Linear motor and electronic device

Abstract

The invention discloses a linear motor and electronic equipment, and relates to the technical field of linear motors, the linear motor comprises a shell with an accommodating space, and an oscillator assembly, a stator assembly and an elastic piece which are arranged in the accommodating space, and the oscillator assembly comprises a balancing weight with a mounting cavity and a magnetic circuit structure fixed in the mounting cavity; the elastic piece is connected with the shell and the balancing weight so as to suspend the vibrator assembly in the accommodating space; the stator assembly is fixedly connected with the shell, and at least part of the stator assembly is accommodated in the mounting cavity; the installation cavity is provided with two first cavity walls which are oppositely arranged in the vibration direction perpendicular to the vibrator assembly, the magnetic circuit structure comprises two magnetic steel assemblies arranged on the two first cavity walls respectively, each magnetic steel assembly comprises a central magnetic steel and two side magnetic steels arranged on the two sides of the central magnetic steel respectively, and a magnetic conductive plate is arranged between the central magnetic steel and the first cavity walls. And the side magnetic steel is fixedly connected with the first cavity wall. According to the technical scheme provided by the invention, the efficiency of the linear motor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of linear motors, and in particular to a linear motor and an electronic device. Background Art

[0002] In application fields such as VR (Virtual Reality), AR (Augmented Reality), mobile phones, and tablet computers, linear motors are usually used as vibration feedback units.

[0003] A linear motor is a device that converts electrical energy into mechanical energy using the principle of electromagnetic force. Generally, the structure of a linear motor includes a vibrator assembly suspended in a housing and a stator assembly fixed in the housing, wherein the vibrator assembly includes a counterweight block and a magnetic circuit structure fixed in a mounting cavity of the counterweight block, and at least part of the stator assembly is accommodated in the mounting cavity.

[0004] At present, due to unreasonable magnetic circuit design or manufacturing process defects, the magnetic field lines in the linear motor may not be completely enclosed inside the magnetic circuit, but part of the magnetic field lines leak out of the magnetic circuit, forming magnetic leakage. Magnetic leakage will affect the operating efficiency of the linear motor. Summary of the invention

[0005] The main purpose of the present invention is to provide a linear motor and an electronic device, aiming to improve the efficiency of the linear motor.

[0006] To achieve the above object, the linear motor proposed in the present invention comprises:

[0007] A shell having a receiving space;

[0008] The vibrator assembly comprises a counterweight block and a magnetic circuit structure, wherein the counterweight block is provided with an installation cavity, and the magnetic circuit structure is fixed to the cavity wall of the installation cavity;

[0009] an elastic member, two ends of which are respectively connected to the housing and the counterweight block, so as to suspend the vibrator assembly in the receiving space; and

[0010] a stator assembly, fixedly connected to the housing and at least partially accommodated in the mounting cavity;

[0011] The mounting cavity has two first cavity walls arranged opposite to each other in a vibration direction perpendicular to the vibrator assembly. The magnetic circuit structure includes two magnetic steel assemblies respectively arranged on the two first cavity walls. The magnetic steel assembly includes a central magnetic steel and two side magnetic steels respectively arranged on opposite sides of the central magnetic steel. A magnetic conductive plate is provided between the central magnetic steel and the first cavity wall, and the side magnetic steel is fixedly connected to the first cavity wall.

[0012] In one embodiment, in a vibration direction perpendicular to the vibrator assembly, the thickness of the side magnetic steel is equal to the sum of the thicknesses of the center magnetic steel and the magnetic conductive plate.

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

[0014] In one embodiment, an assembly gap is provided between the magnetic conductive plate and the edge magnetic steel along the vibration direction of the vibrator assembly.

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

[0016] In one embodiment, in a vibration direction perpendicular to the vibrator assembly, the side magnetic steel and the center magnetic steel have the same thickness, and the counterweight block is provided with an installation groove connected to the installation cavity, and the installation groove is used for the installation of the magnetic conductive plate.

[0017] In one embodiment, the magnetization directions of the central magnetic steel and the side magnetic steel are both perpendicular to the vibration direction of the vibrator assembly, and the magnetization directions of the central magnetic steel and the side magnetic steel are opposite.

[0018] In one embodiment, the magnetization directions of the magnets of the two magnet assemblies facing each other are opposite.

[0019] In one embodiment, the installation cavity further has two second cavity walls arranged opposite to each other along the vibration direction, and both of the two second cavity walls are provided with an avoidance groove.

[0020] The present invention also provides an electronic device, comprising the linear motor.

[0021] In the technical solution of the present invention, a shell with a receiving space is provided in the linear motor, and a vibrator assembly, an elastic member and a stator assembly are installed in the receiving space, wherein the vibrator assembly includes a counterweight block provided with an installation cavity and a magnetic circuit structure fixed to the installation cavity, the elastic member is used to suspend the vibrator assembly in the receiving space, the stator assembly is fixedly connected to the shell and at least partially received in the installation cavity, the installation 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 includes two magnetic steel assemblies arranged in the two first cavity walls, the magnetic steel assembly includes a central magnetic steel and two side magnetic steels arranged on opposite sides of the central magnetic steel, a magnetic conductive plate is provided between the central magnetic steel and the first cavity wall, and the side magnetic steel is fixedly connected to the first cavity wall. In this way, compared with the solution in the prior art in which the magnetic steel assembly is directly connected to the cavity wall of the installation cavity, the present invention provides a magnetic conductive plate between the central magnetic steel 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

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

[0024] Figure 2 for Figure 1 sectional view of .

[0025] Description of Figure Numbers:

[0026] 100, vibrator assembly; 110, counterweight; 111, first cavity wall; 112, second cavity wall; 115, avoidance groove; 116, installation cavity;

[0027] 120, magnetic circuit structure; 121, side magnetic steel; 122, center magnetic steel; 130, magnetic guide plate; 131, assembly gap;

[0028] 200, stator assembly; 210, iron core; 220, coil; 230, first magnetic conductive pole shoe; 240, second magnetic conductive pole shoe.

[0029] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] 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 position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] In application fields such as VR (Virtual Reality), AR (Augmented Reality), mobile phones, and tablet computers, linear motors are usually used as vibration feedback units.

[0034] A linear motor is a device that converts electrical energy into mechanical energy using the principle of electromagnetic force. Generally, the structure of a linear motor includes a vibrator assembly suspended in a housing and a stator assembly fixed in the housing, wherein the vibrator assembly includes a counterweight block and a magnetic circuit structure fixed in a mounting cavity of the counterweight block, and at least part of the stator assembly is accommodated in the mounting cavity.

[0035] At present, due to unreasonable magnetic circuit design or manufacturing process defects, the magnetic field lines in the linear motor may not be completely enclosed inside the magnetic circuit, but part of the magnetic field lines leak outside the magnetic circuit, forming magnetic leakage. Magnetic leakage not only affects the operating efficiency of the linear motor, but also generates additional electromagnetic interference, causing adverse effects on surrounding electronic equipment.

[0036] The invention provides a linear motor.

[0037] See also Figure 1 and Figure 2 In one embodiment of the present invention, the linear motor includes a housing, a vibrator assembly 100, an elastic member, and a stator assembly 200, wherein the housing has a receiving space, the vibrator assembly 100, the elastic member, and the stator assembly 200 are all arranged in the receiving space, the vibrator assembly 100 includes a counterweight 110 and a magnetic circuit structure 120, the counterweight 110 is provided with 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 member are respectively connected to the housing and the counterweight 110, so as to suspend the vibrator assembly 100 in the receiving space. The stator assembly 200 is fixedly connected to the housing, and at least partially accommodated in the mounting cavity 116.

[0038] It can be understood that the vibrator assembly 100 is suspended in the receiving space, that is, the vibrator assembly 100 is not in direct contact with the shell. 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 shell, and the coil 220 is wound on the surface of the iron core 210. In one embodiment, the stator assembly 200 also includes a first magnetic pole shoe 230 and a second magnetic pole shoe 240 respectively fixed to the ends of the iron core 210. After the coil 220 is energized, the first magnetic pole shoe 230 and the second magnetic pole shoe 240 are then magnetized. In this way, when the linear motor is working, the coil 220 is energized to generate a magnetic field, the iron core 210 generates an Ampere force under the action of the magnetic field, and the counterweight 110 reciprocates under the action of the Ampere force generated by the stator assembly 200.

[0039] The mounting cavity 116 has two first cavity walls 111 arranged opposite to each other in a vibration direction perpendicular to the vibrator assembly 100. The magnetic circuit structure 120 includes two magnetic steel assemblies respectively arranged on the two first cavity walls 111. The magnetic steel assemblies include a central magnetic steel 122 and two side magnetic steels 121 respectively arranged on opposite sides of the central magnetic steel 122. A magnetic conductive plate 130 is provided between the central magnetic steel 122 and the first cavity wall 111. The side magnetic steel 121 is fixedly connected to the first cavity wall 111.

[0040] For the convenience of explanation, the vibration direction of the vibrator assembly 100 is defined as the left-right direction, the vibration direction perpendicular to the vibrator assembly 100 is defined as the front-to-back direction, and the direction of the stator assembly 200 toward and away from the installation cavity 116 is defined as the up-down direction. In the front-to-back direction, the installation cavity 116 has two first cavity walls 111 arranged opposite to each other, and the two magnetic steel assemblies are respectively installed at the first cavity walls 111. In the scheme shown in the figure of the present invention, the two magnetic steel assemblies are symmetrically arranged, that is, the central magnetic steel 122 at one first cavity wall 111 is arranged opposite to the central magnetic steel 122 at the other first cavity wall 111, and the side magnetic steel 121 at one first cavity wall 111 is arranged opposite to the side magnetic steel 121 at the other first cavity wall 111.

[0041] It can be understood that the arrangement of the magnetic conductive plate 130 can concentrate the magnetic field generated by the magnetic steel assembly, improve the effective utilization rate of the magnetic field lines, reduce magnetic leakage, and thus improve the efficiency of the linear motor. At the same time, it can also achieve the effect of electromagnetic shielding and reduce the electromagnetic interference caused to surrounding electronic equipment. In addition, the magnetic conductive plate 130 is only arranged at the center magnetic steel 122, so as to avoid occupying more magnetic steel installation space, avoid reducing the thickness of the magnetic steel assembly, and thus avoid reducing the driving force of the linear motor. It can also avoid occupying more space in the installation cavity 116, thereby avoiding reducing the mass of the counterweight block 110, thereby ensuring the vibration effect of the linear motor.

[0042] In the technical solution of the present invention, a shell with a receiving space is provided in the linear motor, and a vibrator assembly 100, an elastic member and a stator assembly 200 are installed in the receiving space, wherein the vibrator assembly 100 includes a counterweight block 110 provided with an installation cavity 116 and a magnetic circuit structure fixed to the installation cavity 116, the elastic member is used to suspend the vibrator assembly 100 in the receiving space, the stator assembly 200 is fixedly connected to the shell and is at least partially accommodated in the installation cavity 116, the installation cavity 116 has two first cavity walls 111 arranged opposite to each other in a vibration direction perpendicular to the vibrator assembly 100, the magnetic circuit structure includes two magnetic steel assemblies respectively arranged in the two first cavity walls 111, the magnetic steel assembly includes a central magnetic steel 122 and two side magnetic steels 121 respectively arranged on opposite sides of the central magnetic steel 122, a magnetic conductive plate 130 is provided between the central magnetic steel 122 and the first cavity wall 111, and the side magnetic steel 121 is fixedly connected to the first cavity wall 111. Thus, compared with the solution in the prior art in which the magnetic steel assembly is directly connected to the cavity wall of the mounting cavity 116, the present invention provides a magnetic conductive plate 130 between the central magnetic steel 122 and the first cavity wall 111, thereby improving the effective utilization rate of the magnetic field lines, reducing leakage magnetic flux, and improving the efficiency of the linear motor.

[0043] In the embodiment of the present invention, in the vibration direction perpendicular to the vibrator assembly 100 , the thickness of the side magnetic steel 121 is equal to the sum of the thickness of the center magnetic steel 122 and the magnetic conductive plate 130 .

[0044] It is understandable that there must be a spacing distance between the magnetic steel assembly and the stator assembly 200 so that the vibrator assembly 100 and the stator assembly 200 do not contact and interfere. Thus, in one embodiment, the inner side walls of the side magnetic steel 121 and the center magnetic steel 122 are flush, which is beneficial to setting the spacing distance between the magnetic steel assembly and the stator assembly 200 on the one hand, and also beneficial to ensuring the thickness of the magnetic steel assembly, thereby ensuring the driving force of the linear motor.

[0045] In the scheme shown in the figure of the present invention, the thickness of the side magnetic steel 121 is consistent with the sum of the thickness of the center magnetic steel 122 and the magnetic conductive plate 130. In this way, the inner wall of the side magnetic steel 121 is flush with the inner wall of the center magnetic steel 122, and the outer wall of the side magnetic steel 121 is flush with the outer wall of the magnetic conductive plate 130, thereby facilitating the setting of the installation cavity 116 on the counterweight block 110 and helping to simplify the processing and forming of the counterweight block 110.

[0046] In the embodiment of the present invention, the thickness of the magnetic plate 130 is less than or equal to half the thickness of the central magnetic steel 122. It can be understood that the thicker the magnetic steel piece is, the stronger the driving force of the linear motor is. In order to avoid affecting the driving force of the linear motor, the thickness of the magnetic plate 130 is less than or equal to half the thickness of the central magnetic steel 122, so that the driving force of the linear motor can be guaranteed and the effective utilization rate of the magnetic field lines can be improved.

[0047] In an embodiment of the present invention, an assembly gap 131 is provided between the magnetic conductive plate 130 and the side magnetic steel 121 along the vibration direction of the vibrator assembly 100. In this way, the provision of the 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 one embodiment, the magnetic conductive plate 130 and the side magnetic steel 121 may also be directly fitted together. Here, there is no restriction on the size of the assembly gap 131.

[0048] In an embodiment of the present invention, in the vibration direction perpendicular to the vibrator assembly 100, the thickness of the side magnetic steel 121 and the center magnetic steel 122 are consistent, and the counterweight block 110 is provided with an installation groove connected to the installation cavity 116, and the installation groove is used for the installation of the magnetic conductive plate 130.

[0049] It can be understood that in one embodiment, the thickness of the side magnetic steel 121 and the center magnetic steel 122 is consistent, and the outer wall of the center magnetic steel 122 is also installed with a magnetic conductive plate 130. In this way, compared with the side magnetic steel 121, the magnetic conductive plate 130 is arranged to protrude outward. The counterweight block 110 is provided with a mounting groove connected to the mounting cavity 116, and the magnetic conductive plate 130 is installed on the groove wall of the mounting groove. In this way, the installation of the magnetic circuit structure 120 and the magnetic conductive plate 130 can also be achieved.

[0050] In an embodiment of the present invention, the magnetizing directions of the center magnetic steel 122 and the side magnetic steel 121 are both perpendicular to the vibration direction of the vibrator assembly 100. In this way, the magnetic flux lines can form a denser closed loop, thereby reducing the magnetic flux leakage in the up and down directions of the magnetic steel assembly, thereby improving the efficiency of the linear motor and reducing additional electromagnetic interference. The magnetizing directions of the center magnetic steel 122 and the side magnetic steel 121 are opposite. In this way, on the one hand, the magnetizing directions of the adjacent center magnetic steel 122 and the side magnetic steel 121 are opposite, so that the magnetic flux lines can form a denser closed loop, thereby reducing the magnetic flux leakage in the up and down directions of the magnetic steel assembly, thereby improving the efficiency of the linear motor and reducing additional electromagnetic interference. On the other hand, the magnetizing directions of the adjacent center magnetic steel 122 and the side magnetic steel 121 are opposite, which improves the effective utilization rate of the magnetic flux lines, is conducive to promoting the reciprocating vibration of the counterweight block 110, and improves the driving force of the linear motor.

[0051] In the embodiment of the present invention, the magnetization directions of the magnets of 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 side magnets 121 of the two magnet assemblies are opposite. Thus, the acting forces of the two magnet assemblies and the coil 220 are in the same direction, so as to increase the driving force.

[0052] In the scheme shown in the figure of the present invention, the magnetization direction of the magnetic steel assembly is defined as follows:

[0053] The magnetization direction of the edge magnetic steel 121 is from the inner wall of the edge magnetic steel 121 to the outer wall of the edge magnetic steel 121;

[0054] The magnetization direction of the central magnetic steel 122 is from the outer wall of the central magnetic steel 122 to the inner wall of the central magnetic steel 122 .

[0055] In one embodiment, along the vibration direction perpendicular to the vibrator assembly 100, the projection of the center magnetic steel 122 falls on the stator assembly 200. Specifically, along the left-right direction, the length of the stator assembly 200 is greater than or equal to the length of the center magnetic steel 122, so that the stator assembly 200 can directly interact with the side magnetic steel 121, which is beneficial to improve the driving force of the linear motor.

[0056] In the embodiment of the present invention, the installation cavity 116 further has two second cavity walls 112 arranged opposite to each other along the vibration direction, and both second cavity walls 112 are provided with avoidance grooves 115. It can be understood that the arrangement of the avoidance grooves 115 increases the vibration space of the vibrator assembly 100, avoids the collision between the stator assembly 200 and the second cavity walls 112 when the linear motor vibrates, improves the use stability of the linear motor, and improves the use reliability of the electronic equipment.

[0057] The present invention further proposes an electronic device, which includes a linear motor. The specific structure of the linear motor refers to the above embodiment. Since the electronic device adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here. Among them, the electronic device can be a mobile phone, smart glasses, smart ring, smart watch, etc.

[0058] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A linear motor, characterized in that: include: A shell having a receiving space; The vibrator assembly comprises a counterweight block and a magnetic circuit structure, wherein the counterweight block is provided with an installation cavity, and the magnetic circuit structure is fixed to the cavity wall of the installation cavity; An elastic member, two ends of which are respectively connected to the housing and the counterweight block, so as to suspend the vibrator assembly in the receiving space; as well as a stator assembly, fixedly connected to the housing and at least partially accommodated in the mounting cavity; The mounting cavity has two first cavity walls arranged opposite to each other in a vibration direction perpendicular to the vibrator assembly. The magnetic circuit structure includes two magnetic steel assemblies respectively arranged on the two first cavity walls. The magnetic steel assembly includes a central magnetic steel and two side magnetic steels respectively arranged on opposite sides of the central magnetic steel. A magnetic conductive plate is provided between the central magnetic steel and the first cavity wall, and the side magnetic steel is fixedly connected to the first cavity wall.

2. The linear motor according to claim 1, wherein: In a vibration direction perpendicular to the vibrator assembly, the thickness of the side magnetic steel is equal to the sum of the thickness of the central magnetic steel and the magnetic conductive plate.

3. The linear motor according to claim 2, wherein: The thickness of the magnetic conductive plate is less than or equal to half of the thickness of the central magnetic steel.

4. The linear motor according to claim 1, wherein: Along the vibration direction of the vibrator assembly, an assembly gap is provided between the magnetic conductive plate and the edge magnetic steel.

5. The linear motor according to claim 4, wherein: The assembly gap is less than or equal to 0.05 mm.

6. The linear motor according to claim 1, wherein: In a vibration direction perpendicular to the vibrator assembly, the side magnetic steel has the same thickness as the center magnetic steel, and the counterweight block is provided with a mounting groove connected to the mounting cavity, and the mounting groove is used for the installation of the magnetic conductive plate.

7. The linear motor according to claim 1, wherein: The magnetizing directions of the central magnetic steel and the side magnetic steel are both perpendicular to the vibration direction of the vibrator assembly, and the magnetizing directions of the central magnetic steel and the side magnetic steel are opposite.

8. The linear motor according to claim 7, wherein: The magnetizing directions of the magnets of the two magnet assemblies facing each other are opposite.

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

10. An electronic device, characterized in that: Comprising a linear motor as claimed in any one of claims 1 to 9.

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