Piezoelectric motor and electronic device

Abstract

The application provides a piezoelectric motor and an electronic device, the piezoelectric motor comprising: a shell; an elastic recovery component, a circumferential side of the elastic recovery component being fixed on an inner wall of the shell; a first piezoelectric sheet, the first piezoelectric sheet being attached to the elastic recovery component, the first piezoelectric sheet being in a spiral shape; when the first piezoelectric sheet is in an energized state, the elastic recovery component can reciprocate along an axial direction of the shell, and the first piezoelectric sheet is stretched along the axial direction of the shell. The piezoelectric motor is improved, so that the piezoelectric motor has more functions, the volume of the piezoelectric motor can be controlled from increasing too much, and the effect of miniaturization of the electronic device is further achieved.

Description

Technical Field

[0001] This application belongs to the field of motor technology, specifically, it relates to a piezoelectric motor and electronic device. Background Technology

[0002] With the continuous development of science and technology and modern industry, motors are being used in an increasingly wide range of applications. While traditional electromagnetic motors offer high speed and power, their reliance on the electromagnetic force between the rotor magnet and stator coils to drive the rotor results in a complex structure and vulnerability to electromagnetic interference. Therefore, piezoelectric motors, due to their fast response, simple structure, and immunity to electromagnetic interference, have gradually gained widespread attention.

[0003] The vibration of a piezoelectric motor is caused by the expansion and contraction of a piezoelectric ceramic when an electric current is applied, which deforms the elastic sheet and drives the mass block to move and generate vibration. Due to its non-magnetic nature, simple structure, flexible size design, extremely short response time, high energy efficiency, and much smaller size than rotor motors and electromagnetic linear motors, piezoelectric motors can provide the most complex and delicate tactile feedback experience and are widely used in various electronic devices.

[0004] However, with the advancement of technology, the size of electronic components such as camera modules in electronic devices is getting larger and larger. At the same time, if the size of electronic devices continues to increase, it will greatly affect the user's grip. If the size of the vibration motor is further miniaturized, it will easily lead to a reduction in the vibration amplitude and intensity of the piezoelectric motor, making it impossible to achieve the expected vibration effect.

[0005] Therefore, it is necessary to improve the structure of piezoelectric motors to solve the problem of reduced vibration amplitude and intensity of piezoelectric motors in the process of miniaturization of piezoelectric motors in the prior art. Summary of the Invention

[0006] The purpose of this application is to provide a piezoelectric motor and electronic device to solve the problem of reduced vibration amplitude and intensity of piezoelectric motors in the process of miniaturizing piezoelectric motors in the prior art.

[0007] In a first aspect, this application provides a piezoelectric motor, comprising:

[0008] shell;

[0009] An elastic recovery member, the periphery of which is fixed to the inner wall of the outer casing;

[0010] A first piezoelectric element is attached to the elastic recovery member, and the first piezoelectric element is spiral-shaped.

[0011] When the first piezoelectric element is energized, the elastic recovery member can reciprocate along the axial direction of the outer shell, and the first piezoelectric element is stretched along the axial direction of the outer shell.

[0012] Optionally, the elastic recovery element includes an elastic substrate and a mass block. The periphery of the elastic substrate is fixed to the inner wall of the housing. The first piezoelectric sheet and the mass block are respectively fixed to both sides of the elastic substrate. The elastic substrate can be stretched along the axial direction of the housing.

[0013] Optionally, the elastic substrate is helical, and the elastic substrate has the same shape and size as the first piezoelectric sheet, and the first piezoelectric sheet and the elastic substrate can be stretched along the axial direction of the housing.

[0014] Optionally, the elastic substrate has a first end and a second end, the first end and the second end being fixed to the inner wall of the housing.

[0015] Optionally, a second piezoelectric sheet is disposed between the elastic substrate and the mass block, and the second piezoelectric sheet is fixed on the elastic substrate on the side opposite to the first piezoelectric sheet.

[0016] Optionally, an opening is provided at the center of the elastic substrate, and a boss is provided on the side of the mass block facing the elastic substrate, the boss being inserted into and fixed in the opening.

[0017] Optionally, the housing has a through hole, and a circuit board is disposed in the through hole, with the first piezoelectric sheet electrically connected to the circuit board.

[0018] Optionally, the first piezoelectric element has a multilayer bicrystalline structure.

[0019] Secondly, this application provides an electronic device in which any of the piezoelectric motors described above are disposed.

[0020] Optionally, the outer casing has a through hole, and a circuit board is disposed in the through hole, wherein the first piezoelectric sheet is electrically connected to the circuit board;

[0021] The electronic device contains a motherboard, and the circuit board is electrically connected to the motherboard.

[0022] This application improves the piezoelectric motor, enabling it to have more functions while controlling its size to not increase excessively, thus further achieving the miniaturization of electronic devices.

[0023] Other features and advantages of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present application and, together with their description, serve to explain the principles of the present application.

[0025] Figure 1 This is a schematic diagram of the structure of a piezoelectric motor provided in a specific embodiment of this application;

[0026] Figure 2 This is one of the structural schematic diagrams and disassembly diagrams of a piezoelectric motor provided in the specific embodiments of this application;

[0027] Figure label:

[0028] 1. Outer shell; 11. Base; 12. Cover; 13. Through hole; 2. Elastic recovery component; 21. Elastic substrate; 211. First end; 212. Second end; 213. Opening; 22. Mass block; 221. Boss; 3. First piezoelectric sheet; 4. Circuit board. Detailed Implementation

[0029] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0030] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0031] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0032] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0034] Firstly, such as Figure 1 and Figure 2 As shown, this application provides a piezoelectric motor, comprising:

[0035] The outer casing 1 serves as the outer structure of the piezoelectric motor, protecting the internal elastic recovery element 2 and the first piezoelectric sheet 3, and also facilitating installation inside electronic devices. In this embodiment, the outer casing 1 is cylindrical. The shape of the outer casing 1 can be adjusted according to actual usage requirements and is not specifically limited here.

[0036] The outer casing 1 can be configured as a split structure, comprising a base 11 and a cover 12. The base 11 is a cylindrical cavity structure, and the cover 12 can be fastened to the base 11. The split design of the outer casing 1 reduces the difficulty of manufacturing the piezoelectric motor and also simplifies subsequent maintenance. The outer casing 1 and cover 12 can be made of 301 stainless steel or other metal materials; any material that can protect the internal structure without affecting the normal operation of the piezoelectric motor is acceptable.

[0037] The elastic recovery member 2 is fixed to the inner wall of the outer shell 1. When the elastic recovery member 2 is subjected to force, it can move in the axial direction of the outer shell 1. As the elastic recovery member 2 shakes in the outer shell 1, the vibration of the piezoelectric motor can be realized.

[0038] The first piezoelectric element 3 is attached to the elastic recovery element 2 and is spiral-shaped. The first piezoelectric element 3 possesses spontaneous polarization properties, which can be transformed under the influence of an external electric field. Therefore, when an external electric field is applied to a piezoelectric dielectric, the first piezoelectric element 3 will deform. However, the reason for this deformation is that applying an external electric field identical to the spontaneous polarization effectively enhances the polarization intensity. This increased polarization intensity causes the first piezoelectric element 3 to elongate along the polarization direction. Conversely, if a reverse electric field is applied, the ceramic element will shorten along the polarization direction. This phenomenon, where an electrical effect transforms into a mechanical effect, is called the inverse piezoelectric effect.

[0039] When the first piezoelectric element 3 is energized, the elastic recovery member 2 can reciprocate along the axial direction of the outer shell 1, and the first piezoelectric element 3 is stretched along the axial direction of the outer shell 1. When the spiral-shaped first piezoelectric element 3 deforms, it elongates along the axial direction of the outer shell 1. The sheet-like first piezoelectric element 3 has a very small volume, which allows for further reduction in the size of the piezoelectric motor. Simultaneously, the spiral-shaped first piezoelectric element 3 can be stretched, thereby forming a longer vibration period, which in turn ensures the vibration intensity of the piezoelectric motor.

[0040] Specifically, the initial position of the elastic reset member is set when the first piezoelectric element 3 is not energized. When energized, the first piezoelectric element 3 deforms, and this deformation drives the elastic reset member to move axially within the outer casing 1. Since the first piezoelectric element 3 is helical, its deformation force acts on the elastic reset member, causing it to pull the first piezoelectric element 3 axially, thus unfolding the helical structure. As the deformation and frequency of the first piezoelectric element 3 increase, the displacement amplitude of the elastic reset member gradually increases, enabling it to reciprocate within the outer casing 1, achieving high-frequency and large-amplitude vibration. This achieves miniaturization of the piezoelectric motor while simultaneously increasing its vibration frequency and amplitude. Taking the installation of the piezoelectric motor in a mobile phone as an example, it not only provides more installation space for other electronic devices but also allows users to clearly feel the vibration of the phone when the piezoelectric motor vibrates, effectively serving as a reminder.

[0041] Optionally, the elastic recovery component 2 includes an elastic substrate 21 and a mass block 22. The periphery of the elastic substrate 21 is fixed to the inner wall of the outer shell 1. The first piezoelectric sheet 3 and the mass block 22 are respectively fixed to both sides of the elastic substrate 21. The elastic substrate 21 can be stretched along the axial direction of the outer shell 1. When the first piezoelectric sheet 3 is energized, the deformation generated by the first piezoelectric sheet 3 acts on the elastic substrate 21, and the elastic substrate 21 is stretched along the axial direction within the outer shell 1. As the elastic substrate 21 is stretched, it moves away from its initial position. At the same time, the elastic force of the elastic substrate 21 itself will cause it to be subjected to a force in the direction of its initial position. At this time, the mass block 22 can further increase the displacement distance of the elastic substrate 21, allowing it to have a larger displacement during reciprocating motion, thereby achieving the effect of increasing the vibration of the piezoelectric motor.

[0042] Specifically, the mass block 22 is preferably a tungsten-nickel alloy. Tungsten-nickel alloy has extremely high density, allowing it to have a large weight in a small volume. Utilizing the weight of the mass block 22 itself, when the elastic substrate 21 moves in the first direction, it pushes the mass block 22 to move in the first direction as well. When the deformation of the first piezoelectric sheet 3 is insufficient to push the elastic substrate 21 to continue moving in the first direction, if there is no fixed mass block 22 on the elastic substrate 21, the elastic substrate 21 will move back to its initial position under the action of its own elastic restoring force. In this embodiment, the mass block 22, due to its large weight, generates significant inertia, causing the elastic substrate 21 to continue moving in the first direction, further increasing the amplitude and vibration of the piezoelectric motor. Other materials with high density can also be used; no specific limitation is made here.

[0043] Optionally, the elastic substrate 21 is helical, and the elastic substrate 21 has the same shape and size as the first piezoelectric sheet 3. The first piezoelectric sheet 3 and the elastic substrate 21 can be stretched along the axial direction of the outer shell 1. Since the elastic electrode and the first piezoelectric sheet 3 have the same helical structure, when the first piezoelectric sheet 3 is energized, the deformation of the first piezoelectric sheet 3 causes the elastic substrate 21 to displace axially within the outer shell 1. The helical structure greatly increases the displacement of the first piezoelectric sheet 3 and the elastic substrate 21. Simultaneously, the force exerted on the elastic substrate 21 by the mass block 22 further increases the displacement of the elastic substrate 21 during reciprocating motion, thereby increasing the vibration amplitude of the piezoelectric motor.

[0044] Optionally, the elastic substrate 21 has a first end 211 and a second end 212, which are fixed to the inner wall of the outer casing 1. The spiral-shaped elastic substrate 21 has two ends arranged opposite each other. By fixing the first end 211 and the second end 212 to the inner wall of the outer casing 1, when the first piezoelectric sheet 3 is energized, the first piezoelectric sheet 3 and the elastic substrate 21 move away from their initial positions. Meanwhile, the first end 211 and the second end 212 are fixed to the inner wall of the outer casing 1, causing the regions of the first piezoelectric sheet 3 and the elastic substrate 21 near the axis of the outer casing 1 to move away from their initial positions. Simultaneously, utilizing the spiral structure of the elastic substrate 21 and the first piezoelectric sheet 3, the amplitude can be increased while miniaturizing the outer casing 1, thereby improving the vibration of the piezoelectric motor.

[0045] Specifically, the first end 211 and the second end 212 can be inserted into the mounting groove by opening a mounting groove on the inner wall of the base 11 and fixed by welding or other means.

[0046] Optionally, a second piezoelectric sheet is disposed between the elastic substrate 21 and the mass block 22. The second piezoelectric sheet is fixed on the elastic substrate 21 on the side opposite to the first piezoelectric sheet 3. The first piezoelectric sheet 3 and the second piezoelectric sheet are respectively disposed on both sides of the elastic substrate 21. By disposing of two piezoelectric sheets on both sides of the elastic substrate 21, a push-pull drive can be realized, further improving the vibration frequency and vibration intensity of the piezoelectric motor.

[0047] Optionally, an opening 213 is provided at the center of the elastic substrate 21, and a boss 221 is provided on the side of the mass block 22 facing the elastic substrate 21. The boss 221 is inserted into and fixed in the opening 213. The opening 213 in the central region of the elastic substrate 21 allows for pre-fixation between the elastic substrate 21 and the mass block 22 by inserting the boss 221 into the opening 213. To strengthen the connection between the elastic substrate 21 and the mass block 22, laser welding or other methods can be used to fix the boss 221 and the opening 213, effectively increasing the connection strength between them. When the piezoelectric motor starts working, even if the mass block 22 pulls the elastic substrate 21 by inertia, it will not cause separation between the mass block 22 and the elastic substrate 21, extending the service life of the piezoelectric motor.

[0048] Optionally, the outer casing 1 has a through hole 13, and a circuit board 4 is disposed in the through hole 13. The first piezoelectric sheet 3 is electrically connected to the circuit board 4. The circuit board 4 can preferably be a flexible circuit board 4. The first piezoelectric sheet 3 can be bonded to the circuit board 4 by means of materials such as solder paste, silver paste or anisotropic conductive film, or by means of solder wire, etc., without specific limitation.

[0049] Optionally, the first piezoelectric element 3 has a multilayer bicrystalline structure. The multilayer bicrystalline structure can ensure that the volume of the first piezoelectric element 3 is reduced while maintaining a large deformation, thereby ensuring that it can drive the elastic substrate 21 to move within the outer shell 1, thus achieving the effect of increasing the vibration amplitude.

[0050] Specifically, the first piezoelectric element 3 and the elastic substrate 21 are sheet-like structures when not energized or under stress. The spiral-shaped first piezoelectric element 3 and elastic substrate 21 are formed by bending strip structures, and these strip structures are called spiral arms. With the inner diameter of the outer shell 1 remaining constant, the structural strength and tensile length of the first piezoelectric element 3 and elastic substrate 21 can be adjusted by changing the width of the spiral arm. As the width of the spiral arm gradually increases, the structural strength of the first piezoelectric element 3 and elastic substrate 21 becomes stronger, while the tensile length decreases, resulting in a corresponding decrease in the amplitude and vibration of the piezoelectric motor. Conversely, as the width of the spiral arm gradually decreases, the structural strength of the first piezoelectric element 3 and elastic substrate 21 becomes weaker, while the tensile length increases, resulting in a corresponding increase in the amplitude and vibration of the piezoelectric motor.

[0051] Secondly, this application provides an electronic device in which a piezoelectric motor as described in any of the above embodiments is disposed. Installing a piezoelectric motor as described in the above embodiments in the electronic device enables the electronic device to have a greater vibration amplitude and frequency when providing vibration alerts, thus providing a better user experience.

[0052] Optionally, the outer casing 1 has a through hole 13, and a circuit board 4 is disposed within the through hole 13. The first piezoelectric element 3 is electrically connected to the circuit board 4. The electronic device contains a motherboard, and the circuit board 4 is electrically connected to the motherboard. By connecting the motherboard to the first piezoelectric element 3, the control system of the electronic device can control the power supply to the first piezoelectric element 3. The motherboard can select the direction of the current and the voltage level, thereby enabling the electronic device to achieve a vibration alert effect.

[0053] This application improves the piezoelectric motor, enabling it to have more functions while controlling its size to not increase excessively, thus further achieving the miniaturization of electronic devices.

[0054] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A piezoelectric motor, characterized in that, include: shell; An elastic recovery member, the periphery of which is fixed to the inner wall of the outer casing; A first piezoelectric element is attached to the elastic recovery member, and the first piezoelectric element is spiral-shaped. When the first piezoelectric element is energized, the elastic recovery member can reciprocate along the axial direction of the outer shell, and the first piezoelectric element is stretched along the axial direction of the outer shell. The elastic recovery component includes an elastic substrate and a mass block. The periphery of the elastic substrate is fixed to the inner wall of the outer shell. The first piezoelectric sheet and the mass block are respectively fixed to both sides of the elastic substrate. The elastic substrate can be stretched along the axial direction of the outer shell.

2. The piezoelectric motor according to claim 1, characterized in that, The elastic substrate is spiral-shaped and has the same shape and size as the first piezoelectric sheet. The first piezoelectric sheet and the elastic substrate can be stretched along the axial direction of the housing.

3. The piezoelectric motor according to claim 2, characterized in that, The elastic substrate has a first end and a second end, which are fixed to the inner wall of the outer shell.

4. The piezoelectric motor according to claim 1, characterized in that, A second piezoelectric sheet is disposed between the elastic substrate and the mass block, and the second piezoelectric sheet is fixed on the elastic substrate on the side opposite to the first piezoelectric sheet.

5. The piezoelectric motor according to claim 1, characterized in that, An opening is provided at the center of the elastic substrate, and a boss is provided on the side of the mass block facing the elastic substrate. The boss is inserted into and fixed in the opening.

6. The piezoelectric motor according to claim 1, characterized in that, The outer casing has a through hole, and a circuit board is disposed in the through hole. The first piezoelectric sheet is electrically connected to the circuit board.

7. The piezoelectric motor according to claim 1, characterized in that, The first piezoelectric element has a multilayer bicrystalline structure.

8. An electronic device, characterized in that, The electronic device is equipped with a piezoelectric motor as described in any one of claims 1-7.

9. The electronic device according to claim 8, characterized in that, The outer casing has a through hole, and a circuit board is disposed in the through hole. The first piezoelectric piece is electrically connected to the circuit board. The electronic device contains a motherboard, and the circuit board is electrically connected to the motherboard.

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