnet assembly, and consequently avoiding reducing the driving force of the linear motor. It also avoids occupying more space in the mounting cavity 116, thus avoiding reducing the mass of the counterweight 110, thereby ensuring the vibration effect of the linear motor.

[0039] In the technical solution of the present invention, a housing with a receiving space is provided in the linear motor. A vibrator assembly 100, an elastic element, and a stator assembly 200 are installed in the receiving space. The vibrator assembly 100 includes a counterweight 110 with a mounting cavity 116 and a magnetic circuit structure fixed to the mounting cavity 116. The elastic element is used to suspend the vibrator assembly 100 in the receiving space. The stator assembly 200 is fixedly connected to the housing and is at least partially received in the mounting cavity 116. The mounting cavity 116 has two first cavity walls 111 arranged opposite to each other in the vibration direction perpendicular to the vibrator assembly 100. The magnetic circuit structure includes two magnet assemblies disposed on the two first cavity walls 111. The magnet assemblies include a central magnet 122 and two side magnets 121 disposed on opposite sides of the central magnet 122. A magnetic guide plate 130 is provided between the central magnet 122 and the first cavity wall 111. The side magnets 121 are fixedly connected to the first cavity wall 111. Thus, compared to the existing technology where the magnet assembly is directly connected to the cavity wall of the mounting cavity 116, the present invention provides a magnetic guide plate 130 between the central magnet 122 and the first cavity wall 111, thereby improving the effective utilization rate of the magnetic field lines, reducing magnetic leakage, and improving the efficiency of the linear motor.

[0040] In an embodiment of the present invention, in the vibration direction perpendicular to the oscillator assembly 100, the thickness of the side magnet 121 is equal to the sum of the thicknesses of the center magnet 122 and the magnetic guide plate 130.

[0041] Understandably, there must be a gap between the magnet assembly and the stator assembly 200 to prevent the oscillator assembly 100 and the stator assembly 200 from contacting and interfering with each other. Thus, in one embodiment, the inner walls of the side magnet 121 and the center magnet 122 are flush. This is beneficial for setting the gap between the magnet assembly and the stator assembly 200, and also helps to ensure the thickness of the magnet assembly, thereby ensuring the driving force of the linear motor.

[0042] In the embodiment shown in the figures of this invention, the thickness of the side magnet 121 is the same as the sum of the thicknesses of the central magnet 122 and the magnetic guide plate 130. Thus, the inner wall of the side magnet 121 is flush with the inner wall of the central magnet 122, and the outer wall of the side magnet 121 is flush with the outer wall of the magnetic guide plate 130. This facilitates the setting of the mounting cavity 116 on the counterweight 110 and simplifies the processing and forming of the counterweight 110.

[0043] In an embodiment of the present invention, the thickness of the magnetic guide plate 130 is less than or equal to half the thickness of the central magnet 122. It is understood that the thicker the magnet, the stronger the driving force of the linear motor. To avoid affecting the driving force of the linear motor, the thickness of the magnetic guide plate 130 is less than or equal to half the thickness of the central magnet 122. This ensures both the driving force of the linear motor and improves the effective utilization rate of the magnetic field lines.

[0044] In an embodiment of the present invention, an assembly gap 131 is provided between the magnetic guide plate 130 and the side magnet 121 along the vibration direction of the oscillator assembly 100. This assembly gap 131 facilitates the installation of the magnetic circuit structure 120 and improves the assembly efficiency of the linear motor. In one embodiment, the assembly gap is less than or equal to 0.05 mm. In another embodiment, the magnetic guide plate 130 and the side magnet 121 can also be directly attached. The size of the assembly gap 131 is not limited here.

[0045] In an embodiment of the present invention, in the vibration direction perpendicular to the oscillator assembly 100, the side magnet 121 and the center magnet 122 have the same thickness, and the counterweight 110 is provided with a mounting groove that communicates with the mounting cavity 116. The mounting groove is used for mounting the magnetic guide plate 130.

[0046] Understandably, in one embodiment, the edge magnet 121 and the central magnet 122 have the same thickness, and a magnetic guide plate 130 is also installed on the outer wall of the central magnet 122. Thus, the magnetic guide plate 130 protrudes outward compared to the edge magnet 121. The counterweight 110 has a mounting groove communicating with the mounting cavity 116, and the magnetic guide plate 130 is installed on the groove wall. This also allows for the installation of the magnetic circuit structure 120 and the magnetic guide plate 130.

[0047] In embodiments of the present invention, the magnetization directions of the central magnet 122 and the side magnets 121 are both perpendicular to the vibration direction of the oscillator assembly 100. This allows the magnetic field lines to form a denser closed loop, thereby reducing magnetic leakage in the vertical direction of the magnet assembly, improving the efficiency of the linear motor, and reducing additional electromagnetic interference. The magnetization directions of the central magnet 122 and the side magnets 121 are opposite. Thus, on the one hand, the opposite magnetization directions of adjacent central magnets 122 and side magnets 121 allow the magnetic field lines to form a denser closed loop, thereby reducing magnetic leakage in the vertical direction of the magnet assembly, improving the efficiency of the linear motor, and reducing additional electromagnetic interference. On the other hand, the opposite magnetization directions of adjacent central magnets 122 and side magnets 121 improve the effective utilization rate of the magnetic field lines, which is beneficial for driving the reciprocating vibration of the counterweight 110 and increasing the driving force of the linear motor.

[0048] In an embodiment of the invention, the magnetization directions of the opposing magnets in the two magnet assemblies are opposite; that is, the magnetization directions of the center magnets 122 of the two magnet assemblies are opposite, and the magnetization directions of the opposing side magnets 121 of the two magnet assemblies are opposite. This ensures that the forces exerted by the two magnet assemblies on the coil 220 are in the same direction, thereby increasing the driving force.

[0049] In the embodiment shown in the figures of this invention, the magnetization direction of the magnet assembly is defined as follows:

[0050] The magnetization direction of the side magnet 121 is from the inner wall of the side magnet 121 to the outer wall of the side magnet 121.

[0051] The magnetization direction of the central magnet 122 is from the outer side wall of the central magnet 122 to the inner side wall of the central magnet 122.

[0052] In one embodiment, the projection of the central magnet 122 falls on the stator assembly 200 along the vibration direction perpendicular to the oscillator assembly 100. Specifically, the length of the stator assembly 200 is greater than or equal to the length of the central magnet 122 in the left-right direction, so that the stator assembly 200 can directly interact with the side magnet 121, which is beneficial to improving the driving force of the linear motor.

[0053] In an embodiment of the present invention, the mounting cavity 116 further includes two second cavity walls 112 disposed opposite to each other along the vibration direction, and each of the two second cavity walls 112 is provided with a clearance groove 115. It is understood that the clearance groove 115 increases the vibration space of the oscillator assembly 100, avoids collision between the stator assembly 200 and the second cavity wall 112 when the linear motor vibrates, improves the operational stability of the linear motor, and enhances the operational reliability of the electronic device.

[0054] This invention also proposes an electronic device comprising a linear motor. The specific structure of the linear motor is described in the above embodiments. Since this electronic device adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated upon here. The electronic device may be a mobile phone, smart glasses, a smart ring, a smartwatch, etc.

[0055] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A linear motor, characterized in that, include: The shell has a receiving space; The oscillator assembly includes a counterweight and a magnetic circuit structure. The counterweight has a mounting cavity, and the magnetic circuit structure is fixed to the cavity wall of the mounting cavity. An elastic element, with its two ends connected to the housing and the counterweight respectively, suspends the oscillator assembly in the receiving space; as well as A stator assembly is fixedly connected to the housing and is at least partially housed in the mounting cavity; The mounting cavity has two first cavity walls that are arranged opposite each other in the vibration direction perpendicular to the oscillator assembly. The magnetic circuit structure includes two magnet assemblies disposed on the two first cavity walls. The magnet assembly includes a central magnet and two side magnets disposed on opposite sides of the central magnet. A magnetic guide plate is provided between the central magnet and the first cavity wall. The side magnets are fixedly connected to the first cavity wall.

2. The linear motor as described in claim 1, characterized in that, In the vibration direction perpendicular to the oscillator assembly, the thickness of the side magnet is equal to the sum of the thicknesses of the center magnet and the magnetic guide plate.

3. The linear motor as described in claim 2, characterized in that, The thickness of the magnetic guide plate is less than or equal to half the thickness of the central magnet.

4. The linear motor as described in claim 1, characterized in that, Along the vibration direction of the oscillator assembly, there is an assembly gap between the magnetic guide plate and the side magnet.

5. The linear motor as described in claim 4, characterized in that, The assembly gap is less than or equal to 0.05 mm.

6. The linear motor as described in claim 1, characterized in that, In the vibration direction perpendicular to the oscillator assembly, the thickness of the side magnet and the center magnet are the same, and the counterweight is provided with a mounting groove that communicates with the mounting cavity. The mounting groove is used for mounting the magnetic guide plate.

7. The linear motor as described in claim 1, characterized in that, The magnetization directions of the central magnet and the side magnets are both perpendicular to the vibration direction of the oscillator assembly, and the magnetization directions of the central magnet and the side magnets are opposite.

8. The linear motor as described in claim 7, characterized in that, The magnets of the two magnet assemblies are magnetized in opposite directions.

9. The linear motor according to any one of claims 1 to 8, characterized in that, The mounting cavity also has two second cavity walls arranged opposite each other along the vibration direction, and both second cavity walls are provided with avoidance grooves.

10. An electronic device, characterized in that, Including the linear motor as described in any one of claims 1 to 9.

Images