Piezoelectric actuators, piezoelectric motors, cameras, and electronic devices

Abstract

This application provides a piezoelectric actuator, a piezoelectric motor, a camera, and an electronic device. Centered on an isolation layer, an inner signal electrode layer, a piezoelectric ceramic layer, and an inner ground electrode are stacked on either side from near to far. Each inner signal electrode layer includes four inner signal electrodes, each corresponding to and electrically connected to an outer signal electrode. This forms eight piezoelectric zones corresponding to each inner signal electrode. These eight piezoelectric zones, arranged in this way, provide significant driving force with a relatively simple structure and small size, enabling a wide range of motion modes and thus achieving good optical image stabilization. The piezoelectric motor based on this piezoelectric actuator, with its relatively simple structure and small size, can achieve powerful macroscopic motion of the driven component, thereby meeting the miniaturization requirements of the camera and electronic device, and enabling the camera and electronic device to possess corresponding beneficial effects.

Description

Technical Field

[0001] This utility model relates to the field of piezoelectric drive, and more particularly to piezoelectric actuators, piezoelectric motors, cameras, and electronic devices. Background Technology

[0002] Piezoelectric actuators utilize the inverse piezoelectric effect of piezoelectric materials (applying an electric field along the polarization direction causes deformation in a specific direction; applying an electric field in the opposite direction reverses the direction of deformation, and the deformation returns to normal after the electric field is removed), exciting the vibration modes at characteristic frequencies to produce resonance. Piezoelectric motors, based on piezoelectric actuators, can convert microscopic vibrations into macroscopic motion of the driven component, thereby driving the target structural assembly to change position and achieving precise position control.

[0003] The piezoelectric motor-driven cameras provided by related technologies face problems such as large size, complex structure, insufficient driving force, and limited movement modes, resulting in poor performance in achieving optical image stabilization. Utility Model Content

[0004] This invention provides a piezoelectric actuator, a piezoelectric motor, a camera, and electronic devices, which can provide a large driving force with a relatively simple structure and small size to achieve a variety of motion modes, thereby achieving good optical image stabilization.

[0005] In a first aspect, the present invention provides a piezoelectric actuator, which includes: a piezoelectric actuator, characterized in that it includes: a drive head and a piezoelectric body;

[0006] The piezoelectric body includes an isolation layer, two inner grounding electrodes, two piezoelectric ceramic layers, two inner signal electrode layers, multiple outer signal electrodes, and an outer grounding electrode.

[0007] On each side of the isolation layer, from near to far, there is an inner signal electrode layer, a piezoelectric ceramic layer and an inner ground electrode stacked;

[0008] Each inner signal electrode layer includes four inner signal electrodes, and each inner signal electrode corresponds to an outer signal electrode and is electrically connected to it.

[0009] All internal grounding electrodes are electrically connected to the external grounding electrode;

[0010] The drive head is located on the piezoelectric body, parallel to both sides of the insulating layer.

[0011] In a second aspect, the present invention provides a piezoelectric motor, which includes a motor housing, motor balls, driven components, a bracket, and a piezoelectric actuator as described in the first aspect.

[0012] The piezoelectric actuator is fixed to the bracket, which is connected to the inner wall of the motor housing;

[0013] The drive head of the piezoelectric actuator abuts against the driven component, and the motor balls are disposed between the driven component and the inner wall of the motor housing.

[0014] Thirdly, this utility model provides a camera, which includes an optical module, a camera housing, a camera ball, and a piezoelectric actuator as described in the first aspect;

[0015] The optical module is movably connected to the camera housing via a camera ball bearing;

[0016] The piezoelectric actuator is positioned between the camera housing and the optical module to drive relative movement between the optical module and the camera housing.

[0017] Fourthly, this utility model provides an electronic device, which includes a device body and a camera as described in the third aspect; the camera is disposed on the device body.

[0018] Centered on the isolation layer, an inner signal electrode layer, a piezoelectric ceramic layer, and an inner ground electrode are stacked on both sides from near to far. Each inner signal electrode layer includes four inner signal electrodes, each corresponding to and electrically connected to an outer signal electrode. This forms eight piezoelectric zones corresponding to each inner signal electrode. These eight piezoelectric zones, arranged in this way, provide significant driving force with a relatively simple structure and small size, enabling a wide range of motion modes and thus achieving excellent optical image stabilization. The piezoelectric motor based on this piezoelectric actuator, with its relatively simple structure and small size, can achieve powerful macroscopic motion of the driven component, thereby meeting the miniaturization requirements of cameras and electronic devices and enabling them to possess corresponding beneficial effects. Attached Figure Description

[0019] Figure 1 and Figure 2 The piezoelectric actuator provided in the embodiment of this utility model is shown in two perspective views.

[0020] Figure 3 and Figure 4 Side views of the piezoelectric actuator provided in an embodiment of the present invention from two opposing perspectives.

[0021] Figure 5 An exploded view of the piezoelectric actuator provided in an embodiment of this utility model.

[0022] Figure 6 A schematic diagram of the planar distribution of the inner signal electrode layer of the piezoelectric actuator provided in an embodiment of this utility model.

[0023] Figure 7 A schematic diagram of the planar distribution of the piezoelectric actuator in the inner grounding electrode layer provided for an embodiment of this utility model.

[0024] Figures 8-11 This is a schematic diagram of the polarization direction of the piezoelectric partition.

[0025] Figure 12 and Figure 13 A schematic diagram of the vibration modes and driving principle of the piezoelectric actuator provided in the embodiment of this utility model.

[0026] Figure 14 This is a schematic diagram of the structure of a piezoelectric motor provided in an embodiment of the present invention.

[0027] Figure 15 and Figure 16 The diagram shows the structure of two types of cameras provided in the embodiments of this application.

[0028] Figure 17 This is a perspective view of a camera provided in an embodiment of this application.

[0029] Figure 18 This application provides an embodiment of a camera's operating route.

[0030] Figure 19 For implementation Figure 18 The driving voltage for the motion path shown.

[0031] Figure 20 This application provides an alternative operating route for a camera.

[0032] Figure 21 For implementation Figure 20 The driving voltage for the motion path shown.

[0033] Figure 22 This is the driving voltage used to achieve other optional motion paths.

[0034] Figure 23 A schematic diagram of an electronic device provided in an embodiment of this application.

[0035] The components include: piezoelectric actuator-100, drive head-110, piezoelectric body-120, protective layer-121, first protective layer-1211, second protective layer-1212, isolation layer-122, inner ground electrode-123, piezoelectric ceramic layer-124, inner signal electrode layer-125, first inner signal electrode-1251, second inner signal electrode-1252, third inner signal electrode-1253, fourth inner signal electrode-1254, first outer signal electrode-1261, second outer signal electrode-1262, third outer signal electrode-1263, fourth outer signal electrode-1264, fifth outer signal electrode-1265, sixth outer signal electrode-1266, seventh outer signal electrode-1267, eighth outer signal electrode-1268, and outer ground electrode-127. Detailed Implementation

[0036] The following description and accompanying drawings fully illustrate specific embodiments of this application to enable those skilled in the art to practice them. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operations may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of embodiments of this application includes the entire scope of the claims and all available equivalents of the claims. In this document, each embodiment may be referred to individually or collectively by the term "utility model," which is merely for convenience and, if more than one utility model is disclosed, is not intended to automatically limit the scope of the application to any single utility model or utility model concept. Relational terms such as "first" and "second" are used herein only to distinguish one entity or operation from another, without requiring or implying any actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed. The various embodiments in this document are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the structures, products, etc., disclosed in the embodiments, since they correspond to the disclosed parts, the descriptions are relatively simple; relevant details can be found in the method section.

[0037] In existing technologies, piezoelectric motor-driven cameras suffer from problems such as large size, complex structure, and insufficient driving force, making them difficult to use in miniaturized electronic devices. The inventors, through in-depth analysis of the movement principle of piezoelectric motors, discovered that the implementation of OIS (Optical Image Stabilization) function in a camera using piezoelectric motors requires two piezoelectric motors located on mutually perpendicular sides of the camera. This increases the planar dimensions and complicates the camera, increasing assembly tolerances and costs. One solution to reduce assembly tolerances and costs is to place multiple piezoelectric motors above the camera. However, in related technologies, when the piezoelectric actuator internally excites the drive head for elliptical motion, the major and minor axes are coupled, making it difficult to independently control the thrust and speed of the piezoelectric motors. Furthermore, this leads to mutual interference between the friction pairs of multiple piezoelectric motors and the driven components, ultimately making it difficult to implement unidirectional camera movement and hindering precise control of camera motion.

[0038] Based on the above analysis, the inventors, using an isolation layer as the center, stacked an inner signal electrode layer, a piezoelectric ceramic layer, and an inner ground electrode on both sides from near to far. Each inner signal electrode layer includes four inner signal electrodes, each corresponding to and electrically connected to an outer signal electrode. This forms eight piezoelectric zones corresponding to each inner signal electrode. These eight piezoelectric zones, arranged in this way, provide significant driving force with a relatively simple structure and small size, enabling a wide range of motion modes and thus achieving excellent optical image stabilization. The piezoelectric motor based on this piezoelectric actuator, with its relatively simple structure and small size, can achieve powerful macroscopic motion of the driven component, thereby meeting the miniaturization requirements of cameras and electronic devices and enabling them to possess corresponding beneficial effects.

[0039] Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 These are, respectively, perspective views, side views, and exploded views of the piezoelectric actuator provided in the embodiments of this utility model from two different perspectives. Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the piezoelectric actuator includes a drive head 110 and a piezoelectric body 120. The piezoelectric body includes an isolation layer 122, two inner grounding electrodes 123, two piezoelectric ceramic layers 124, two inner signal electrode layers 125, multiple outer signal electrodes, and an outer grounding electrode 127. An inner signal electrode layer 125, a piezoelectric ceramic layer 124, and an inner grounding electrode 123 are stacked on both sides of the isolation layer 122 from near to far. Each inner signal electrode layer 125 includes four inner signal electrodes, each corresponding to and electrically connected to an outer signal electrode. The inner grounding electrodes 123 are all electrically connected to the outer grounding electrodes 127. The drive head 110 is located on the piezoelectric body 120 in an orientation parallel to both sides of the isolation layer 122.

[0040] For ease of subsequent explanation and understanding, Figure 1The shown perspective defines an XYZ spatial rectangular coordinate system and a preset direction. The X-axis is parallel to the length direction of the piezoelectric actuator 100, the Y-axis is parallel to the width direction of the piezoelectric actuator 100, and the Z-axis is parallel to the height direction of the piezoelectric actuator 100. In this embodiment, the overall stacking direction of an inner signal electrode layer 125, a piezoelectric ceramic layer 124, and an inner ground electrode 123, stacked from near to far on both sides of the isolation layer 122, is the X-axis direction (or parallel to the X-axis direction). The following description of the XYZ coordinate system and preset direction is provided here. In this embodiment, the piezoelectric actuator 100, under high-frequency voltage excitation, causes the drive head 110 to generate micro-vibrations, which are then converted into macroscopic motion of the driven component. The micro-motion of the drive head 110 includes, but is not limited to, elliptical motion and linear motion in different directions.

[0041] The stacked isolation layer 122, inner signal electrode layer 125, piezoelectric ceramic layer 124 and inner grounding electrode 123 can be bonded and fixed together by high-temperature sintering.

[0042] In this embodiment, the drive head 110 is used to contact the driven component. Its function is to transmit and amplify the micro-motion of the stacked piezoelectric blocks and apply it to the driven component through friction to achieve macro-motion of the driven component. The drive head 110 can have a conical, cylindrical, cubic, triangular pyramid, square pyramid, hemispherical, or other shapes. The material of the drive head 110 can be metal, alloy, or ceramic. The drive head 110 is located at the center point of the top of the protective layer 121, which is also the center point of the top of the overall structure of the piezoelectric actuator 100. The drive head 110 and the piezoelectric body 120 are combined by high-temperature sintering or adhesive bonding. The stacking direction of each structural layer is along a single X-axis direction, which can be sintered in one step. The process is simple and can be mass-produced.

[0043] In this embodiment, the piezoelectric body 120 may further include a protective layer 121, which at least covers the area where the drive head 110 is located on the piezoelectric body 120, and the drive head 110 is fixed to the protective layer 121. The materials of the protective layer 121 and the insulating layer 122 may be the same as the material of the piezoelectric ceramic, or they may be other insulating rigid materials. The protective layer 121 may be combined with other related structures by high-temperature sintering or adhesive bonding. Figure 5 In the piezoelectric actuator 100 shown, a first protective layer 1211 covering two positions parallel to the isolation layer 122 and a second protective layer 1212 perpendicular to the isolation layer 122 (and opposite to each other) together constitute a protective layer 121.

[0044] The piezoelectric actuator obtained by the above structure and electrical connection relationship has an active region (a stacked combination of internal signal electrode, internal ground electrode 123 and piezoelectric ceramic layer 124) corresponding to the distribution of four internal signal electrodes in each internal signal electrode layer 125, which can be divided into 8 partitions, namely piezoelectric partition 1, piezoelectric partition 2, ..., piezoelectric partition 8, and each piezoelectric partition corresponds to an external signal electrode.

[0045] Please refer to further information. Figures 3-6 The piezoelectric partition 1 consists of a first inner signal electrode 1251, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the first inner signal electrode 1251 connected to the first outer signal electrode 1261; piezoelectric partition 2 consists of a second inner signal electrode 1252, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the second inner signal electrode 1252 connected to the second outer signal electrode 1262; piezoelectric partition 3 consists of a third inner signal electrode 1253, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the third inner signal electrode 1253 connected to the third outer signal electrode 1263; and piezoelectric partition 4 consists of a fourth inner signal electrode 1254, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the fourth inner signal electrode 1254 connected to the fourth outer signal electrode 1262. 4; Piezoelectric zone 5 is composed of the fifth inner signal electrode 1255, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the fifth inner signal electrode 1255 connected to the fifth outer signal electrode 1265; Piezoelectric zone 6 is composed of the sixth inner signal electrode 1256, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the sixth inner signal electrode 1256 connected to the sixth outer signal electrode 1266; Piezoelectric zone 7 is composed of the seventh inner signal electrode 1257, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the seventh inner signal electrode 1257 connected to the seventh outer signal electrode 1267; Piezoelectric zone 8 is composed of the eighth inner signal electrode 1258, the closest inner ground electrode 123, and the closest piezoelectric ceramic layer 124, with the eighth inner signal electrode 1258 connected to the eighth outer signal electrode 1268.

[0046] For a specific implementation method, please refer to Figure 5 Each internal signal electrode includes an internal signal plate and an internal signal tab, and the internal signal electrode is electrically connected to the corresponding external signal electrode through the internal signal tab. In another optional implementation, the internal ground electrode 123 includes an internal ground plate and an internal ground tab, and the internal ground electrode 123 is electrically connected to the external ground electrode 127 through the internal ground tab. The arrangement of the internal signal tab and / or the internal ground tab allows the electrodes to be spaced far apart in the Y-axis direction and spaced apart by piezoelectric ceramic layers 124 in the X-axis direction, thus avoiding short circuits.

[0047] Based on the distribution of the eight piezoelectric zones determined by the internal signal electrodes, eight external signal electrodes are disposed on the first and second sides of the piezoelectric body 120, four on each side. The first and second sides are opposite to each other and perpendicular to the sides of the isolation layer 122. This ultimately forms... Figure 3 and Figure 4 The distribution effect is shown. To concentrate the same type of structure, the external grounding electrode 127 can be placed on the first side or the second side. The first side and the second side can be covered by the protective layer 121, or they can be left uncovered.

[0048] The piezoelectric ceramic layer can be made of materials such as lead zirconate titanate (PZT), potassium sodium niobate (KNN), barium titanate (BT), or lithium niobate (LiNbO3). The inner signal electrode, inner ground electrode 123, outer signal electrode, and outer ground electrode 127 can be made of materials such as silver, copper, or gold.

[0049] In another optional implementation, the polarization directions of each piezoelectric section may be the same or different. For a single piezoelectric section, the direction in which the polarization electric field is applied can make the polarization direction either "inner ground electrode pointing to inner signal electrode" or "inner signal electrode pointing to inner ground electrode," thus the polarization direction of this piezoelectric section will also have two possibilities. For easier explanation and understanding later, please refer to... Figures 8 to 11 The polarization direction is indicated by white arrows. High-temperature, high-pressure polarization is applied from the external ground electrode 127 to the external signal electrodes of each piezoelectric zone. For two piezoelectric zones with overlapping projections, it can be done as follows: Figure 8 As shown, the polarization directions of both piezoelectric partitions point towards the isolation layer 122, meaning the polarization directions of the two piezoelectric partitions are opposite; alternatively, as shown... Figure 9 As shown, the polarization directions of the two piezoelectric partitions are both opposite to the isolation layer 122, meaning the polarization directions of the two piezoelectric partitions are opposite; it can also be as follows: Figure 10 As shown, the polarization directions of both piezoelectric regions are in the same direction as the X-axis; or as... Figure 11 As shown, the polarization directions of the two piezoelectric regions are opposite to the direction of the X-axis.

[0050] The specific polarization methods will not be listed here. Based on the number of piezoelectric partitions and the possible polarization directions, each piezoelectric partition has two polarization methods. Therefore, after arranging and combining the eight piezoelectric partitions as shown in the figure, there are a total of 2^8 = 256 polarization combinations.

[0051] Please refer to further details. Figure 12 and Figure 13 ,by Figure 8 The vibration modes and driving principle of the piezoelectric actuator 100 are described in detail using the polarization combination method shown as an example.

[0052] like Figure 12 By applying a high-frequency voltage between the first external signal electrode 1261, the second external signal electrode 1262, the seventh external signal electrode 1267, the eighth external signal electrode 1268 and the external ground electrode 127, the piezoelectric partitions 1, 2, 7 and 8 can be excited to vibrate at a high frequency, and the (2,1,2) vibration mode of the piezoelectric actuator 100 can be excited. Under this vibration mode, the drive head 110 of the piezoelectric actuator 100 makes elliptical motion in the XZ plane.

[0053] Alternatively, applying a high-frequency voltage between the third external signal electrode 1263, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the sixth external signal electrode 1266 and the external ground electrode 127 can excite the piezoelectric partitions 3, 4, 5 and 6 to vibrate at a high frequency, which can also excite the (2,1,2) vibration mode of the piezoelectric actuator 100. Under this vibration mode, the drive head 110 of the piezoelectric actuator 100 makes elliptical motion in the XZ plane.

[0054] like Figure 13 By applying a high-frequency voltage between the first external signal electrode 1261, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the eighth external signal electrode 1268 and the external ground electrode 127, the piezoelectric partitions 1, 4, 5 and 8 can be excited to vibrate at a high frequency, and the (1,2,2) vibration mode of the piezoelectric actuator 100 can be excited. Under this vibration mode, the drive head 110 of the piezoelectric actuator 100 makes elliptical motion in the YZ plane.

[0055] Alternatively, applying a high-frequency voltage between the second external signal electrode 1262, the third external signal electrode 1263, the sixth external signal electrode 1266, the seventh external signal electrode 1267 and the external ground electrode 127 can excite piezoelectric partitions 2, 3, 6 and 7 to vibrate at high frequency, which can also excite the (1,2,2) vibration mode of the piezoelectric actuator. Under this vibration mode, the drive head 110 of the piezoelectric actuator makes elliptical motion in the YZ plane.

[0056] The high-frequency voltage used for driving can be a sine wave, square wave, triangular wave, or other waveforms; the high-frequency voltage can be a bipolar voltage or a unipolar voltage; the frequency f of the high-frequency voltage is generally greater than 20kHz and is near the (1,2,2) and (2,1,2) vibration resonant frequencies of the piezoelectric actuator 100. In specific driving, the direction of the elliptical motion of the drive head 110 can be reversed by changing the polarity of the unipolar voltage; the direction of the elliptical motion of the drive head 110 can be reversed by changing the position where the bipolar voltage is applied. For example, changing the position of the bipolar voltage application from "between the first external signal electrode 1261, the second external signal electrode 1262, the seventh external signal electrode 1267, the eighth external signal electrode 1268 and the external ground electrode 127" to "between the third external signal electrode 1263, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the sixth external signal electrode 1266 and the external ground electrode 127" can reverse the elliptical motion direction of the drive head 110 in the XZ plane.

[0057] Please refer to Figure 14 This is a schematic diagram of the structure of the piezoelectric motor provided in an embodiment of this utility model. Figure 14 As shown, the piezoelectric motor 200 of this utility model includes a motor housing 24, a motor ball 23, a driven member 22, a bracket 21, and a piezoelectric actuator 100 provided in any of the preceding embodiments; wherein the piezoelectric actuator 100 is fixed to the bracket 21, and the bracket 21 is connected to the inner sidewall of the motor housing 24; the drive head 110 of the piezoelectric actuator 100 abuts against the driven member 22, and the motor ball 23 is disposed between the driven member 22 and the inner sidewall of the motor housing 24.

[0058] In this embodiment of the invention, the bracket 21 is used to fix the piezoelectric actuator 100 and is connected to the motor housing 24. The material of the bracket 21 can be metals such as stainless steel, iron, and copper, or plastics such as POM, PEI, and PP. The bracket 21 has a thin-layer curved structure, which can provide a certain degree of preload to the piezoelectric actuator 100, so that the piezoelectric actuator 100 and the driven component 22 can form good contact and increase the interfacial friction. The motor ball 23 is located between the driven component 22 and the motor housing 24, which is used to support the driven component 22 and reduce the friction between the driven component 22 and the motor housing 24. The piezoelectric motor 200 can convert the micro-vibration of the piezoelectric actuator 100 into macro-motion of the driven component 22.

[0059] This utility model embodiment also provides a camera, which includes an optical module, a camera housing, a camera ball bearing, and a piezoelectric actuator 100 as described in any of the preceding embodiments; the optical module is movably connected to the camera housing via the camera ball bearing; the piezoelectric actuator 100 is disposed between the camera housing and the optical module to drive the optical module 312 to move relative to the camera housing.

[0060] In a specific implementation, the camera may include multiple piezoelectric actuators, with the driving heads of the multiple piezoelectric actuators facing the same or different directions of the optical module.

[0061] Please refer to an optional implementation method. Figure 15 The camera 310 includes an optical module 312, a camera housing 311, a camera ball bearing 313, and a piezoelectric actuator 100 as described in any of the preceding embodiments. The optical module 312 is movably connected to the camera housing 311 via the camera ball bearing 313. The piezoelectric actuator 100 is disposed between the camera housing 311 and the optical module 312, specifically on the side of the optical module 312, to drive the optical module 312 to move relative to the camera housing.

[0062] for Figure 15 The camera 310 shown can achieve AF (autofocus) or OIS (optical image stabilization) functions by applying a high-frequency voltage to the piezoelectric actuator 100. For example, applying a high-frequency voltage between the first external signal electrode 1261, the second external signal electrode 1262, the seventh external signal electrode 1267, the eighth external signal electrode 1268, and the external ground electrode 127 can cause the camera 310 to move in the forward / backward or left / right direction, thereby achieving the OIS function. Applying a high-frequency voltage between the first external signal electrode 1, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the eighth external signal electrode 1268, and the external ground electrode 127 can cause the camera 310 to move up and down, thereby achieving the AF function.

[0063] For another alternative implementation method, please refer to [link / reference]. Figure 16 The camera 320 includes an optical module 322, a camera housing 321, a camera ball bearing 323, and a piezoelectric actuator 100 as described in any of the preceding embodiments. The optical module 322 is movably connected to the camera housing 321 via the camera ball bearing 323. The piezoelectric actuator 100 is disposed between the camera housing 321 and the optical module 322, specifically above the optical module 322, to drive the optical module 322 to move relative to the camera housing.

[0064] for Figure 16 The camera 320 shown can achieve OIS function by applying a high-frequency voltage to the piezoelectric driver 100. For example, applying a high-frequency voltage between the first external signal electrode 1261, the second external signal electrode 1262, the seventh external signal electrode 1267, the eighth external signal electrode 1268 and the external ground electrode 127 can make the camera 320 move left and right. Applying a high-frequency voltage between the first external signal electrode 1, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the eighth external signal electrode 1268 and the external ground electrode 127 can make the camera 320 move back and forth, thereby achieving the OIS function.

[0065] Please refer to further information. Figure 17 The camera 320 provided in this embodiment of the utility model is based on Figure 16 To further achieve this. Figure 17 In the camera 320 shown, two piezoelectric actuators (i.e., piezoelectric actuator 101 and piezoelectric actuator 102) are placed on opposite sides of the camera 320 to reduce its occupied area and balance the preload and friction of the piezoelectric actuators on the camera 320. In the camera 320, the camera housing 321, camera ball bearing 323, optical module 322, and piezoelectric actuators are arranged sequentially along the Z-axis and connected to each other.

[0066] To make the optical component 322 move along the X-axis, a high-frequency voltage can be applied between the first external signal electrode 1261, the second external signal electrode 1262, the seventh external signal electrode 1267, the eighth external signal electrode 1268, and the external ground electrode 127 of the piezoelectric actuators 101 and 102 to activate piezoelectric partitions 1, 2, 7, and 8, thereby exciting the piezoelectric actuators 101 and 102 to enter... Figure 12 The (2,1,2) vibration modes shown cause the drive head to perform elliptical motion in the XZ plane, and drive the optical component 322 to move through friction. It can be understood that activating piezoelectric partitions 3, 4, 5, and 6 can achieve the same effect.

[0067] To make the optical component 322 move along the Y-axis, a high-frequency voltage can be applied between the first external signal electrode 1261, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the eighth external signal electrode 1268, and the external ground electrode 127 of the piezoelectric actuators 101 and 102 to activate piezoelectric partitions 1, 4, 5, and 8, thereby exciting the piezoelectric actuators 101 and 102 to enter... Figure 12 The (1,2,2) vibration modes shown cause the drive head to perform elliptical motion in the YZ plane, and drive the optical component 322 to move through friction. It can be understood that activating piezoelectric partitions 2, 3, 6, and 7 can achieve the same effect.

[0068] To make the optical component 322 appear as follows Figure 18 As shown, it moves along a 45° direction in the XY plane. Figure 18A high-frequency voltage V1 can be applied between the first external signal electrode 1261, the second external signal electrode 1262, the seventh external signal electrode 1267, the eighth external signal electrode 1268, and the external ground electrode 127 of piezoelectric actuators 101 and 102, and a high-frequency voltage V2 can be applied between the first external signal electrode 1261, the fourth external signal electrode 1264, the fifth external signal electrode 1265, the eighth external signal electrode 1268, and the external ground electrode 127 of piezoelectric actuators 101 and 102. Figure 19 As shown, the high-frequency voltage V1 consists of a low potential of 0V and an AC sine wave, where the duration of the low potential portion is T1 and the duration of the AC sine wave is T2, together forming a period T; the high-frequency voltage V2 consists of a low potential of 0V and an AC sine wave, where the duration of the low potential portion is T2 and the duration of the AC sine wave is T1, together forming a period T; the AC sine wave can also be a square wave, a triangular wave, or other waveforms; the AC sine wave can also be a voltage waveform with a certain duty cycle; T1 and T2 are equal; the magnitude and duty cycle of the high-frequency voltages V1 and V2 are the same; with the above settings, the optical component 322 can move along a stepped trajectory and synthesize into a 45° direction of motion.

[0069] Of course, applying a high-frequency AC sine wave, square wave, or triangular wave waveform between the second external signal electrode 1262, the seventh external signal electrode 1267, and the external grounding electrode 127 of the piezoelectric actuator 101 and piezoelectric actuator 102 can also realize the movement of the optical component 322 in the 45° direction.

[0070] Similarly, applying a high-frequency AC sine wave, square wave, or triangular wave waveform between the fourth external signal electrode 1264, the fifth external signal electrode 1265, and the external ground electrode 127 of the piezoelectric actuator 101 and the piezoelectric actuator 102 can also achieve the movement of the optical component 322 along the 45° direction.

[0071] To make the optical component 322 appear as follows in the XY plane Figure 20 As shown, moving in any other direction can change the magnitude of the AC sine wave in high-frequency voltage V1 or high-frequency voltage V2. For example... Figure 21 As shown, increasing the AC sine wave in the high-frequency voltage V1 can increase the X component in the stepped motion trajectory of the optical component 322, thereby changing the direction of motion. To make the optical component 322 move in any other direction in the XY plane, the ratios of T1 and T2 to T in the high-frequency voltage V1 or V2 can also be changed. Figure 22 As shown, changing T1 / T from 0.5 to 0.83 and T2 / T from 0.5 to 0.17 can increase the X component in the stepped motion trajectory of the optical component 322, thereby changing the direction of motion.

[0072] Furthermore, to make the optical component 322 move in any other direction in the XY plane, the duty cycle of the AC sine wave in the high-frequency voltage V1 or V2 can be changed. For example, changing the duty cycle of the AC sine wave in the high-frequency voltage V1 from 0.4 to 0.6 can increase the X component in the stepped motion trajectory of the optical component 322, thereby changing the direction of motion.

[0073] To change the speed at which the optical component 322 moves in the XY plane, the magnitude or duty cycle of the AC sine wave in the high-frequency voltage V1 and the high-frequency voltage V2 can be increased or decreased by the same proportion at the same time.

[0074] To change the speed at which the optical component 322 moves in the XY plane, the frequencies of the AC sine waves in the high-frequency voltages V1 and V2 can be changed proportionally.

[0075] This embodiment uses a piezoelectric actuator 100 to drive the camera 3003 to move in the XY plane, offering advantages such as simple structure, power-off self-locking, fast response speed, high control precision, and low noise. Furthermore, by placing the piezoelectric actuator 100 above the camera 3003, the size of the camera 3003 in the XY plane can be significantly reduced. Combined with the motor ball bearings and the base 32, the size in the Z-axis direction can be further reduced. In addition, by changing the number of piezoelectric blocks in different regions, the magnitude of the high-frequency excitation voltage, or changing the driving frequency, the elliptical motion trajectory of the drive head 110 can be adjusted as needed, effectively adapting to scenarios requiring high-speed motion or high thrust.

[0076] This utility model embodiment also provides an electronic device, which includes a device body and a camera provided in any of the preceding embodiments; the camera is disposed on the device body.

[0077] like Figure 23 As shown, the camera 3003 is, for example, installed in the device body 41. The electronic device 400 can be a smartwatch, smartphone, tablet computer, VR device, etc. It should be noted that this application embodiment only uses a smartwatch as an example for illustration. The camera 3003 can be installed on the top of the device body 41, or on the bottom and side of the device body 41, or on a peripheral device of the electronic device 400. For the smartwatch-shaped electronic device 400, the top refers to the side of the electronic device 400 with the display screen; the bottom refers to the opposite side of the top; and the side refers to the circumferential side of the smartwatch's frame. It is understood that the definitions of terms such as front, back, and side may differ depending on the type of electronic device 400, and other types of electronic devices 400 will not be listed here.

[0078] Based on the piezoelectric actuator described above, the piezoelectric motor can achieve powerful macroscopic movement of the driven component with a relatively simple structure and small size, thereby meeting the miniaturization requirements of cameras and electronic devices and enabling cameras and electronic devices to have corresponding beneficial effects.

[0079] Note that the above are merely preferred embodiments and the technical principles applied in this utility model. Those skilled in the art will understand that this utility model is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the protection scope of this utility model. Therefore, although the embodiments of this utility model have been described in detail above, this utility model is not limited to the above embodiments. More other equivalent embodiments may be included without departing from the concept of this utility model, and the scope of this utility model is determined by the scope of the appended claims.

Claims

1. A piezoelectric actuator, characterized in that, include: Drive head (110) and piezoelectric body (120); The piezoelectric body includes an isolation layer (122), two inner grounding electrodes (123), two piezoelectric ceramic layers (124), two inner signal electrode layers (125), multiple outer signal electrodes, and an outer grounding electrode (127). The isolation layer (122) has an inner signal electrode layer (125), a piezoelectric ceramic layer (124) and an inner ground electrode (123) stacked on both sides from near to far. Each of the inner signal electrode layers (125) includes four inner signal electrodes, each of the inner signal electrodes corresponding to and electrically connected to an outer signal electrode; The inner grounding electrode (123) is electrically connected to the outer grounding electrode (127); The drive head (110) is located on the piezoelectric body (120) in an orientation parallel to both sides of the insulating layer (122).

2. The piezoelectric actuator according to claim 1, characterized in that, The piezoelectric body (120) further includes a protective layer (121), which at least covers the location of the drive head (110) on the piezoelectric body (120), and the drive head (110) is fixed to the protective layer (121).

3. The piezoelectric actuator according to claim 1, characterized in that, The external signal electrode is disposed on the first and second sides of the piezoelectric body (120), the first and second sides being opposite sides and perpendicular to the two sides of the isolation layer (122).

4. The piezoelectric actuator according to claim 3, characterized in that, The external grounding electrode (127) is disposed on the first side or the second side.

5. The piezoelectric actuator according to any one of claims 1-4, characterized in that, The stacked isolation layer (122), inner signal electrode layer (125), piezoelectric ceramic layer (124) and inner ground electrode (123) are fixedly connected by sintering.

6. The piezoelectric actuator according to any one of claims 1-4, characterized in that, The polarization directions of the piezoelectric regions corresponding to each internal signal electrode may be the same or different.

7. A piezoelectric motor, characterized in that, It includes a motor housing (24), motor balls (23), driven components (22), a bracket (21), and a piezoelectric actuator (100) as described in any one of claims 1-6; The piezoelectric actuator (100) is fixed to the bracket (21), and the bracket (21) is connected to the inner wall of the motor housing (24); The drive head (110) of the piezoelectric actuator (100) abuts against the driven member (22), and the motor ball (23) is disposed between the driven member (22) and the inner wall of the motor housing (24).

8. A camera, characterized in that, Includes an optical module, a camera housing, a camera ball bearing, and a piezoelectric actuator (100) as described in any one of claims 1-6; The optical module is movably connected to the camera housing via the camera ball bearing; The piezoelectric actuator (100) is disposed between the camera housing and the optical module to drive the optical module (312) to move relative to the camera housing.

9. The camera according to claim 8, characterized in that, The camera includes multiple piezoelectric actuators, and the drive heads (110) of the multiple piezoelectric actuators (100) are oriented in the same or different directions toward the optical module.

10. An electronic device, characterized in that, Includes the device body (41) and the camera (3003) as described in claim 8 or 9; The camera (3003) is mounted on the device body (41).

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