Linear motor and electronic device
By using Hall sensors instead of induction coils in linear motors, and combining them with drive coils to achieve drive vibration and displacement detection, the problems of increased linear motor size and poor user experience are solved, achieving space saving and improved tactile experience.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUHAN JUXIN MICROELECTRONICS CO LTD
- Filing Date
- 2025-07-31
- Publication Date
- 2026-07-21
AI Technical Summary
Existing linear motors suffer from increased size and poor tactile experience during vibration and displacement detection. In particular, the induction coils in the closed-loop control structure are large and difficult to arrange inside the motor. Hall sensors need to be precisely distributed to achieve good measurements.
Hall sensors are used to replace induction coils. The position of the moving part is determined by the magnetic field strength of the moving part magnet. Combined with the drive coil, the driving vibration and displacement detection are realized. The arrangement direction of the Hall sensors and the moving part magnet intersects with the displacement direction of the moving part assembly, and the setting is made using the internal space of the linear motor.
It achieves both drive vibration and mover component displacement detection, while saving internal space in the linear motor, improving the user's tactile experience, and the small size of the Hall sensor facilitates the stacking of linear motors in electronic devices.
Smart Images
Figure CN224537977U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of motor technology, and more particularly to a linear motor and electronic device. Background Technology
[0002] Linear motors (Linear Resonant Accelerators, LRAs) are widely used in the field of haptic feedback due to their advantages such as small size, long lifespan, low power consumption, and fast response time. They are typically found in electronic devices such as smartphones and smartwatches.
[0003] Currently, linear motors with open-loop control structures obtain the displacement of the mover by measuring the back electromotive force of the drive coil, and then adjust the vibration effect according to the mover displacement to improve the user's tactile experience. However, since linear motors need to perform drive vibration and displacement detection at different time periods, meaning that the drive signal is disconnected when the mover displacement is detected, it will adversely affect the user's tactile experience.
[0004] Linear motors with closed-loop control structures can have separate drive coils and induction coils. The induction coils monitor the displacement of the mover in real time, allowing the drive and sensing phases to occur simultaneously, improving the user's tactile experience. However, the induction coils are relatively large and difficult to install inside the motor, increasing its overall size. To address this, Hall effect sensors can be used to measure the mover's position instead of induction coils. However, the distribution of Hall effect sensors relative to the mover requires careful planning to achieve optimal measurement results.
[0005] Therefore, there is an urgent need to provide a linear motor that can solve the above problems. Summary of the Invention
[0006] In view of this, the present disclosure provides a linear motor and an electronic device.
[0007] To achieve the above objectives, the technical solution disclosed herein is implemented as follows:
[0008] In a first aspect, embodiments of this disclosure provide a linear motor, comprising: a base, and a vibration module and a sensing module disposed above the base; the vibration module includes a drive coil and a mover assembly arranged along a first direction, the mover assembly including a mover magnet, the first direction being perpendicular to the surface of the base; the sensing module includes at least one Hall sensor, the Hall sensor being configured to obtain the position of the mover assembly based on the magnetic field strength of the mover magnet, thereby determining the displacement of the mover assembly; wherein the arrangement direction of the Hall sensor and the mover magnet intersects with the displacement direction of the mover assembly, the displacement direction being parallel to the surface of the base.
[0009] In some embodiments, along the first direction, the sensing position of the Hall sensor is below the top of the actuator assembly and above the bottom of the actuator assembly.
[0010] In some embodiments, the moving magnet includes a first magnet and a second magnet arranged along the displacement direction, both the first magnet and the second magnet having north and south magnetic poles; the north and south magnetic poles of the first magnet and the north and south magnetic poles of the second magnet are opposite to and parallel to the first direction.
[0011] In some embodiments, along the first direction, the sensing position of the Hall sensor is at the same height as the north-south pole junction of the first magnet and the north-south pole junction of the second magnet.
[0012] In some embodiments, the projection of the Hall sensor on the base overlaps with the projection of the moving part assembly on the base.
[0013] In some embodiments, along the first direction, the Hall sensor and the drive coil are located on opposite sides of the mover assembly.
[0014] In some embodiments, along the first direction, the Hall sensor and the drive coil are located on the same side of the mover assembly.
[0015] In some embodiments, the system further includes a stator assembly and a spring; the stator assembly surrounds the vibration module and the sensing module, and the spring connects the mover assembly and the stator assembly.
[0016] Secondly, embodiments of this disclosure also provide an electronic device, including a linear motor and a drive module as described in any of the above embodiments; the drive module is connected to the linear motor, the drive module is configured to provide a drive signal to the linear motor, and receive the displacement of the moving part of the sensor module output; the drive module is further configured to adjust the drive signal according to the displacement to adjust the amplitude of the vibration module.
[0017] This disclosure provides a linear motor and an electronic device. The linear motor includes a base, and a vibration module and a sensing module disposed above the base; the vibration module includes a drive coil and a mover assembly arranged along a first direction, the mover assembly including a mover magnet, the first direction being perpendicular to the surface of the base; the sensing module includes at least one Hall sensor, the Hall sensor being configured to obtain the position of the mover assembly based on the magnetic field strength of the mover magnet, thereby determining the displacement of the mover assembly; wherein the arrangement direction of the Hall sensor and the mover magnet intersects with the displacement direction of the mover assembly, the displacement direction being parallel to the surface of the base.
[0018] In this embodiment, when the drive coil receives a drive signal, the drive coil interacts with the mover magnet to generate an Ampere force, causing the mover assembly to displace. This changes the relative position of the Hall sensor and the mover assembly. The Hall sensor determines the position of the mover assembly in real time based on the magnetic field strength of the mover magnet, thereby determining the displacement of the mover assembly. Therefore, this embodiment can simultaneously achieve drive vibration and mover assembly displacement detection using both the drive coil and the Hall sensor. Furthermore, due to the small size of the Hall sensor, it can be installed within the internal space of the linear motor, saving internal space and facilitating the stacking of linear motors in electronic devices. Attached Figure Description
[0019] Figure 1 A three-dimensional perspective view of a linear motor provided in an embodiment of this disclosure;
[0020] Figure 2 This is a schematic diagram of the magnetic field lines distribution of the mover magnet provided in an embodiment of the present disclosure;
[0021] Figure 3 This is a schematic diagram showing the relative positions of a Hall sensor and a moving magnet according to an embodiment of the present disclosure;
[0022] Figure 4 for Figure 3 The diagram shows the relationship between the magnetic field strength of the mover magnet sensed by the Hall sensor and the displacement of the mover assembly.
[0023] Figure 5 This is a schematic diagram showing the relative positions of the Hall sensor and the moving magnet according to another embodiment of the present disclosure;
[0024] Figure 6 for Figure 5 The diagram shows the relationship between the magnetic field strength of the mover magnet sensed by the Hall sensor and the displacement of the mover assembly.
[0025] Figure 7 A schematic diagram showing the relative positions of the Hall sensor and the moving magnet provided in yet another embodiment of this disclosure;
[0026] Figure 8 for Figure 7 The diagram shows the relationship between the magnetic field strength of the mover magnet sensed by the Hall sensor and the displacement of the mover assembly.
[0027] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. Detailed Implementation
[0028] The technical solutions of the embodiments of this disclosure 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 this disclosure, and not all of them. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.
[0029] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of this disclosure. However, it will be apparent to those skilled in the art that this disclosure may be practiced without one or more of these details. In other instances, to avoid confusion with this disclosure, certain technical features well-known in the art have not been described; that is, not all features of actual embodiments are described herein, nor are well-known functions and structures described in detail.
[0030] In the accompanying drawings, for clarity, the dimensions of layers, areas, and elements, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.
[0031] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this disclosure, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion. And the discussion of a second element, component, area, layer, or portion does not imply that the first element, component, area, layer, or portion necessarily exists in this disclosure.
[0032] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.
[0033] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprise” and / or “comprising,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.
[0034] To fully understand this disclosure, detailed steps and structures will be presented in the following description to illustrate the technical solutions of this disclosure. Preferred embodiments of this disclosure are described in detail below; however, other embodiments may also be implemented in addition to these detailed descriptions.
[0035] In related technologies, linear motors with closed-loop control structures can have separate drive coils and induction coils. The induction coils monitor the displacement of the mover in real time, allowing the drive and sensing phases to occur simultaneously, improving the user's tactile experience. However, the induction coils are relatively large and difficult to arrange inside the motor, increasing its overall size. To address this, Hall effect sensors can be used to measure the mover's position instead of induction coils. However, the distribution of the Hall effect sensors relative to the mover needs careful planning to achieve optimal measurement results.
[0036] It should be noted that although both voice coil motors and vibration motors are linear motors, voice coil motors are primarily used for lens stabilization or focusing, i.e., for precise positioning of the lens or slide in the camera assembly. Therefore, precise feedback and rapid control are required for the position measurement of the mover. Vibration motors, on the other hand, mainly generate tactile feedback through rapid reciprocating vibration, and thus their position measurement of the mover is relatively less precise. The embodiments disclosed herein aim to achieve better mover position measurement performance by incorporating Hall sensors in the vibration motor and planning the distribution of the Hall sensors relative to the mover.
[0037] In view of this, the present disclosure provides a linear motor that can solve the above-mentioned problems.
[0038] It should be noted that, for ease of description, the various directions that may be used in the following description are defined first. The direction perpendicular to the base surface is defined as the Z direction (first direction), and the X direction and Y direction (second direction) are defined in a plane parallel to the base surface. The X direction is the displacement direction of the moving part assembly, and the X and Y directions can be perpendicular to each other.
[0039] Figure 1 A three-dimensional perspective view of a linear motor provided for an embodiment of this disclosure. See also: Figure 1 The linear motor includes: a base 10, and a vibration module and a sensing module disposed above the base 10;
[0040] The vibration module includes a drive coil 20 and a mover assembly 30 arranged along a first direction. The mover assembly 30 includes a mover magnet 310, and the first direction is perpendicular to the surface of the base 10.
[0041] The sensing module includes at least one Hall sensor, which is configured to determine the position of the mover assembly 30 based on the magnetic field strength of the mover magnet 310, so as to determine the displacement of the mover assembly 30; wherein the arrangement direction of the Hall sensor and the mover magnet 310 (e.g., the Y direction or the Z direction) intersects the displacement direction of the mover assembly 30 (e.g., the X direction), and the displacement direction is parallel to the surface of the base 10.
[0042] It should be noted that the arrangement direction mentioned in this disclosure refers to the extension direction of the shortest path of the connecting lines. For example, the arrangement direction of the Hall sensor and the moving magnet refers to the extension direction of the shortest path of the Hall sensor and the moving magnet. The intersection of two directions mentioned in this disclosure means that when the straight lines parallel to these two directions are coplanar, they have an intersection point, that is, the two directions are not parallel.
[0043] See Figure 1In the linear motor provided in this embodiment, the drive coil 20 and the mover assembly 30 are arranged along the Z direction. Specifically, the drive coil 20 may be located between the base 10 and the mover assembly 30, or the mover assembly 30 may be located between the base 10 and the drive coil 20. It should be noted that there is a certain distance between the drive coil 20 and the mover assembly 30, and the projections of the mover magnet 310 and the drive coil 20 in the XOY plane at least partially overlap.
[0044] In some embodiments, a flexible printed circuit board (FPC) is disposed between the base 10 and the vibration module. The flexible printed circuit board (not shown in the figure) is electrically connected to the drive coil 20. The flexible printed circuit board is used to output a drive signal to the drive coil 20, so that the current in the drive coil 20 interacts with the magnetic field of the mover magnet 310 to generate an Ampere force, which drives the mover assembly 30 to produce displacement, thereby generating a vibration effect. The drive signal can be a current signal or a voltage signal.
[0045] In this embodiment, when the drive coil receives a drive signal, the drive coil interacts with the mover magnet to generate an Ampere force, causing the mover assembly to displace. This changes the relative position of the Hall sensor and the mover assembly. The Hall sensor determines the position of the mover assembly in real time based on the magnetic field strength of the mover magnet, thereby determining the displacement of the mover assembly. The Hall sensor and the mover magnet are arranged in an orientation that intersects the displacement direction of the mover assembly, which is parallel to the base surface. Therefore, this embodiment can simultaneously achieve drive vibration and mover assembly displacement detection using both the drive coil and the Hall sensor. Furthermore, due to the small size of the Hall sensor, it can be placed within the internal space of the linear motor, saving internal space and facilitating the stacking of linear motors in electronic devices.
[0046] In some embodiments, the mover assembly 30 may further include a mover 320, which has a groove for mounting the mover magnet 310, i.e., the mover magnet 310 and the mover 320 are embeddedly connected. Therefore, during vibration, the mover magnet 310 and the mover 320 can vibrate synchronously as a whole (mover assembly 30). That is, during vibration, the mover magnet 310 and the mover 320 will not generate friction or collision, nor will they generate noise, which helps to extend the service life of the linear motor. In addition, the mover 310 can be made of a low-density, high-strength material, such as aluminum alloy or carbon fiber.
[0047] In some embodiments, within the limited space of the linear motor, it is necessary to maximize the displacement path of the mover assembly 30, so the Hall sensor is not parallel to the arrangement direction of the mover assembly 30.
[0048] In some embodiments, to avoid the Hall sensor being located inside the mover assembly 30, thus causing it to move together with the mover assembly 30 (i.e., the relative position between the Hall sensor and the mover magnet 310 does not change, which would make it impossible to determine the displacement of the mover assembly 30 based on the magnetic field strength sensed by the Hall sensor), the Hall sensor cannot be located inside the mover assembly 30, nor inside the mover magnet 310 (e.g., between the first magnet 311 and the second magnet 312).
[0049] It is understood that, in the embodiments of this disclosure, the arrangement direction of the Hall sensor and the mover assembly 30 can be any direction other than parallel to the displacement direction. For example, if the displacement direction is the X direction, the arrangement direction of the Hall sensor and the mover assembly 30 can be the Z direction or the Y direction.
[0050] Figure 2 This is a schematic diagram of the magnetic field lines distribution of a moving magnet provided in an embodiment of this disclosure. See also... Figure 2 If the Hall sensor and the mover assembly 30 are arranged along the displacement direction, the distance between them is relatively large to avoid affecting the displacement of the mover assembly 30. Consequently, the magnetic field strength that the Hall sensor can sense in the X, Y, or Z directions is weak, resulting in poor accuracy in determining the displacement of the mover assembly based on changes in magnetic field strength at that location. Therefore, in this embodiment, the arrangement direction of the Hall sensor and the mover assembly 30 intersects the displacement direction.
[0051] In some embodiments, the linear motor further includes a stator assembly and a spring; the stator assembly surrounds the vibration module and the sensing module, and the spring connects the mover assembly and the stator assembly.
[0052] See Figure 1 The stator assembly 40 is connected to the base 10 to form a frame, and the vibration module and sensing module are disposed within this frame. Along the X-direction, springs 51 and 52 are respectively disposed on opposite sides (first side and second side) of the stator assembly 40, wherein springs 51 and 52 are U-shaped. Springs 51 and 52 may include a bottom away from the U-shaped opening and a first portion (near the negative Y-direction) and a second portion (near the positive Y-direction) located on both sides of the U-shaped opening. The first portion of spring 51 is connected to the stator assembly 40 via connector 61, and the second portion of spring 51 is connected to the mover assembly 30 (specifically, mover 320) via connector 62; the first portion of spring 52 is connected to the mover assembly 30 (specifically, mover 320) via connector 63, and the second portion of spring 52 is connected to the stator assembly 40 via connector 64. In this way, the springs can suspend the mover assembly inside the linear motor. In one specific example, the spring and the stator assembly (moving assembly) are welded together by the aforementioned connector to increase the connection strength between the spring and the stator assembly (moving assembly).
[0053] In some embodiments, the frame formed by the base 10 and the stator assembly 40 can serve as the housing of a linear motor. The flexible circuit board on the portion of the base 10 not covered by the stator assembly 40 (i.e., the protruding portion of the base 10) can be electrically connected to an external power source or other devices.
[0054] In some embodiments, a buffer component may be attached to the stator assembly near the inner wall of the spring to reduce the force between the spring (specifically the bottom of the spring) and the stator assembly during vibration, thereby preventing noise during vibration and avoiding damage or deformation caused by collision between the spring and the stator assembly, thus extending the service life of the linear motor and improving its reliability.
[0055] In some embodiments, when the mover assembly is displaced, the vibration effect can be transmitted to the outside of the linear motor by connecting the mover assembly and the stator assembly through a spring. Furthermore, the spring can provide support for the mover assembly after the drive signal disappears, enabling the mover assembly to reset. The spring can also absorb the impact force and vibration energy generated during the movement of the mover assembly, reducing direct collisions between the mover assembly and other components, thereby extending the service life of the linear motor.
[0056] Additionally, the linear motor may include a support assembly located between the spring and the base 10, specifically a first support 71 located between the spring 51 and the base 10, and a second support 72 located between the spring 52 and the base 10. The support assembly provides a certain height to the spring, and since it is coupled to the mover assembly 30 via the spring, it also provides a certain height support to the mover assembly 30, preventing the stability of the spring and mover assembly from being affected by gravity, thus improving the reliability of the linear motor.
[0057] See Figure 1 The linear motor can be equipped with four Hall sensors (Hall_A, Hall_B, Hall_C, and Hall_D). These Hall sensors are connected to a flexible circuit board. The flexible circuit board outputs a drive signal and simultaneously sends a start signal to the Hall sensors, allowing them to promptly detect the magnetic field strength of the moving magnet. When the drive signal disappears (i.e., the flexible circuit board stops outputting the drive signal), the flexible circuit board simultaneously outputs a stop signal to the Hall sensors to turn them off, thus preventing unnecessary power consumption caused by the Hall sensors not turning off in time. Furthermore, Figure 1 Hall_A, Hall_B, Hall_C, and Hall_D are used only to illustrate the location of the Hall sensors in the linear motor and are not intended to limit the number of Hall sensors in the linear motor provided in the embodiments of this disclosure.
[0058] It should be noted that the location of the Hall sensor can be... Figure 1The Hall_A, Hall_B, Hall_C and Hall_D shown are all set in the same position, and the Hall sensor in this embodiment can be a Hall displacement sensor, such as a single-axis Hall displacement sensor or a multi-axis Hall displacement sensor.
[0059] It is understandable that when the Hall sensor is set at Hall_A or Hall_B, the Hall sensor and the moving magnet 310 are arranged in the Y direction; when the Hall sensor is set at Hall_C or Hall_D, the Hall sensor and the moving magnet 310 are arranged in the Z direction.
[0060] In some embodiments, the shape of the flexible circuit board can be changed so that the flexible circuit board is electrically connected to the Hall sensor.
[0061] See Figure 1 Hall_A can be set in the positive Y direction of the mover magnet 310, and Hall_B can be set in the negative Y direction of the mover magnet 310, that is, Hall_A, the mover magnet 310 and Hall_B are arranged sequentially along the Y direction. In some embodiments, along the first direction (Z direction), the sensing position of the Hall sensor is lower than the top of the mover assembly 30 and higher than the bottom of the mover assembly 30.
[0062] In some embodiments, the Hall sensor and the mover assembly are arranged along a second direction (Y direction), which is perpendicular to the base surface and intersects the displacement direction (X direction). Meanwhile, along the Z direction, compared to the case where the sensing position of the Hall sensor is above the top or below the bottom of the mover assembly 30, when the sensing position of the Hall sensor is below the top and above the bottom of the mover assembly 30, the rate of change of the magnetic field strength sensed by the Hall sensor with the displacement is faster and less affected by the drive coil, thus achieving higher accuracy.
[0063] In some embodiments, the mover magnet 310 includes a first magnet 311 and a second magnet 312 arranged along the displacement direction. Both the first magnet 311 and the second magnet 312 have north and south magnetic poles. The north and south magnetic pole directions of the first magnet 311 and the second magnet 312 are opposite and parallel to the first direction. It should be noted that the magnets involved in this disclosure are bipolar magnets.
[0064] See Figure 1 The moving magnet 310 includes a first magnet 311 and a second magnet 312 arranged along the X direction. The magnetic pole direction of the first magnet 311 from the S pole to the N pole can be the positive Z direction, and the magnetic pole direction of the second magnet 312 from the S pole to the N pole can be the negative Z direction. It should be noted that the north and south magnetic pole directions refer to the arrangement direction of the S pole and the N pole.
[0065] In some embodiments, the first magnet 311 and the second magnet 312 are the same size, and the projections of the first magnet 311 and the second magnet 312 onto the YOZ plane overlap.
[0066] In some embodiments, along the first direction, the sensing position of the Hall sensor is at the same height as the north-south pole junction of the first magnet 311 and the north-south pole junction of the second magnet 312.
[0067] Figure 3 This is a schematic diagram showing the relative positions of the Hall sensor and the mover magnet according to an embodiment of this disclosure. Figure 4 for Figure 3 The diagram illustrates the relationship between the magnetic field strength of the mover magnet sensed by the Hall sensor and the displacement of the mover assembly. (See also...) Figure 3 and Figure 4 The sensing positions P of Hall_A and Hall_B are at the same height in the Z direction as the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312. When the mover assembly displaces along the X direction, at the sensing position P of Hall_A or Hall_B, the magnetic field of the mover magnet 310 in the X direction and the magnetic field in the Y direction are weak and irregular, while the magnetic field strength in the Z direction is strong and has a certain mapping relationship with the displacement of the mover assembly.
[0068] In some embodiments, Hall_A and Hall_B are at the same height in the Z direction as the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312. As the displacement of the mover assembly in the X direction changes, the change in magnetic field strength of the mover magnet 310 in the Z direction tends to be linear. It can be understood that when the sensing positions P of Hall_A and Hall_B are at the same height in the Z direction as the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312, the displacement of the mover assembly can be determined by sensing the change in magnetic field strength of the mover magnet 310 in the Z direction.
[0069] In one specific embodiment, such as Figure 3 and Figure 4As shown, the sensing position P of Hall_A / Hall_B is at the same height as the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312 in the Z direction. When the linear motor is not started, on the XOZ plane, when the distance between the sensing position P of Hall_A (or Hall_B) and the first magnet 311 is the same as the distance between the sensing position P of Hall_A (or Hall_B) and the second magnet 312, as the displacement of the mover assembly in the X direction changes, the change in the magnetic field strength of the mover magnet 310 in the Z direction tends to be linear and symmetrical about the zero point center.
[0070] In another specific embodiment, the sensing position P of Hall_A / Hall_B is at the same height in the Z direction as the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312. When the linear motor is not started, on the XOZ plane, when the distance between the sensing position P of Hall_A (or Hall_B) and the first magnet 311 is different from the distance between the sensing position P of Hall_A (or Hall_B) and the second magnet 312, as the displacement of the mover assembly in the X direction changes, the magnetic field strength of the mover magnet 310 in the Z direction tends to change linearly and is centrally symmetrical about a point on the horizontal axis except for the zero point.
[0071] In some embodiments, along the first direction, the sensing position of the Hall sensor is at a different height than the north-south pole junction of the first magnet 311 and the north-south pole junction of the second magnet 312. Figure 5 This is a schematic diagram showing the relative positions of the Hall sensor and the mover magnet according to another embodiment of this disclosure. Figure 6 for Figure 5 The diagram illustrates the relationship between the magnetic field strength of the mover magnet sensed by the Hall sensor and the displacement of the mover assembly. (Assembly 1 and...) Figure 5 Along the Z direction, the sensing position P of Hall_A / Hall_B can be higher or lower than the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312.
[0072] See Figure 5 and Figure 6 When the moving component 30 is displaced along the X direction, at the sensing position P of Hall_A or Hall_B, the magnetic field strength of the moving magnet 310 in the X direction, the magnetic field strength in the Y direction, and the magnetic field strength in the Z direction are relatively strong and have a certain mapping relationship with the displacement of the moving component.
[0073] In some embodiments, along the Z direction, when the sensing position P of Hall_A or Hall_B is above or below the north-south pole boundary line AA of the first magnet 311 and the second magnet 312, as the displacement of the mover assembly 30 in the X direction changes, the changes in the magnetic field strength of the mover magnet 310 in the Y direction and in the Z direction tend to be linear, while the change in the magnetic field strength of the mover magnet 310 in the X direction is approximately axially symmetric about a straight line parallel to the longitudinal axis. Therefore, along the Z direction, when the sensing positions P of Hall_A and Hall_B are above or below the north-south pole boundary line AA of the first magnet 311 and the second magnet 312, the displacement of the mover assembly can be determined by sensing the change in the magnetic field strength of the mover magnet 310 in the Y direction and / or in the Z direction.
[0074] In one specific embodiment, such as Figure 6 As shown, along the Z direction, the sensing position P of Hall_A / Hall_B is higher or lower than the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312. When the linear motor is not started, on the XOZ plane, when the distance between the sensing position P of Hall_A (or Hall_B) and the first magnet 311 is the same as the distance between the sensing position P of Hall_A (or Hall_B) and the second magnet 312, as the displacement of the mover assembly 30 in the X direction changes, the magnetic field strength of the mover magnet 310 in the Y direction and the magnetic field strength in the Z direction tend to change linearly and are symmetrical about the zero point center.
[0075] In one specific embodiment, such as Figure 6 As shown, along the Z direction, the sensing position P of Hall_A / Hall_B is higher or lower than the north-south pole boundary line AA of the first magnet 311 and the north-south pole boundary line AA of the second magnet 312. When the linear motor is not started, on the XOZ plane, when the distance between the sensing position P of Hall_A (or Hall_B) and the first magnet 311 is different from the distance between the sensing position P of Hall_A (or Hall_B) and the second magnet 312, as the displacement of the mover assembly 30 in the X direction changes, the magnetic field strength of the mover magnet 310 in the Y direction and the magnetic field strength in the Z direction tend to be linear and centrally symmetrical about a point on the horizontal axis except for the zero point.
[0076] It should be noted that the embodiments disclosed herein do not impose any limitations on the size or shape of the Hall sensor. For example, the size L of the Hall sensor in the X direction can be greater than, less than, or equal to the distance between the first magnet 311 and the second magnet 312; the size W of the Hall sensor in the Z direction can be greater than, less than, or equal to half the size of the first magnet 311 (second magnet 312) in the Z direction.
[0077] In some embodiments, along the first direction (Z direction), the projection of the Hall sensor overlaps with the projection of the mover assembly 30 on the base 10.
[0078] Figure 7 This is a schematic diagram showing the relative positions of a Hall sensor and a moving magnet according to an embodiment of this disclosure. Figure 8 for Figure 7 The diagram illustrates the relationship between the magnetic field strength of the mover magnet sensed by the Hall sensor and the displacement of the mover assembly. (Combined with...) Figure 1 , Figure 7 and Figure 8 Hall_C can be set in the positive Z direction of the moving component 30, and Hall_D can be set in the negative Z direction of the moving component 30. That is, Hall_C, the moving component 30 and Hall_D are arranged in sequence along the Z direction.
[0079] In some embodiments, along a first direction, the Hall sensor and the drive coil 20 are located on opposite sides of the mover assembly 30.
[0080] See Figure 1 , Figure 7 and Figure 8 Hall_C and drive coil 20 are respectively positioned in the positive Z direction and negative Z direction of the mover assembly 30.
[0081] In some embodiments, the Hall sensor and the drive coil 20 are located on the same side of the mover assembly 30 along a first direction.
[0082] See Figure 1 , Figure 7 and Figure 8 Hall_D and drive coil 20 are positioned in the negative Z direction of the mover assembly 30, and Hall_D and drive coil 20 are connected to the flexible circuit board.
[0083] In some embodiments, when the projections of Hall_C / Hall_D overlap with the projection of the mover assembly 30 along the Z direction, the change in the magnetic field strength of the mover magnet 310 in the Z direction tends to be linear as the displacement of the mover assembly 30 in the X direction changes. Therefore, the displacement of the mover assembly 30 can be determined by sensing the change in the magnetic field strength of the mover magnet 310 in the Z direction.
[0084] In a specific example, along the Z direction, the projections of Hall_C / Hall_D overlap with the projection of the mover assembly 30. When the linear motor is not started, on the XOZ plane, when the distance between the sensing position P of Hall_C (or Hall_D) and the first magnet 311 is the same as the distance between the sensing position P of Hall_C (or Hall_D) and the second magnet 312, as the displacement of the mover assembly 30 in the X direction changes, the change in the magnetic field strength of the mover magnet 310 in the Z direction tends to be linear and symmetrical about the zero point center.
[0085] In another specific example, along the Z direction, the projections of Hall_C / Hall_D overlap with the projection of the mover assembly 30. When the linear motor is not started, on the XOZ plane, when the distance between the sensing position P of Hall_C (or Hall_D) and the first magnet 311 is the same as the distance between the sensing position P of Hall_C (or Hall_D) and the second magnet 312, as the displacement of the mover assembly 30 in the X direction changes, the change in the magnetic field strength of the mover magnet 310 in the Z direction is close to a linear change and is centrally symmetrical about a point on the horizontal axis except for the zero point.
[0086] Preferably, in order to reduce the size of the linear motor in the Z direction and avoid the magnetic field generated by the drive coil 20 affecting the change in the magnetic field strength of the mover magnet 310, thereby affecting the measurement accuracy of the Hall sensor, a Hall sensor (e.g., a sensor whose sensing position is below the top of the mover assembly 30 and above the bottom of the mover assembly 30) can be provided in the linear motor. Figure 1 , Figure 3 as well as Figure 5 Hall_A and / or Hall_B as shown), instead of setting Hall sensors (e.g., Hall_A and / or Hall_B) in the linear motor that overlap with the projection of the mover assembly 30 in the first direction. Figure 1 as well as Figure 7 Hall_C and Hall_D are shown.
[0087] Figure 9 This is a schematic diagram of the structure of an electronic device provided for a disclosed embodiment. See also... Figure 9 The electronic device includes a linear motor 100 as described in any of the above embodiments and a drive module 200; the drive module 200 is connected to the linear motor 100, the drive module 200 is configured to provide a drive signal to the linear motor 100, and to receive the displacement of the mover assembly output by the sensing module; the drive module 200 is also configured to adjust the drive signal according to the displacement to adjust the amplitude of the vibration module.
[0088] See Figure 9The drive module 200 can be connected to the drive coil and the sensing module via a flexible circuit board. The drive module 200 can transmit drive signals to the drive coil via the flexible circuit board to drive the actuator assembly to generate displacement.
[0089] In some embodiments, the drive module 200 may store the displacement of the moving component corresponding to the preset amplitude. The drive module 200 can adjust the drive signal (amplitude and / or direction of voltage or current signal) according to the displacement of the moving component output by the sensing module until the displacement of the moving component is the same as the displacement of the moving component corresponding to the preset amplitude. At this time, the amplitude of the vibration module is also the same as the preset amplitude, which can improve the user's tactile experience.
[0090] It should be noted that the description of the above electronic device is similar to the description of the linear motor embodiment described above, and has similar beneficial effects as the linear motor embodiment. For technical details not disclosed in the embodiments of the electronic device of this disclosure, please refer to the description of the linear motor embodiment of this disclosure for understanding.
[0091] This disclosure provides a linear motor and an electronic device. The linear motor includes a base, and a vibration module and a sensing module disposed above the base. The vibration module includes a drive coil and a mover assembly arranged along a first direction. The mover assembly includes a mover magnet, and the first direction is perpendicular to the surface of the base. The sensing module includes at least one Hall sensor configured to obtain the position of the mover assembly of the drive coil based on the magnetic field strength of the mover magnet, thereby determining the displacement of the mover assembly. The arrangement direction of the Hall sensor and the mover magnet intersects with the displacement direction of the mover assembly, and the first direction is perpendicular to the displacement direction.
[0092] In this embodiment, when the drive coil receives a drive signal, the drive coil interacts with the mover magnet to generate an Ampere force, causing the mover assembly to displace. This changes the relative position of the Hall sensor and the mover assembly. The Hall sensor determines the position of the mover assembly in real time based on the magnetic field strength of the mover magnet, thereby determining the displacement of the mover assembly. Therefore, this embodiment can simultaneously achieve drive vibration and mover assembly displacement detection using both the drive coil and the Hall sensor. Furthermore, due to the small size of the Hall sensor, it can be installed within the internal space of the linear motor, saving internal space and facilitating the stacking of linear motors in electronic devices.
[0093] It should be understood that the phrase "an embodiment" or "one embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this disclosure. Therefore, "in one embodiment" or "one embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this disclosure, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this disclosure. The sequence numbers of the above-described embodiments are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.
[0094] The above description is merely a preferred embodiment of this disclosure and does not limit the patent scope of this disclosure. Any equivalent structural transformations made using the contents of this specification and drawings under the inventive concept of this disclosure, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this disclosure.
Claims
1. A linear motor, characterized in that, include: A base, and a vibration module and a sensing module disposed on the base; The vibration module includes a drive coil and a mover assembly arranged along a first direction, the mover assembly including a mover magnet, and the first direction being perpendicular to the surface of the base; The sensing module includes at least one Hall sensor, which is configured to determine the displacement of the moving part assembly based on the magnetic field strength of the moving part magnet; wherein the arrangement direction of the Hall sensor and the moving part magnet intersects with the displacement direction of the moving part assembly, and the displacement direction is parallel to the surface of the base.
2. The linear motor according to claim 1, characterized in that, Along the first direction, the sensing position of the Hall sensor is below the top of the actuator assembly and above the bottom of the actuator assembly.
3. The linear motor according to claim 2, characterized in that, The moving magnet includes a first magnet and a second magnet arranged along the displacement direction, and both the first magnet and the second magnet include north and south magnetic poles; The north-south magnetic poles of the first magnet are opposite to and parallel to the north-south magnetic poles of the second magnet.
4. The linear motor according to claim 3, characterized in that, Along the first direction, the sensing position of the Hall sensor is at the same height as the north-south pole junction of the first magnet and the north-south pole junction of the second magnet.
5. The linear motor according to claim 3, characterized in that, Along the first direction, the sensing position of the Hall sensor is at a different height from the north-south pole junction of the first magnet and the north-south pole junction of the second magnet.
6. The linear motor according to claim 1, characterized in that, The projection of the Hall sensor on the base overlaps with the projection of the moving part assembly on the base.
7. The linear motor according to claim 6, characterized in that, Along the first direction, the Hall sensor and the drive coil are located on opposite sides of the mover assembly.
8. The linear motor according to claim 6, characterized in that, Along the first direction, the Hall sensor and the drive coil are located on the same side of the mover assembly.
9. The linear motor according to claim 1, characterized in that, It also includes the stator assembly and springs; The stator assembly surrounds the vibration module and the sensing module, and the spring connects the mover assembly and the stator assembly.
10. An electronic device, characterized in that, Includes the linear motor and drive module as described in any one of claims 1 to 9; The drive module is connected to the linear motor, and the drive module is configured to provide a drive signal to the linear motor and receive the displacement of the actuator component output by the sensing module. The drive module is also configured to adjust the drive signal according to the displacement to adjust the amplitude of the vibration module.