WO2024087956A1 - 驱动单元、压电马达、摄像模组和电子设备 - Google Patents

驱动单元、压电马达、摄像模组和电子设备 Download PDF

Info

Publication number
WO2024087956A1
WO2024087956A1 PCT/CN2023/120171 CN2023120171W WO2024087956A1 WO 2024087956 A1 WO2024087956 A1 WO 2024087956A1 CN 2023120171 W CN2023120171 W CN 2023120171W WO 2024087956 A1 WO2024087956 A1 WO 2024087956A1
Authority
WO
WIPO (PCT)
Prior art keywords
driving
material layer
piezoelectric
piezoelectric material
driving unit
Prior art date
Application number
PCT/CN2023/120171
Other languages
English (en)
French (fr)
Inventor
张百亮
秦诗鑫
郑科
刘彬
边心秀
Original Assignee
华为技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Publication of WO2024087956A1 publication Critical patent/WO2024087956A1/zh

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
    • H02N2/02—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuators; Linear positioners ; Linear motors
    • H02N2/04—Constructional details
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
    • H02N2/02—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuators; Linear positioners ; Linear motors
    • H02N2/06—Drive circuits; Control arrangements or methods
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/57—Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices

Definitions

  • the present application relates to the field of camera technology, and in particular to a driving unit, a piezoelectric motor, a camera module and an electronic device.
  • the motor of the camera module of electronic devices is mainly a voice coil motor.
  • the electromagnetic driving force of the voice coil motor is positively correlated with the magnetic field strength and the number of coil turns.
  • the photosensitive chips of camera modules are getting bigger, the lenses are getting heavier, and the auto focus (AF) stroke is getting longer.
  • the magnetic field of the voice coil motor has a limited range of action, it is difficult to meet the AF long stroke requirements of heavy-load camera modules.
  • it is necessary to enlarge the magnet and coil of the voice coil motor which increases the size and weight of the entire voice coil motor.
  • the increase in magnetic field strength will also cause magnetic interference to adjacent magnetic sensors.
  • the present application provides a driving unit, a piezoelectric motor, a camera module and an electronic device to increase the autofocus range of the camera module and improve the camera effect of the electronic device.
  • the present application provides a driving unit, which can be used as a driving component of a piezoelectric motor.
  • the driving unit may include a beam structure and a piezoelectric material layer.
  • the beam structure includes a first beam, a second beam and a third beam.
  • the first beam includes a first surface and a second surface, and the first surface and the second surface are arranged opposite to each other, and the second beam and the third beam may both be located on the first surface.
  • the second beam is arranged to intersect with the first beam
  • a first driving foot is arranged at the connection between the first beam and the second beam, and the first driving foot can extend from the connection between the first beam and the second beam in a direction away from the second beam.
  • the first driving foot can be used as the output part of the driving force of the driving unit, so that the driving unit can drive the follower by connecting the first driving foot to the follower.
  • the piezoelectric material layer can be arranged on the first surface or the second surface of the first beam, or the piezoelectric material layer can be arranged on both the first surface and the second surface.
  • the first beam and the second beam can be driven to vibrate by applying an electrical signal to the piezoelectric material layer, thereby outputting a driving force and a driving displacement at the first driving foot.
  • continuous vibration of the beam structure can be achieved, so that it continuously outputs a driving displacement in the same direction, so that the driving unit can drive the follower to continuously move in the same direction.
  • the piezoelectric motor with the driving unit is used in a camera module, the driving unit can drive the lens assembly to reciprocate, thereby effectively increasing the focusing stroke and focusing accuracy of the camera module.
  • the piezoelectric material layer can include a plurality of piezoelectric ceramic layers stacked in the direction from the first surface to the second surface, which can effectively reduce the driving voltage of the piezoelectric material layer, and can reduce the design cost of the driving circuit.
  • the piezoelectric material layer can be polarized along the stacking direction. When an electric field along the polarization direction is applied to the piezoelectric material layer, it can generate a first displacement d33 along the polarization direction; and generate a second displacement d31 in a direction perpendicular to the first displacement d33.
  • the first displacement d33 can be used to excite the vibration of the second beam and the third beam
  • the second displacement d31 can be used to excite the vibration of the first beam.
  • the vibration direction of the first beam, the second beam and the third beam can be adjusted by adjusting the electrical signal applied to the piezoelectric material layer, thereby realizing the adjustment of the driving displacement output by the beam structure, and then realizing the driving unit to drive the follower in different directions.
  • a second driving foot may be provided at the connection between the first beam and the third beam, and the second driving foot may be symmetrically arranged with the first driving foot. In this way, both the first driving foot and the second driving foot can output driving force, which can effectively increase the driving force output by the entire driving unit.
  • the second beam and the third beam can be symmetrically arranged.
  • the pre-pressure applied by the driving unit to the driven member at the first driving foot and the second driving foot can be a pair of balanced forces, thereby effectively improving the driving efficiency of the driving unit.
  • the distance between the piezoelectric material layer and the second beam can be made equal to the distance between the piezoelectric material layer and the third beam.
  • the distances between the two beams are equal, so that the piezoelectric material layer can drive the second beam and the third beam to produce symmetrical movement, so that the connection between the second beam and the first beam, and the connection between the third beam and the first beam output symmetrical driving force and driving displacement.
  • the angle between the first beam and the second beam is greater than or equal to 30° and less than or equal to 150°.
  • the angle between the first beam and the second beam can be 90°, so that the first beam and the second beam have good motion performance in their vibration direction, so that a larger driving force and driving displacement can be output at the first beam and the second beam.
  • the angle between the first beam and the third beam may also be greater than or equal to 30° and less than or equal to 150°.
  • the angle between the first beam and the third beam may be 90°, so that the first beam and the third beam have good motion performance in their vibration directions, thereby outputting a larger driving force and driving displacement at the first beam and the third beam.
  • a first notch may be provided at the connection between the first beam and the second beam, and the opening of the first notch is provided toward the area surrounded by the first beam, the second beam and the third beam.
  • a flexible hinge structure may be formed at the connection between the first beam and the second beam, which may effectively reduce the connection rigidity between the first beam and the second beam, so that the first beam and the second beam are more likely to deform.
  • a second notch may be provided at the connection between the first beam and the third beam, and the opening of the second notch is provided toward the area surrounded by the first beam, the second beam and the third beam.
  • a flexible hinge structure may be formed at the connection between the first beam and the third beam, which may effectively reduce the connection rigidity between the first beam and the third beam, so that the first beam and the third beam are more likely to deform.
  • the dimension of the beam structure in the thickness direction may be smaller than the dimension of the beam structure in the length direction and the height direction; wherein the length direction is the extension direction of the first beam, the height direction is the direction from the first surface to the second surface, and the thickness direction is the direction perpendicular to both the length direction and the height direction.
  • the beam structure may be an integrally formed structure, which can effectively improve the structural reliability of the beam structure and reduce the processing cost of the beam structure.
  • the present application further provides a piezoelectric motor, which may include a motor base, a drive unit, a carrier and a preload spring.
  • the motor base may include a housing cavity.
  • the drive unit may be arranged in the housing cavity, the drive unit includes a beam structure and a piezoelectric material layer, the beam structure includes a first beam, a second beam and a third beam, the first beam includes a first surface and a second surface arranged opposite to each other, the second beam and the third beam are located on the first surface, the second beam and the first beam are arranged to intersect, and the first beam and the third beam are arranged to intersect.
  • a first driving foot is arranged at the connection between the first beam and the second beam
  • a second driving foot is arranged at the connection between the first beam and the third beam
  • the second driving foot is arranged symmetrically with the first driving foot.
  • the piezoelectric material layer is arranged on the first surface or the second surface, or the piezoelectric material layer is arranged on both the first surface and the second surface.
  • the carrier may be arranged in the housing cavity
  • the preload spring may be fixedly connected to the carrier
  • the preload spring may include a first abutting portion and a second abutting portion, the first abutting portion may abut against the first driving foot, so that the first abutting portion undergoes elastic deformation and generates preload.
  • the second abutting portion can abut against the second driving foot, so that the second abutting portion is elastically deformed and generates a pre-pressure.
  • the carrier may include a mounting hole, and the driving unit may be used to drive the carrier to move along the axis of the mounting hole.
  • the driving unit when a first electrical signal is applied to the piezoelectric material layer, the driving unit may drive the carrier to move along a first direction; and when a second electrical signal is applied to the piezoelectric material layer, the driving unit may drive the carrier to move along a second direction, wherein the first direction and the second direction are opposite, so that the driving unit may drive the reciprocating motion of the carrier.
  • the first beam, the second beam and the third beam can be driven to vibrate by applying an electrical signal to the piezoelectric material layer, thereby outputting a driving force and a driving displacement at the first driving foot and the second driving foot.
  • continuous vibration of the beam structure can be achieved, so that it continuously outputs a driving displacement in the same direction, so that the driving unit can drive the carrier to continuously move in the same direction.
  • the driving unit can drive the lens assembly to reciprocate, thereby effectively increasing the focusing stroke and focusing accuracy of the camera module.
  • the piezoelectric material layer can include a plurality of piezoelectric ceramic layers stacked in the direction from the first surface to the second surface, which can effectively reduce the driving voltage of the piezoelectric material layer, and can reduce the design cost of the driving circuit.
  • the piezoelectric material layer can be polarized along the stacking direction. When an electric field along the polarization direction is applied to the piezoelectric material layer, it can generate a first displacement d33 along the polarization direction; and generate a second displacement d31 in a direction perpendicular to the first displacement d33.
  • the first displacement d33 can be used to excite the vibration of the second beam and the third beam
  • the second displacement d31 can be used to excite the vibration of the first beam.
  • the vibration direction of the first beam, the second beam and the third beam can be adjusted by adjusting the electrical signal applied to the piezoelectric material layer, thereby realizing the adjustment of the driving displacement output by the beam structure, and then realizing the driving unit to drive the follower in different directions.
  • the second beam and the third beam can be symmetrically arranged.
  • the pre-pressure applied by the driving unit to the driven member at the first driving foot and the second driving foot can be a pair of balanced forces, thereby effectively improving the driving efficiency of the driving unit.
  • the distance between the piezoelectric material layer and the second beam can be made equal to the distance between the piezoelectric material layer and the third beam, so that the piezoelectric material layer can drive the second beam and the third beam to produce symmetrical movement, thereby making the connection between the second beam and the first beam, and the connection between the third beam and the first beam output symmetrical driving force and driving displacement.
  • the angle between the first beam and the second beam is greater than or equal to 30° and less than or equal to 150°.
  • the angle between the first beam and the second beam can be 90°, so that the first beam and the second beam have good motion performance in their vibration direction, so that a larger driving force and driving displacement can be output at the first beam and the second beam.
  • the angle between the first beam and the third beam may also be greater than or equal to 30° and less than or equal to 150°.
  • the angle between the first beam and the third beam may be 90°, so that the first beam and the third beam have good motion performance in their vibration directions, thereby outputting a larger driving force and driving displacement at the first beam and the third beam.
  • a first notch may be provided at the connection between the first beam and the second beam, and the opening of the first notch is provided toward the area surrounded by the first beam, the second beam and the third beam.
  • a flexible hinge structure may be formed at the connection between the first beam and the second beam, which may effectively reduce the connection rigidity between the first beam and the second beam, so that the first beam and the second beam are more likely to deform.
  • a second notch may be provided at the connection between the first beam and the third beam, and the opening of the second notch is provided toward the area surrounded by the first beam, the second beam and the third beam.
  • a flexible hinge structure may be formed at the connection between the first beam and the third beam, which may effectively reduce the connection rigidity between the first beam and the third beam, so that the first beam and the third beam are more likely to deform.
  • the dimension of the beam structure in the thickness direction may be smaller than the dimension of the beam structure in the length direction and the height direction; wherein the length direction is the extension direction of the first beam, the height direction is the direction from the first surface to the second surface, and the thickness direction is the direction perpendicular to both the length direction and the height direction.
  • the beam structure may be an integrally formed structure, which can effectively improve the structural reliability of the beam structure and reduce the processing cost of the beam structure.
  • the piezoelectric motor may also include a drive unit base, the drive unit base is provided with a limit groove, and the drive unit base is fixedly connected to the motor base.
  • the beam structure may also include a clamping beam, the second beam and the third beam are symmetrically arranged relative to the clamping beam, the clamping beam is inserted into the limit groove, and the clamping beam is fixedly connected to the drive unit base.
  • the second beam and the third beam are in a free state, so that under the drive of the piezoelectric material layer, the first beam, the second beam and the third beam can bend freely and stretch and deform.
  • the clamping beam is fixedly connected to the drive unit base, it can effectively improve the stability of the drive unit vibration.
  • the motor base may include a plurality of baffles, and the plurality of baffles may be arranged to enclose and form the aforementioned accommodation cavity.
  • the plurality of baffles include a first baffle, and the drive unit base may be fixedly connected to the first baffle. In this way, the drive unit may be arranged at only one baffle of the piezoelectric motor, so that the structure of the piezoelectric motor may be more compact and the space utilization rate may be higher, thereby facilitating the miniaturization design of the piezoelectric motor.
  • At least one of the drive unit base and the motor base is provided with a first magnetic member
  • the carrier is provided with a second magnetic member
  • the first magnetic member and the second magnetic member are adsorbed to each other. Since the drive unit is only provided on one side of the piezoelectric motor, the torque of the magnetic force generated by the adsorption of the first magnetic member and the second magnetic member can be balanced with the gravity torque during the movement of the carrier and the driving torque of the drive unit, thereby effectively improving the structural stability of the piezoelectric motor.
  • the carrier may be provided with a guide mechanism, which may be located on the side of the carrier facing the first baffle.
  • the guide mechanism includes a mounting portion and a guide member, the mounting portion having a mounting groove, and a portion of the guide member is accommodated in the mounting groove.
  • the first baffle is provided with a guide groove, and a portion of the guide member is accommodated in the guide groove.
  • the guide mechanism does not need to provide additional force to balance the pre-pressure, which can effectively reduce the friction resistance during the movement of the guide member, thereby improving the driving efficiency of the drive unit.
  • the specific setting form of the guide member is not limited in the present application, and an exemplary form thereof may be a ball.
  • the guide member may also be a sliding shaft, and during the movement of the guide member, the friction between it and the guide groove is sliding friction.
  • a lubricating coating or grease may be plated on the surface of the sliding shaft to reduce the friction coefficient between the guide member and the guide groove.
  • the driving unit may be located between the two guide mechanisms, and the two guide mechanisms may be symmetrically arranged.
  • the piezoelectric motor may also be provided with a driving circuit board, and the plurality of baffles further include a second baffle.
  • the driving circuit board is arranged on the second baffle, and the second baffle can be, but is not limited to, arranged adjacent to the first baffle.
  • the driving circuit board is provided with a driving circuit, and the driving circuit is used to generate a first electrical signal and a second electrical signal.
  • the driving voltage of the piezoelectric material layer is relatively low, so the driving circuit used to drive the piezoelectric material layer is relatively simple, which can be, but is not limited to, provided by the existing IC in the piezoelectric motor, thereby avoiding the need to set a driving circuit separately for the piezoelectric material layer, thereby reducing the driving cost and making the piezoelectric motor smaller in size.
  • the piezoelectric material layer may include a first electrode and a second electrode.
  • the driving unit base may be provided with a first electrode sheet and a second electrode sheet, so that the first electrode can be electrically connected to the first output terminal of the driving circuit through the first electrode sheet, and the second electrode can be electrically connected to the second output terminal of the driving circuit through the second electrode sheet.
  • the present application also provides a camera module, which may include a lens assembly and the piezoelectric motor of the second aspect.
  • the lens assembly may be installed in the mounting hole of the carrier, and the piezoelectric motor may drive the lens assembly to reciprocate along the optical axis direction of the lens assembly, thereby realizing automatic focusing of the camera module over a large range.
  • the present application further provides an electronic device, comprising a housing and a camera module as in the second aspect, the camera module being disposed inside the housing.
  • the electronic device includes but is not limited to mobile phones, tablet computers, laptop computers, watches, cameras and other devices.
  • the camera module of the electronic device can achieve high-precision, fast response, large travel, large load and shock-resistant autofocus, so the electronic device has a better camera effect.
  • FIG1 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present application.
  • FIG2 is a schematic diagram of the structure of a camera module provided in one embodiment of the present application.
  • FIG3a is a schematic structural diagram of a driving unit provided in an embodiment of the present application.
  • FIG3b is a schematic structural diagram of a driving unit provided in another embodiment of the present application.
  • FIG3c is a schematic structural diagram of a driving unit provided in another embodiment of the present application.
  • FIG4 is a top view of a piezoelectric material layer provided in one embodiment of the present application.
  • Fig. 5 is a cross-sectional view of the piezoelectric material layer shown in Fig. 4 at an A-A level;
  • FIG6a is a schematic diagram of the structure of a driving circuit provided in an embodiment of the present application.
  • FIG6b is a driving signal generated by the driving circuit in FIG6a;
  • FIG7a is a vibration mode of a driving unit in a first working mode provided by an embodiment of the present application.
  • FIG7b is a diagram showing the vibration mode of the driving unit in the second working mode provided by an embodiment of the present application.
  • FIG8 is an exploded view of a piezoelectric motor provided in one embodiment of the present application.
  • FIG9 is a schematic diagram of the assembly structure of the piezoelectric motor shown in FIG8;
  • FIG10 is a schematic diagram of the connection relationship between a drive unit base, a drive unit, and a pre-stressed spring sheet provided in an embodiment of the present application;
  • FIG11 is a schematic structural diagram of the structure shown in FIG10 at another angle
  • FIG12 is a schematic diagram of a partial structure of a piezoelectric motor provided in one embodiment of the present application.
  • FIG13 is a schematic diagram of a partial structure of a piezoelectric motor provided in another embodiment of the present application.
  • FIG. 14 is an exploded view of a camera module provided in one embodiment of the present application.
  • references to "one embodiment” or “some embodiments” etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application.
  • the phrases “in one embodiment”, “in some embodiments”, “in some other embodiments”, “in some other embodiments”, etc. appearing in different places in this specification do not necessarily all refer to the same embodiment, but mean “one or more but not all embodiments", unless otherwise specifically emphasized in other ways.
  • the terms “including”, “comprising”, “having” and their variations all mean “including but not limited to”, unless otherwise specifically emphasized in other ways.
  • Piezoelectric motor also known as ultrasonic motor
  • electronic devices include but are not limited to mobile phones, tablet computers, laptops, phone watches, mobile camera devices, etc.
  • Figure 1 is a structural schematic diagram of an electronic device provided by the present application.
  • the electronic device may include a housing 1 and a processor 2, a display module (not shown in the figure) and a camera module 3 disposed inside the housing 1.
  • the electronic device may also include components such as speakers, microphones, antennas, and microphones not shown in the figure.
  • the housing 1 is also divided into a front cover and a rear cover.
  • the front cover and the rear cover of the housing 1 can be provided with a camera module 3.
  • a camera hole is provided on the rear cover.
  • the camera module 3 is arranged inside the housing 1, and light is collected through the camera hole of the rear cover to shoot an image.
  • the camera module 3 and the display module are both electrically connected to the processor 2.
  • the processor 2 controls the camera module 3 to shoot.
  • the camera module 3 transmits the collected image information to the processor 2 and displays the image in the display module.
  • the camera module 3 may include a lens assembly 301 and a piezoelectric motor 302, as shown in FIG2 , which is a schematic diagram of the structure of a camera module 3 provided by the present application.
  • the lens assembly 301 is mounted on the light incident side of the piezoelectric motor 302, and the piezoelectric motor 302 can drive the lens assembly 301 to reciprocate along its optical axis, and its movement direction can be represented by the bidirectional arrow in FIG2 , thereby realizing the automatic focus of the camera module 3.
  • users have also put forward higher requirements for the automatic focus of the camera module 3, such as requiring the camera module 3 to have a larger automatic focus stroke.
  • the driving unit is an important driving element in the piezoelectric motor, and its driving efficiency for the lens assembly 301 has a direct impact on the autofocus stroke of the camera module 3 using the piezoelectric motor 302.
  • the existing piezoelectric motor usually sets a matching driving circuit for the driving unit separately, which leads to high driving cost and increases the size of the camera module.
  • the driving unit provided in the present application is intended to solve the above-mentioned problems, so that the driving unit can be driven by the existing driving circuit in the electronic device through the design of the structure and working mode of the driving unit, so as to reduce the driving cost while avoiding the increase of the volume of the camera module.
  • the number of driving feet of the driving unit can be designed so that the pre-pressure applied by the driving unit to the lens assembly can be self-balanced, which is conducive to improving the driving efficiency of the driving unit, thereby effectively increasing the autofocus stroke of the camera module, so that the camera effect of the electronic device using the camera module can be improved.
  • Fig. 3a is a schematic diagram of the structure of a driving unit 3021 provided in an embodiment of the present application.
  • the driving unit may include a beam structure 30211 and a piezoelectric material layer 30212.
  • the beam structure 30211 may include a first beam 302111, a second beam 302112 and a third beam 302113, and the second beam 302112 and the third beam 302113 may be located on the same side of the first beam 302111, for example, the second beam 302112 and the third beam 302113 may be both arranged on the first surface 3021111 of the first beam 302111.
  • the first beam 302111 has a first end 3021113 and a second end 3021114.
  • the second beam 302112 can be connected to the first end 3021113 of the first beam 302111, and the third beam 302113 can be connected to the second end 3021114 of the first beam 302111.
  • the material of the beam structure 30211 is not specifically limited.
  • the material of the beam structure 30211 can be a metal material that is easy to deform, such as stainless steel or phosphor bronze.
  • the beam structure 30211 can be an integrally formed structure, which is conducive to improving the structural reliability of the beam structure 30211 and reducing the processing cost of the beam structure 30211.
  • the materials of the first beam 302111, the second beam 302112 and the third beam 302113 may be the same.
  • the first beam 302111, the second beam 302112 and the third beam 302113 may also be independent structures formed separately and then connected by welding or the like.
  • the materials of the first beam 302111, the second beam 302112 and the third beam 302113 may be the same or different.
  • the piezoelectric material layer 30212 may be used to drive the first beam 302111, the second beam 302112 and the third beam 302113 of the beam structure 30211 to deform to generate vibration, so that the beam structure 30211 can output a driving force and drive displacement.
  • the driving unit 3021 shown in FIG. 3a is still taken as an example, wherein the first beam 302111 and the second beam 302112 can be arranged to intersect.
  • the intersection of two beams means that there is an angle ⁇ that is not 0 at the connection between the two, and the angle ⁇ can be, but is not limited to, greater than or equal to 30° and less than or equal to 150°.
  • the angle between the first beam 302111 and the second beam 302112 at their connection can be 90°, and at this time, the first beam 302111 and the second beam 302112 can be considered to be in an orthogonal relationship.
  • the first beam 302111 and the second beam 302112 can have good motion performance in their extension direction, respectively, so that they have a larger driving displacement in the motion direction, so that the step in each driving cycle is larger, and has a higher motion speed.
  • the response time of the driving unit 3021 can be effectively shortened, so that when the piezoelectric motor 302 with the driving unit 3021 is used in the camera module 3, the focus adjustment efficiency can be effectively improved.
  • a first notch 302114 may be provided at the connection between the first beam 302111 and the second beam 302112, and the opening of the first notch 302114 may be provided toward the area surrounded by the first beam 302111, the second beam 302112, and the third beam 302113.
  • a flexible hinge structure may be formed at the connection, thereby effectively reducing the connection strength at the connection between the two. In this way, the vibration displacement of the first beam 302111 and the second beam 302112 at the connection may be increased, and the vibration speed and output driving force thereof may be increased.
  • the first beam 302111 and the third beam 302113 may also be arranged to intersect.
  • the angle between the first beam 302111 and the third beam 302113 may also be, but not limited to, greater than or equal to 30° and less than or equal to 150°.
  • the angle between the first beam 302111 and the second beam 302112 at their connection may be 90°, so that the first beam 302111 and the third beam 302113 are in an orthogonal relationship.
  • the first beam 302111 and the third beam 302113 may have good motion performance in their extension directions, so that they have a larger driving displacement in the motion direction, a larger step in each driving cycle, and a higher motion speed.
  • a second notch 302115 may be provided at the connection between the first beam 302111 and the third beam 302113, and the opening of the second notch 302115 may be provided toward the area surrounded by the first beam 302111, the second beam 302112 and the third beam 302113.
  • a flexible hinge structure may be formed at the connection, thereby effectively reducing the connection strength at the connection between the two. In this way, the vibration displacement of the first beam 302111 and the third beam 302113 at the connection may be increased, and the vibration speed and output driving force thereof may be increased.
  • the second beam 302112 and the third beam 302113 can be symmetrically arranged, which is beneficial to improving the stability of the movement of the beam structure 30211.
  • the driving force output by the driving unit 3021 is more stable, so as to effectively improve the movement stability of the lens assembly 301 when the lens assembly 301 shown in FIG. 2 is driven to move by the driving unit 3021.
  • a driving force and a driving displacement can be formed at the connection between the first beam 302111 and the second beam 302112.
  • a first driving foot 302116 can be provided at the connection between the second beam 302112 and the first beam 302111, and the first driving foot 302116 can be located outside the area surrounded by the first beam 302111, the second beam 302112 and the third beam 302113.
  • the first driving foot 302116 can extend from the connection between the first beam 302111 and the second beam 302112 in a direction away from the second beam 302112.
  • a second driving foot 302117 may be provided at the connection between the third beam 302113 and the first beam 302111, and the second driving foot 302117 may be located outside the area surrounded by the first beam 302111, the second beam 302112 and the third beam 302113.
  • the second driving foot 302117 may extend from the connection between the first beam 302111 and the third beam 302113 in a direction away from the third beam 302113.
  • the first driving foot 302116 and the second driving foot 302117 can be symmetrically arranged, so that the driving force and driving displacement generated at the first driving foot 302116 and the second driving foot 302117 can be symmetrical during the vibration of the beam structure 302111.
  • the first beam 302111 can also include a second surface 3021112, and the first surface 3021111 and the second surface 3021112 are arranged opposite to each other.
  • the component of the driving force generated at the first driving foot 302116 can be equal in magnitude and in the same direction as the component of the driving force generated at the second driving foot 302117, so that the beam structure 30211 can output a stable driving force and driving displacement in this direction, and the driving unit 3021 can also have a larger driving force and driving displacement in this direction.
  • the dimension of the beam structure 30211 in the thickness h direction can be made smaller than the dimension of the beam structure 30211 in the length direction and the height direction.
  • the length direction of the beam structure 30211 is the extension direction of the first beam 302111.
  • the height direction of the beam structure 30211 can be understood as the direction from the first surface 3021111 to the second surface 3021112.
  • the second beam 302112 and the third beam 302113 are arranged orthogonally to the first beam 302111, the height direction of the beam structure 30211 is also the extension direction of the second beam 302112 and the third beam 302113 extending from the first beam 302111.
  • the thickness direction of the beam structure 30211 is perpendicular to both its length direction and height direction.
  • the first beam 302111, the second beam 302112 and the third beam 302113 can be made the same in the thickness direction.
  • the vibration of the beam structure 30211 can be achieved more easily, so that the drive unit 3021 has lower setting requirements for the drive signal of the piezoelectric material layer 30212, which is beneficial to reduce the driving cost.
  • the piezoelectric material layer 30212 can be arranged on the first beam 302111, and it can be fixed to the first beam 302111 by, but not limited to, bonding or welding.
  • the present application does not specifically limit the arrangement of the piezoelectric material layer 30212 on the first beam 302111.
  • the piezoelectric material layer 30212 can be arranged on the second surface 3021112 of the first beam 302111.
  • FIG3b is a schematic diagram of the structure of the driving unit 3021 provided in another embodiment of the present application, in which the piezoelectric material layer 30212 can be arranged on the first surface 3021111.
  • the piezoelectric material layer 30212 may be provided on only one surface of the first beam 302111, or may be provided on both surfaces of the first beam 302111.
  • the piezoelectric material layer 30212 is provided on both the first surface 3021111 and the second surface 3021112 of the first beam 302111.
  • only one piezoelectric material layer 30212 may be provided on one surface of the first beam 302111, or two or more piezoelectric material layers 30212 may be provided.
  • the distance between the piezoelectric material layer 30212 and the second beam 302112 is equal to the distance between the piezoelectric material layer 30212 and the third beam 302113.
  • the one piezoelectric material layer 30212 when there is one piezoelectric material layer 30212, the one piezoelectric material layer 30212 can be disposed at the middle position between the second beam 302112 and the third beam 302113, and when there are two or more piezoelectric material layers 30212, the two or more piezoelectric material layers 30212 can be disposed between the second beam 302112 and the third beam 302113, and the two or more piezoelectric material layers 30212 can be symmetrically disposed.
  • the setting position of the piezoelectric material layer 30212 on the beam structure 30211 has an important influence on the vibration of the beam structure 30211.
  • the structural setting of the piezoelectric material layer 30212 itself and the selection of the driving signal of the piezoelectric material layer 30212 will also affect the vibration of the beam structure 30211.
  • FIG. 4 is a top view of the piezoelectric material layer 30212 provided in one embodiment of the present application.
  • the piezoelectric material layer 30212 may include a plurality of stacked piezoelectric ceramic layers, wherein the material of the piezoelectric ceramic layer may be lead ceramic or lead-free ceramic, the lead ceramic may be, for example, lead zirconate titanate piezoelectric ceramic, and the lead-free ceramic may be, for example, barium titanate piezoelectric ceramic.
  • the piezoelectric material layer 30212 include multiple piezoelectric ceramic layers, it is helpful to reduce the driving voltage of the piezoelectric material layer 30212.
  • the driving voltage of the piezoelectric material layer 30212 can be adjusted, and the driving voltage can be 2.8V to 3.5V. Since the thickness of each layer of piezoelectric ceramics can affect the driving voltage of the piezoelectric material layer 30212, in the present application, the thickness of each layer of piezoelectric ceramics can be set to 5 ⁇ m to 50 ⁇ m, and can be 15 ⁇ m, 20 ⁇ m, 31 ⁇ m, 40 ⁇ m or 45 ⁇ m, etc., so that the driving voltage of the piezoelectric material layer 30212 is lower.
  • the driving voltage is relatively low, it can be provided by an existing integrated circuit (IC) in the electronic device. There is no need to set up a separate driving circuit for the piezoelectric material layer 30212, which can effectively reduce the driving cost and avoid the increase in the volume of the piezoelectric motor 302 using the driving unit, thereby facilitating the miniaturization design of the piezoelectric motor 302.
  • IC integrated circuit
  • Fig. 5 is an A-A cross-sectional view of the piezoelectric material layer 30212 shown in Fig. 4.
  • the piezoelectric material layer 30212 includes a first electrode 302121 and a second electrode 302122, wherein the first electrode 302121 includes a first external electrode 3021211 and a first internal electrode 3021212, and the second electrode 302122 includes a second external electrode 3021221 and a second internal electrode 3021222.
  • the first external electrode 3021211 and the second external electrode 3021221 are disposed on the surface of the piezoelectric material layer 30212, and the first internal electrode 3021212 and the second internal electrode 3021222 are disposed inside the piezoelectric material layer 30212.
  • the first external electrode 3021211 and the first internal electrode 3021212 are electrically connected, and the second external electrode 3021221 and the second internal electrode 3021222 are electrically connected.
  • the first internal electrode 3021212 and the second internal electrode 3021222 are alternately arranged.
  • the piezoelectric material layer 30212 can be polarized along its stacking direction, so that when an electric field along the polarization direction is applied to the piezoelectric material layer 30212, it can generate a first displacement d33 along the polarization direction; and generate a second displacement d31 in a direction perpendicular to the first displacement d33.
  • the first displacement d33 can be used to excite the second beam 302112 and the third beam 302113 to vibrate
  • the second displacement d31 can be used to excite the first beam 302111 to vibrate.
  • the first displacement d33 and the second displacement d31 can be generated by applying an alternating current signal of a certain frequency to the first electrode 302121 and the second electrode 302122 of the piezoelectric material layer 30212.
  • the alternating current signal can be, but is not limited to, a sine wave, a PWM wave, or a three-dimensional wave. Angular wave, etc.
  • the driving circuit of its IC can directly generate a PWM wave
  • the PWM wave generated by the IC can be used to drive the piezoelectric material layer 30212.
  • FIG. 6a is a schematic diagram of the structure of a driving circuit provided in an embodiment of the present application.
  • the driving circuit can be an H-bridge provided by an IC, and the H-bridge includes a first output terminal 401 and a second output terminal 402.
  • the first output terminal 401 can be electrically connected to the first electrode 302121 of the piezoelectric material layer 30212 shown in FIG. 4 or FIG. 5
  • the second output terminal 402 can be electrically connected to the second electrode 302122 of the piezoelectric material layer 30212 shown in FIG. 4 or FIG. 5.
  • FIG. 6b shows two driving signals generated by the H-bridge.
  • the signal frequency of the driving signal generated by the H-bridge may be denoted as f0.
  • the driving unit 3021 can generate a driving displacement and a driving force during the vibration process, and the driving displacement and the driving force can be used to drive the lens assembly 301 to reciprocate along the optical axis.
  • the driving unit 3021 can have two working modes, namely the first working mode and the second working mode. Among them, in the first working mode and the second working mode, the driving unit 3021 can generate a driving displacement in opposite directions. Exemplarily, in the first working mode, the driving unit 3021 can drive the lens assembly 301 to move in a direction close to the object image, and in the second working mode, the driving unit 3021 can drive the lens assembly 301 to move in a direction away from the object image.
  • the signal frequency of the driving signal in order to make the driving unit 3021 vibrate, can be made close to the natural frequency of the driving unit 3021 in the corresponding working mode according to the resonance principle, so as to resonate the piezoelectric material layer 30212 and the beam structure 30211.
  • the natural frequency of the driving unit 3021 in the first working mode can be recorded as f1
  • the natural frequency of the driving unit 3021 in the second working mode can be recorded as f2.
  • FIG. 7a shows the vibration mode of the driving unit 3021 in the first working mode.
  • the first beam 302111, the second beam 302112 and the third beam 302113 of the driving unit 3021 are bent and stretched, and strong vibrations can be generated at the first driving foot 302116 and the second driving foot 302117.
  • the first driving foot 302116 can generate a vibration displacement of the first three quadrants, and at this time, the movement direction of the first driving foot 302116 can be represented by the solid line with double arrows in FIG. 7a; the second driving foot 302117 can generate a vibration displacement of the second four quadrants, and at this time, the movement direction of the second driving foot 302117 can be represented by the dotted line with double arrows in FIG. 7a.
  • FIG. 7b shows the vibration mode of the driving unit 3021 in the second working mode.
  • the first beam 302111, the second beam 302112 and the third beam 302113 of the driving unit 3021 are bent and stretched, and strong vibrations can be generated at the first driving foot 302116 and the second driving foot 302117.
  • the first driving foot 302116 can generate a vibration displacement of the second and fourth quadrants, and at this time, the movement direction of the first driving foot 302116 can be represented by the solid line with double arrows in FIG. 7a; the second driving foot 302117 can generate a vibration displacement of the third quadrant, and at this time, the movement direction of the second driving foot 302117 can be represented by the dotted line with double arrows in FIG. 7a.
  • the driving signal generated by the H-bridge can be recorded as a first electrical signal and a second electrical signal, respectively, wherein the signal frequency f0 of the first electrical signal is close to the natural frequency f1, and the signal frequency f0 of the second electrical signal is close to the natural frequency f2.
  • the driving unit 3021 can be made to vibrate in opposite directions by switching the signal frequency of the driving signal output by the driving circuit, so that the driving unit 3021 outputs driving displacement and driving force in opposite directions.
  • the structure of the driving circuit is relatively simple, which is beneficial to reduce the driving cost.
  • the driving unit 3021 can be driven by the driving signal to always vibrate in one direction, thereby continuously outputting a driving force and a driving displacement in the direction.
  • the driving unit 3021 can drive the lens assembly 301 to continuously move in one direction, which is conducive to meeting the large-stroke focusing requirement of the lens assembly 301.
  • the piezoelectric motor 302 may include a driving unit base 3022, which may provide support and limit the driving unit 3021.
  • the driving unit base 3022 may be provided with a limiting groove 30221, and the beam structure 30211 may also include a clamping beam 302118, and the second beam 302112 and the third beam 302113 may be symmetrically arranged relative to the clamping beam 302118.
  • the clamping beam 302118 may be inserted into the limiting groove 30221, and the clamping beam 302118 is fixedly connected to the driving unit base 3022, and the connection method may be, but is not limited to, welding or bonding. At this time, the second beam 302112 and the third beam 302113 of the driving unit 3021 are in a free state. Thus, under the drive of the piezoelectric material layer 30212, the first beam 302111, the second beam 302112 and the third beam 302113 of the beam structure 30211 can bend and stretch freely. And because the clamping beam 302118 is fixedly connected to the driving unit base 3022, it can effectively improve the vibration of the driving unit 3021. stability.
  • the piezoelectric motor 302 may further include a motor base 3023.
  • the shape of the motor base 3023 is not specifically limited, and it may be exemplarily a rectangular frame structure as shown in FIG8.
  • the motor base 3023 may include a receiving cavity 30231, and the drive unit 3021 may be received in the receiving cavity 30231.
  • the drive unit base 3022 may be fixedly connected to the motor base 3023.
  • the motor base 3023 may further include a plurality of baffles, which may be arranged to surround the receiving cavity 30231.
  • the plurality of baffles may include a first baffle 30232, so that the first baffle 30232 may be provided with an avoidance opening 302321, so that the drive unit base 3022 may be arranged in the avoidance opening 302321, and the drive unit base 3022 may be fixedly connected to the first baffle 30232, and the connection method may be but is not limited to welding or bonding.
  • the driving unit 3021 can be only set at a baffle of the motor base 3023, which can make the structure of the piezoelectric motor 302 more compact and the space utilization rate higher, thereby facilitating the miniaturization design of the piezoelectric motor 302.
  • the portions of the first baffle 30232 located on both sides of the avoidance opening 302321 can be thinned to form a first thinned area 302322 and a second thinned area 302323 on the first baffle 30232.
  • the drive unit base 3022 can include a first overlap portion 30222 and a second overlap portion 30223.
  • FIG9 is a schematic diagram of the assembly structure of the piezoelectric motor 302 shown in FIG8.
  • the first overlap portion 30222 can overlap the first thinning area 302322
  • the second overlap portion 30223 can overlap the second thinning area 302323, and the first overlap portion 30222 and the first thinning area 302322 are fixedly connected, and the second overlap portion 30223 and the second thinning area 302323 are fixedly connected.
  • the surface of the remaining part of the first baffle 30232, except the first thinning area 302322 and the second thinning area 302323, which is away from the accommodating cavity 30231, can be flush with the surface of the first overlap portion 30222 and the second overlap portion 30223 which is away from the accommodating cavity 30231, so that the drive unit base 3022 has a relatively flat outer surface.
  • the driving unit base 3022 may be provided with a first electrode sheet 30224 and a second electrode sheet 30225.
  • the specific arrangement of the first electrode sheet 30224 and the second electrode sheet 30225 is not limited, and the exemplary arrangement may be a metal spring sheet with conductive properties, or a flexible printed circuit (FPC), etc.
  • the first electrode sheet 30224 may be in conductive contact with the first electrode 302121, and the second electrode sheet 30225 may be in conductive contact with the second electrode 302122.
  • the first electrode sheet 30224 may be electrically connected to the first output terminal 401 of the driving circuit as shown in FIG.
  • the second electrode sheet 30225 may be electrically connected to the second output terminal 402 of the driving circuit, thereby realizing the electrical connection between the piezoelectric material layer 30212 and the driving circuit.
  • the first electrode sheet 30224 and the first output terminal 401 of the driving circuit, as well as the second electrode sheet 30225 and the second output terminal 402 of the driving circuit, may be directly connected or indirectly connected, which is not specifically limited in the present application.
  • the motor base 3023 may be provided with a first circuit connection port 30233 and a second circuit connection port 30234, the first circuit connection port 30233 may be electrically connected to the first output terminal 401, and the second circuit connection port 30234 may be electrically connected to the second output terminal 402.
  • the first circuit connection port 30233 is provided corresponding to the first electrode sheet 30224
  • the second circuit connection port 30234 is provided corresponding to the second electrode sheet 30225.
  • the first electrode sheet 30224 can be conductively contacted with the first circuit connection port 30233, and the second electrode sheet 30225 can be conductively contacted with the second circuit connection port 30234, thereby realizing electrical connection between the piezoelectric material layer 30212 and the driving circuit.
  • the piezoelectric motor 302 may also be provided with a driving circuit board 30235, which may be, but not limited to, a printed circuit board (PCB) or an FPC.
  • the driving circuit board 30235 may be provided on a baffle of the motor base 3023.
  • the driving circuit board 30235 may be provided on a second baffle 30236 of the motor base 3023, wherein the second baffle 30236 and the first baffle 30232 may be provided adjacent to each other.
  • an IC may be provided on the driving circuit board 30235, which may be used to provide a driving circuit for the piezoelectric material layer 30212, that is, the driving circuit may generate a first electrical signal and a second electrical signal.
  • the piezoelectric motor 302 may further include a carrier 30237 and a pre-compression spring 30238, the carrier 30237 and the pre-compression spring 30238 may be accommodated in the accommodating chamber 30231, and the carrier 30237 and the pre-compression spring 30238 are fixedly connected.
  • the carrier 30237 has a mounting hole 302373, and the carrier 30237 may reciprocate along the axial direction of the mounting hole 302373 in the accommodating chamber 30231.
  • the carrier 30237 may serve as a bearing component of the lens assembly 301 as shown in FIG.
  • the lens assembly 301 may be mounted in the mounting hole 302373, and the carrier 30237 may drive the lens assembly 301 to reciprocate along the axial direction of the mounting hole 302373 during the movement, thereby realizing the reciprocating movement of the lens assembly 301 along its optical axis direction.
  • the pre-load spring 30238 has a first abutting portion 302381 and a second abutting portion 302382, wherein the first driving foot 302116 can abut against the first abutting portion 302381 to cause the first abutting portion 302381 to elastically deform and generate pre-pressure; the second driving foot 302117 can abut against the second abutting portion 302382 to cause the first abutting portion 302381 to elastically deform and generate pre-pressure.
  • the driving unit 3021 vibrates, During the process, the driving force generated can act on the pre-stressed spring sheet 30238, thereby driving the carrier 30237 to reciprocate along the axial direction of the mounting hole 302373.
  • the driving unit 3021 can drive the carrier 30237 to move along a first direction; and when a second electrical signal is applied to the piezoelectric material layer 30212, the driving unit 3021 can drive the carrier 30237 to move along a second direction, wherein the first direction and the second direction are two opposite directions along the axial direction of the mounting hole 302373.
  • the driving force and driving displacement generated at the first driving foot 302116 and the second driving foot 302117 can be symmetrical. Based on this, the pre-pressure generated by the abutment between the first driving foot 302116 and the first abutment portion 302381 and the pre-pressure generated by the abutment between the second driving foot 302117 and the second abutment portion 302382 can form a pair of balanced forces.
  • FIG11 is a schematic diagram of the structure shown in FIG10 at another angle.
  • FIG11 shows the structural arrangement of the drive unit base 3022 facing the side of the accommodating cavity 30231 shown in FIG8 .
  • the drive unit base 3022 may also be provided with a first magnetic member 30226 , which may be one, and the one magnetic member may be arranged in the middle of the drive unit base 3022 .
  • first magnetic member 30226 may also be two or more, for example, in the embodiment shown in FIG11 , there are two first magnetic members 30226 , and the two first magnetic members 30226 are arranged on both sides of the limiting groove 30221 , and the two first magnetic members 30226 may be arranged symmetrically relative to the limiting groove 30221 .
  • Fig. 12 is a schematic diagram of a partial structure of the piezoelectric motor 302.
  • the carrier 30237 may also be provided with a second magnetic member 302371, which may be provided on the side of the carrier 30237 facing the driving unit 3021 as shown in Fig. 9.
  • the second magnetic member 302371 and the first magnetic member 30226 may be mutually adsorbed, wherein the number of the first magnetic member 30226 and the second magnetic member 302371 may be the same, for example, both may be two, so that the first magnetic member 30226 and the second magnetic member 302371 may be adsorbed one by one.
  • the driving unit 3021 is only arranged on one side of the piezoelectric motor 302, the torque of the magnetic force generated by the adsorption of the first magnetic member 30226 and the second magnetic member 302371 can be balanced with the gravitational torque of the carrier 30237 during movement and the driving torque of the driving unit 3021, thereby effectively improving the structural stability of the piezoelectric motor 302.
  • first magnetic member 30226 can be provided on the motor base 3023 in addition to the drive unit base 3022. It can also be understood that the first magnetic member 30226 can be provided on at least one of the drive unit base 3022 and the motor base 3023, as long as the first magnetic member 30226 and the second magnetic member 302371 can balance the driving force of the drive unit 3021 and the gravity of the carrier 30237 in various motion states through the magnetic attraction.
  • first magnetic member 30226 and the second magnetic member 302371 can be magnetic structural members, such as magnets, etc.; or they can be structural members that can be attracted by magnetic structural members but do not have magnetism themselves, such as structural members made of iron.
  • the carrier 30237 may further be provided with a guide mechanism 302372, which may be located on the side of the carrier 30237 facing the first baffle 30232.
  • the guide mechanism 302372 may include a mounting portion 3023721 and a guide member 3023722, wherein the mounting portion 3023721 has a mounting groove 30237211, and a portion of the guide member 3023722 is accommodated in the mounting groove 30237211.
  • a guide groove 302324 is provided on the side of the first baffle 30232 facing the accommodating cavity 30231, and a portion of the guide member 3023722 may be accommodated in the guide groove 302324.
  • the guide member 3023722 can move in the guide groove 302324, thereby providing a guide for the movement of the carrier 30237, which is beneficial to improving the stability of the movement of the carrier 30237.
  • the adsorption force between the first magnetic member 30226 and the second magnetic member 302371 can also enable the carrier 30237 to press the guide member 3023722 toward the guide groove 302324, so that the magnetic force between the first magnetic member 30226 and the second magnetic member 302371 can be balanced with the gravitational moment generated by the self-weight of the carrier 30237 relative to the contact point between the carrier 30237 and the guide member 3023722, which is beneficial to improve the stability of the carrier 30237 moving along the first direction and the second direction.
  • the driving unit 3021 can be located between the two guide mechanisms 302372, and the two guide mechanisms 302372 can be symmetrically arranged.
  • the present application does not limit the specific arrangement form of the guide member 3023722.
  • the guide member 3023722 can be a ball.
  • the number of balls can be selected according to the extension length of the guide groove 302324. For example, in the embodiment shown in FIG12, three balls are arranged in one guide groove 302324.
  • the guide member 3023722 can also be a sliding shaft.
  • the friction force between the guide member 3023722 and the guide groove 302324 is a sliding friction force.
  • a lubricating coating or grease can be applied on the surface of the sliding shaft to reduce the friction coefficient between the guide member 3023722 and the guide groove 302324.
  • the pre-pressure generated by the abutment between the first driving foot 302116 and the first abutment portion 302381 is
  • the preload generated by the contact between the foot 302117 and the second contact portion 302382 is a pair of balancing forces. Therefore, the guide mechanism 302372 does not need to provide additional force to balance the preload, which can effectively reduce the friction resistance during the movement of the guide member 3023722, thereby improving the driving efficiency of the driving unit 3021.
  • the piezoelectric motor 302 provided in the above embodiment of the present application can be used in various camera modules 3.
  • FIG14 is an exploded view of a camera module 3 provided in an embodiment of the present application.
  • the camera module 3 shown in FIG14 can be used as a front camera of an electronic device or as a rear camera of an electronic device, which is not strictly limited here.
  • the camera module 3 may include a lens assembly 301 and a piezoelectric motor 302, wherein the lens assembly 301 may be installed on the light incident side of the piezoelectric motor 302, and specifically, the lens assembly 301 may be installed on a carrier 30237.
  • the piezoelectric motor 302 can drive the lens assembly 301 to reciprocate along the optical axis direction of the lens assembly 301 to achieve automatic focusing of the camera module 3.
  • the camera module 3 may further include a housing 303, which may be buckled on the piezoelectric motor 302, and the housing 303 may be connected to the outer edge of the motor base 3023.
  • the housing 303 may be detachably connected to the motor base 3023, and the connection method may be, but is not limited to, a snap connection.
  • the housing 303 also has a lens hole 3031, and at least a portion of the lens assembly 301 may extend from the lens hole 3031 to the outside of the housing 303.
  • the camera module 3 may also include an image sensor (not shown in FIG. 14 ), etc.
  • the image sensor may be fixed to and electrically connected to a circuit board, and the circuit board may be, but is not limited to, the driving circuit board 30235 shown in FIG. 8 .
  • the image sensor is used to receive the optical signal gathered from the lens assembly 301 and convert the optical signal into an electrical signal, and the formed electrical signal may be transmitted to the processor 2 of the electronic device through the circuit board.
  • the camera module 3 provided in the present application has a piezoelectric motor 302 that can achieve high-precision, fast response, large stroke (>5mm), large load (g-level), anti-vibration or even vibration-free autofocus. Therefore, an electronic device using the camera module 3 can have a better camera effect, which is beneficial to improving the product competitiveness of the electronic device.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)

Abstract

本申请提供了一种驱动单元、压电马达、摄像模组和电子设备。该驱动单元包括梁结构和压电材料层。其中，梁结构包括第一梁、第二梁和第三梁，第一梁包括相背设置的第一面和第二面，第二梁和第三梁位于第一面，第二梁与第一梁相交设置；第一梁和第二梁的连接处有第一驱动足，且自第一梁和第二梁的连接处，第一驱动足向背离第二梁的方向延伸；压电材料层设置于第一梁的第一面和/或第二面。应用有该驱动单元的压电马达在用于摄像模组时，通过对施加于压电材料层的电信号的频率进行调整，可使驱动单元驱动镜头组件沿光轴方向往返运动，其可有效的提高摄像模组的自动对焦行程、对焦精度和对焦速度。从而有利于提升电子设备的摄像效果。

Description

驱动单元、压电马达、摄像模组和电子设备
相关申请的交叉引用
本申请要求在2022年10月25日提交中国专利局、申请号为202211310802.3、申请名称为“驱动单元、压电马达、摄像模组和电子设备”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及摄像技术领域，尤其涉及一种驱动单元、压电马达、摄像模组和电子设备。
背景技术
目前，电子设备(例如手机)的摄像模组的马达主要为音圈马达。音圈马达的电磁驱动力和磁场强度、线圈匝数正相关。
随着电子设备摄像技术的提升，摄像模组的感光芯片越来越大，镜头越来越重，并且自动对焦(auto focus，AF)的行程也越来越大。由于音圈马达的磁场作用范围有限，其难以满足大载重的摄像模组的AF大行程的需求。或者，为了适应大载重的摄像模组的AF大行程要求，就需要将音圈马达的磁铁和线圈增大，这就使得整个音圈马达的体积和重量变大，同时磁场强度的增大也会对相邻的磁性传感器带来磁干扰的问题。
发明内容
本申请提供了一种驱动单元、压电马达、摄像模组和电子设备，以增加摄像模组的自动对焦行程，提升电子设备的摄像效果。
第一方面，本申请提供一种驱动单元，该驱动单元可作为压电马达的驱动部件。驱动单元可以包括梁结构和压电材料层。其中，梁结构包括第一梁、第二梁和第三梁。第一梁包括第一面和第二面，且第一面和第二面相背设置，第二梁和第三梁可均位于第一面。另外，第二梁与第一梁相交设置，且第一梁和第二梁的连接处设置有第一驱动足，该第一驱动足可自第一梁和第二梁的连接处向背离第二梁的方向延伸。可以理解的是，该第一驱动足可作为驱动单元的驱动力的输出部位，这样可通过使第一驱动足与从动件连接，来实现驱动单元对从动件的驱动。压电材料层可设置于第一梁的第一面或第二面，又或者可在第一面和第二面均设置压电材料层。
采用本申请提供的驱动单元，可通过对压电材料层施加电信号来驱动第一梁和第二梁振动，从而在第一驱动足处输出驱动力和驱动位移。另外，通过对压电材料层持续施加同一电信号，可实现梁结构的持续振动，从而使其连续输出沿同一方向的驱动位移，这样可使驱动单元驱动从动件持续沿同一方向运动。则在将应用有该驱动单元的压电马达用于摄像模组时，可使驱动单元驱动镜头组件往复运动，从而可有效的增加摄像模组的对焦行程以及对焦精度。
在具体设置压电材料层时，可在沿第一面到第二面的方向上，使压电材料层包括层叠设置的多个压电陶瓷层，这样可有效的降低压电材料层的驱动电压，其可使驱动电路的设计成本得以降低。另外，压电材料层可沿层叠方向极化，则在对压电材料层施加沿极化方向的电场时，可使其能够产生沿极化方向的第一位移d33；并且产生沿垂直于第一位移d33方向的第二位移d31。其中，第一位移d33可用于激发第二梁和第三梁振动，该第二位移d31可用于激发第一梁振动。基于此，可通过对施加于压电材料层的电信号进行调整，即可对第一梁、第二梁以及第三梁的振动方向进行调节，从而实现对梁结构输出的驱动位移的调节，进而可实现驱动单元对从动件沿不同方向的驱动。
在本申请中，为了提高驱动单元的驱动效率，还可以是第一梁和第三梁的连接处设置有第二驱动足，该第二驱动足可与第一驱动足对称设置。这样，可以使第一驱动足和第二驱动足处均能够输出驱动力，其可使整个驱动单元输出的驱动力有效的增加。
另外，在本申请中，还可以使第二梁和第三梁对称设置。这样，在使第一驱动足和第二驱动足分别与从动件连接，其可使驱动单元在第一驱动足和第二驱动足处施加于从动件的预压力为一对平衡力，从而可有效的提高驱动单元的驱动效率。
在本申请一个可能的实现方式中，可以使压电材料层与第二梁之间的距离，与压电材料层与第三梁 之间的距离相等，这样可以使压电材料层驱动第二梁和第三梁产生对称的运动，从而使第二梁与第一梁的连接处，以及第三梁与第一梁的连接处输出对称的驱动力以及驱动位移。
在本申请一个可能的实现方式中，第一梁与第二梁之间的夹角为大于或等于30°，且小于或等于150°。示例性的，可以使第一梁与第二梁之间的夹角为90°，以使第一梁与第二梁在其振动方向上均具有较好的运动性能，从而可在第一梁与第二梁处输出较大的驱动力以及驱动位移。
相类似的，第一梁与第三梁之间的夹角也可以为大于或等于30°，且小于或等于150°。示例性的，可以使第一梁与第三梁之间的夹角为90°，以使第一梁与第三梁在其振动方向上均具有较好的运动性能，从而可在第一梁与第三梁处输出较大的驱动力以及驱动位移。
另外，在第一梁和第二梁的连接处可以设置有第一缺口，该第一缺口的开口朝向第一梁、第二梁和第三梁围成的区域设置。这样，可以在第一梁和第二梁的连接处形成柔性铰链结构，其可有效的降低第一梁和第二梁的连接刚性，以使第一梁和第二梁更易于发生形变。
相类似的，在第一梁和第三梁的连接处可以设置有第二缺口，该第二缺口的开口朝向第一梁、第二梁和第三梁围成的区域设置。这样，可以在第一梁和第三梁的连接处形成柔性铰链结构，其可有效的降低第一梁和第三梁的连接刚性，以使第一梁和第三梁更易于发生形变。
在本申请一个可能的实现方式中，梁结构的厚度方向的尺寸可以小于梁结构的长度方向和高度方向的尺寸；其中，长度方向为第一梁的延伸方向，高度方向为第一面到第二面的方向，厚度方向为与长度方向和高度方向均垂直的方向。这样可以使梁结构的振动更易于实现，从而使该驱动单元对于压电材料层的驱动信号等的设置要求更低，其有利于降低驱动成本。
在本申请一个可能的实现方式中，梁结构可以为一体成型结构。这样可以有效的提高梁结构的结构可靠性，并可降低梁结构的加工成本。
第二方面，本申请还提供一种压电马达，该压电马达可以包括马达基座、驱动单元、载体和预压弹片。其中，马达基座可包括容置腔。驱动单元可设置于容置腔，驱动单元包括梁结构和压电材料层，梁结构包括第一梁、第二梁和第三梁，第一梁包括相背设置的第一面和第二面，第二梁和第三梁位于第一面，第二梁与第一梁相交设置，且第一梁和第三梁相交设置。第一梁和第二梁的连接处设置有第一驱动足，第一梁和第三梁的连接处设置有第二驱动足，第二驱动足与第一驱动足对称设置。另外，压电材料层设置于第一面或第二面，或者在第一面和第二面均设置压电材料层。载体可设置于容置腔，预压弹片可与载体固定连接，并且预压弹片可包括第一抵接部和第二抵接部，第一抵接部可与第一驱动足相抵接，以使第一抵接部发生弹性变形并产生预压力。第二抵接部可与第二驱动足相抵接，以使第二抵接部发生弹性变形并产生预压力。
另外，载体可包括安装孔，驱动单元可用于驱动载体沿安装孔的轴线运动。具体实施时，当对压电材料层施加第一电信号时，驱动单元可带动载体沿第一方向运动；而当对压电材料层施加第二电信号时，驱动单元带动载体沿第二方向运动，其中，第一方向和第二方向相反，从而可实现驱动单元对载体的往返运动的驱动。
采用本申请提供的压电马达，可通过对压电材料层施加电信号来驱动第一梁、第二梁和第三梁振动，从而在第一驱动足和第二驱动足处输出驱动力和驱动位移。另外，通过对压电材料层持续施加同一电信号，可实现梁结构的持续振动，从而使其连续输出沿同一方向的驱动位移，这样可使驱动单元驱动载体持续沿同一方向运动。则在将该压电马达用于摄像模组时，可使驱动单元驱动镜头组件往复运动，从而可有效的增加摄像模组的对焦行程以及对焦精度。
在具体设置压电材料层时，可在沿第一面到第二面的方向上，使压电材料层包括层叠设置的多个压电陶瓷层，这样可有效的降低压电材料层的驱动电压，其可使驱动电路的设计成本得以降低。另外，压电材料层可沿层叠方向极化，则在对压电材料层施加沿极化方向的电场时，可使其能够产生沿极化方向的第一位移d33；并且产生沿垂直于第一位移d33方向的第二位移d31。其中，第一位移d33可用于激发第二梁和第三梁振动，该第二位移d31可用于激发第一梁振动。基于此，可通过对施加于压电材料层的电信号进行调整，即可对第一梁、第二梁以及第三梁的振动方向进行调节，从而实现对梁结构输出的驱动位移的调节，进而可实现驱动单元对从动件沿不同方向的驱动。
另外，在本申请中，还可以使第二梁和第三梁对称设置。这样，在使第一驱动足和第二驱动足分别与从动件连接，其可使驱动单元在第一驱动足和第二驱动足处施加于从动件的预压力为一对平衡力，从而可有效的提高驱动单元的驱动效率。
在本申请一个可能的实现方式中，可以使压电材料层与第二梁之间的距离，与压电材料层与第三梁之间的距离相等，这样可以使压电材料层驱动第二梁和第三梁产生对称的运动，从而使第二梁与第一梁的连接处，以及第三梁与第一梁的连接处输出对称的驱动力以及驱动位移。
在本申请一个可能的实现方式中，第一梁与第二梁之间的夹角为大于或等于30°，且小于或等于150°。示例性的，可以使第一梁与第二梁之间的夹角为90°，以使第一梁与第二梁在其振动方向上均具有较好的运动性能，从而可在第一梁与第二梁处输出较大的驱动力以及驱动位移。
相类似的，在本申请中，第一梁与第三梁之间的夹角也可以为大于或等于30°，且小于或等于150°。示例性的，可以使第一梁与第三梁之间的夹角为90°，以使第一梁与第三梁在其振动方向上均具有较好的运动性能，从而可在第一梁与第三梁处输出较大的驱动力以及驱动位移。
另外，在第一梁和第二梁的连接处可以设置有第一缺口，该第一缺口的开口朝向第一梁、第二梁和第三梁围成的区域设置。这样，可以在第一梁和第二梁的连接处形成柔性铰链结构，其可有效的降低第一梁和第二梁的连接刚性，以使第一梁和第二梁更易于发生形变。
相类似的，在第一梁和第三梁的连接处可以设置有第二缺口，该第二缺口的开口朝向第一梁、第二梁和第三梁围成的区域设置。这样，可以在第一梁和第三梁的连接处形成柔性铰链结构，其可有效的降低第一梁和第三梁的连接刚性，以使第一梁和第三梁更易于发生形变。
在本申请一个可能的实现方式中，梁结构的厚度方向的尺寸可以小于梁结构的长度方向和高度方向的尺寸；其中，长度方向为第一梁的延伸方向，高度方向为第一面到第二面的方向，厚度方向为与长度方向和高度方向均垂直的方向。这样可以使梁结构的振动更易于实现，从而使该驱动单元对于压电材料层的驱动信号等的设置要求更低，其有利于降低驱动成本。
在本申请一个可能的实现方式中，梁结构可以为一体成型结构。这样可以有效的提高梁结构的结构可靠性，并可降低梁结构的加工成本。
为了便于将驱动单元设置于压电马达，可以使压电马达还包括驱动单元基座，驱动单元基座设置有限位槽，并且驱动单元基座与马达基座固定连接。另外，梁结构还可以包括夹持梁，第二梁和第三梁相对于夹持梁对称设置，则夹持梁插设于限位槽，且夹持梁和驱动单元基座固定连接。此时，第二梁和第三梁为自由态，这样，在压电材料层的驱动下，第一梁、第二梁和第三梁可发生自由的弯曲以及伸缩变形。而又由于夹持梁与驱动单元基座固定连接，其可有效的提高驱动单元振动的稳定性。
在本申请中，马达基座可以包括多个挡板，该多个挡板可围设形成上述的容置腔。另外，多个挡板包括第一挡板，驱动单元基座可与第一挡板固定连接。这样，可以使驱动单元只设置于压电马达的一个挡板处，可使压电马达的结构较为紧凑，空间利用率较高，从而可利于实现压电马达的小型化设计。
在本申请一个可能的实现方式中，驱动单元基座和马达基座中的至少一个设置有第一磁性件，载体设置有第二磁性件，第一磁性件和第二磁性件相吸附。由于驱动单元只设置于压电马达的一侧，第一磁性件和第二磁性件相吸附产生的磁性力的力矩，可以与载体运动过程中的重力矩以及驱动单元的驱动力矩相平衡，从而可有效的提升压电马达的结构稳定性。
另外，载体还可以设置有导向机构，导向机构可位于载体的朝向第一挡板的一侧。导向机构包括安装部和导向件，安装部具有安装槽，导向件的部分容置于安装槽。第一挡板开设有导向槽，导向件的部分容置于导向槽。驱动单元驱动载体沿安装孔的轴向运动时，导向件沿导向槽运动，从而可为载体的运动提供导向的作用，其有利于提高载体运动的稳定性。
由上文的介绍可以知道，第一驱动足与第一抵接部相抵接产生的预压力，与第二驱动足与第二抵接部相抵接产生的预压力为一对平衡力。因此，导向机构无需提供额外的力来平衡预压力，其可有效的降低导向件运动过程中的摩擦阻力，从而使驱动单元的驱动效率得以提升。
在本申请中不对导向件的具体设置形式进行限定，其示例性的可为滚珠。这样，导向件在运动的过程中，其与导向槽之间的摩擦力为滚动摩擦力，从而可使导向件在运动的过程中的摩擦阻力较小。另外，导向件还可以为滑轴，该导向件在运动的过程中，其与导向槽之间的摩擦力为滑动摩擦力，为了减小导向件运动过程中的摩擦阻力，可以在滑轴的表面镀上润滑涂层或者涂抹润滑脂等来减小导向件与导向槽之间的摩擦系数。
为了保证载体运动的稳定性，可使导向机构为两个，驱动单元可位于两个导向机构之间，且两个导向机构可对称设置。
在本申请一个可能的实现方式中，压电马达还可以设置有驱动电路板，多个挡板还包括第二挡板， 驱动电路板设置于第二挡板，该第二挡板可以但不限于与第一挡板相邻设置。另外，驱动电路板设置有驱动电路，该驱动电路用于产生第一电信号和第二电信号。由上文的介绍可以知道，压电材料层的驱动电压较低，因此用于驱动该压电材料层的驱动电路较为简单，其可以但不限于为压电马达中已有的IC提供，从而可避免单独为压电材料层设置驱动电路，以降低驱动成本，并可使压电马达的体积较小。
为了使压电材料层能够被上述的驱动电路进行驱动，可以使压电材料层包括第一电极和第二电极。另外，驱动单元基座可设置有第一电极片和第二电极片，这样第一电极可通过第一电极片与驱动电路的第一输出端电连接，第二电极可通过第二电极片与驱动电路的第二输出端电连接。
第三方面，本申请还提供一种摄像模组，该摄像模组可以包括镜头组件以及第二方面的压电马达，镜头组件可以安装于载体的安装孔，则压电马达可驱动镜头组件沿镜头组件的光轴方向往复运动，从而可实现摄像模组的大行程的自动对焦。
第四方面，本申请还提供一种电子设备，包括壳体以及如第二方面的摄像模组，摄像模组设置于壳体的内部。其中，电子设备包括但不限于手机、平板电脑、笔记本电脑、手表、摄像头等设备。该电子设备的摄像模组可实现高精度、快响应、大行程、大载重以及抗震的自动对焦，因此，该电子设备具有较佳的摄像效果。
附图说明
图1为本申请一实施例提供的电子设备的结构示意图；
图2为本申请一实施例提供的摄像模组的结构示意图；
图3a为本申请一实施例提供的驱动单元的结构示意图；
图3b为本申请另一实施例提供的驱动单元的结构示意图；
图3c为本申请另一实施例提供的驱动单元的结构示意图；
图4为本申请一实施例提供压电材料层的俯视图；
图5为图4中所示压电材料层的A-A剖视图；
图6a为本申请一实施例提供的驱动电路的结构示意图；
图6b为图6a中的驱动电路产生的驱动信号；
图7a为本申请一实施例提供的驱动单元在第一工作模态下的振动方式；
图7b为本申请一实施例提供的驱动单元在第二工作模态下的振动方式；
图8为本申请一实施例提供的压电马达的爆炸图；
图9为图8中所示压电马达的组装结构示意图；
图10为本申请一实施例提供的驱动单元基座、驱动单元和预压弹片的连接关系示意图；
图11为图10所示结构的另一角度下的结构示意图；
图12为本申请一实施例提供的压电马达的局部结构示意图；
图13为本申请另一实施例提供的压电马达的局部结构示意图；
图14为本申请一实施例提供的摄像模组的爆炸图。
附图标记：
1-壳体；2-处理器；
3-摄像模组；301-镜头组件；302-压电马达；3021-驱动单元；30211-梁结构；
302111-第一梁；3021111-第一面；3021112-第二面；3021113-第一端；3021114-第二端；
302112-第二梁；302113-第三梁；302114-第一缺口；302115-第二缺口；
302116-第一驱动足；302117-第二驱动足；302118-夹持梁；
30212-压电材料层；302121-第一电极；3021211-第一外电极；3021212-第一内电极；
302122-第二电极；3021221-第二外电极；3021222-第二内电极；
3022-驱动单元基座；30221-限位槽；30222-第一搭接部；30223-第二搭接部；
30224-第一电极片；30225-第二电极片；30226-第一磁性件；
3023-马达基座；30231-容置腔；30232-第一挡板；302321-避让口；302322-第一减薄区；
302323-第二减薄区；302324-导向槽；30233-第一电路连接端口；
30234-第二电路连接端口；30235-驱动电路板；30236-第二挡板；
30237-载体；302371-第二磁性件；302372-导向机构；3023721-安装部；30237211-安装槽；
3023722-导向件；302373-安装孔；
30238-预压弹片；302381-第一抵接部；302382-第二抵接部；
303-外壳；3031-镜头孔；401-第一输出端；402-第二输出端。
具体实施方式
为了使本申请的目的、技术方案和优点更加清楚，下面将结合附图对本申请作进一步地详细描述。
以下实施例中所使用的术语只是为了描述特定实施例的目的，而并非旨在作为对本申请的限制。如在本申请的说明书和所附权利要求书中所使用的那样，单数表达形式“一个”、“一种”、“所述”、“上述”、“该”和“这一”旨在也包括例如“一个或多个”这种表达形式，除非其上下文中明确地有相反指示。
在本说明书中描述的参考“一个实施例”或“一些实施例”等意味着在本申请的一个或多个实施例中包括结合该实施例描述的特定特征、结构或特点。由此，在本说明书中的不同之处出现的语句“在一个实施例中”、“在一些实施例中”、“在其他一些实施例中”、“在另外一些实施例中”等不是必然都参考相同的实施例，而是意味着“一个或多个但不是所有的实施例”，除非是以其他方式另外特别强调。术语“包括”、“包含”、“具有”及它们的变形都意味着“包括但不限于”，除非是以其他方式另外特别强调。
为方便理解本申请提供的驱动单元、压电马达、摄像模组以及电子设备，下面首先对其应用场景进行解释说明。压电马达(又称超声波马达)，因其具有响应快、断电自锁、载重大、大行程等特性优点，逐步成为摄像领域研究的热点，以满足未来电子设备的摄像模组的对焦技术需求。其中，电子设备包括但不限于手机、平板电脑、笔记本电脑、电话手表、移动摄像装置等。图1为本申请提供的一种电子设备的结构示意图，以手机为例，该电子设备可包括壳体1和置于壳体1内部的处理器2、显示模组(图中未示出)和摄像模组3，除此之外，电子设备还可包括图中未示出的扬声器、受话筒、天线、麦克风等部件。壳体1还分为前盖板和后盖板，壳体1的前盖板和后盖板均可设置摄像模组3，以后盖板为例，后盖板上设有摄像孔，摄像模组3设于壳体1的内部，并通过后盖板的摄像孔采集光线，进行图像的拍摄。摄像模组3和显示模组均与处理器2电连接，处理器2控制摄像模组3进行拍摄，摄像模组3将采集的图像信息传递给处理器2，并在显示模组中进行图像的显示。
通常情况下，摄像模组3可包括镜头组件301和压电马达302，可参照图2，图2为本申请提供的一种摄像模组3的结构示意图。其中，镜头组件301安装于压电马达302的入光侧，压电马达302可驱动镜头组件301沿其光轴方向往复运动，其运动方向可用图2中的双向箭头表示，从而实现摄像模组3的自动对焦。随着摄像技术的提升，用户对于摄像模组3的自动对焦也提出了更高的要求，例如要求摄像模组3具有更大的自动对焦行程。
驱动单元作为压电马达中重要的驱动元件，其对镜头组件301的驱动效率对于应用有该压电马达302的摄像模组3的自动对焦的行程有着直接的影响。现有的压电马达，为了提高驱动单元的驱动效率，通常会为驱动单元单独设置相匹配的驱动电路，其导致驱动成本较高，并使摄像模组的体积增大。
本申请提供的驱动单元旨在解决上述问题，以通过对驱动单元的结构以及工作模态的设计，使驱动单元能够被电子设备中已有的驱动电路驱动，以在降低驱动成本的同时，还可以避免摄像模组的体积的增大。另外，该驱动单元在应用于压电马达时，可通过对驱动单元的驱动足的数量进行设计，以使驱动单元施加于镜头组件的预压力实现自平衡，其有利于驱动单元的驱动效率的提高，从而可有效的增加摄像模组的自动对焦行程，以使应用有该摄像模组的电子设备的摄像效果得以提升。为方便理解本申请实施例提供的驱动单元，下面结合附图对其具体结构进行详细的说明。
参照图3a，图3a为本申请一实施例提供的驱动单元3021的结构示意图。该驱动单元可以包括梁结构30211和压电材料层30212。其中，梁结构30211可以包括第一梁302111、第二梁302112和第三梁302113，第二梁302112和第三梁302113可位于第一梁302111的同一侧，例如可将第二梁302112和第三梁302113均设置于第一梁302111的第一面3021111。另外，在沿第一梁302111的延伸方向上，第一梁302111具有第一端3021113和第二端3021114。第二梁302112可与第一梁302111的第一端3021113连接，第三梁302113可与第一梁302111的第二端3021114连接。在本申请中，不对梁结构30211的材质进行具体限定，示例性的，梁结构30211的材质可为不锈钢或磷青铜等易发生形变的金属材质。另外，梁结构30211可为一体成型的结构，其有利于提高该梁结构30211的结构可靠性，并可降低梁结构30211的加工成本。当梁结构 30211为一体成型结构时，第一梁302111、第二梁302112和第三梁302113的材质可以相同。在其它一些可能的实施例中，第一梁302111、第二梁302112和第三梁302113还可以为分别形成的独立结构，再通过焊接等方式进行连接，此时，第一梁302111、第二梁302112和第三梁302113的材质可以相同，也可以不同。压电材料层30212可用于驱动梁结构30211的第一梁302111、第二梁302112和第三梁302113发生形变以产生振动，从而使梁结构30211能够输出驱动力以及驱动位移。
在具体设置梁结构30211时，仍以图3a所示的驱动单元3021为例，其中，第一梁302111与第二梁302112可相交设置。在本申请中，两个梁相交是指在二者的连接处存在一不为0的夹角α，该夹角α可以但不限于为大于或等于30°，且小于或等于150°。在本申请一个可能的实施例中，第一梁302111和第二梁302112在其连接处的夹角可为90°，此时可认为第一梁302111和第二梁302112成正交关系。通过将第一梁302111和第二梁302112成正交设置，能够使第一梁302111和第二梁302112分别在其延伸方向上均具有较好的运动性能，从而使其在运动方向上具有更大的驱动位移，以在每个驱动周期内的步进更大，并具有更高的运动速度。这样，可有效的缩短驱动单元3021的响应时间，从而在将应用有该驱动单元3021的压电马达302用于摄像模组3时，可有效的提高对焦的调节效率。
可继续参照图3a，第一梁302111与第二梁302112的连接处可设置有第一缺口302114，该第一缺口302114的开口可朝向第一梁302111、第二梁302112和第三梁302113围成的区域设置。通过在第一梁302111和第二梁302112的连接处设置第一缺口302114，可在该连接处形成柔性铰链结构，从而可有效的降低二者连接处的连接强度。这样可以使第一梁302111和第二梁302112在该连接处的振动位移增加，并可有利于其振动速度和输出的驱动力的增加。
另外，可继续参照图3a，第一梁302111与第三梁302113也可相交设置。且第一梁302111和第三梁302113的夹角也可以但不限于为大于或等于30°，且小于或等于150°。示例性的，第一梁302111和第二梁302112在其连接处的夹角可为90°，以使第一梁302111和第三梁302113成正交关系。从而可使第一梁302111和第三梁302113分别在其延伸方向上均具有较好的运动性能，以使其在运动方向上具有更大的驱动位移，并在每个驱动周期内的步进更大，运动速度更高。
相类似的，在第一梁302111和第三梁302113的连接处可设置有第二缺口302115，该第二缺口302115的开口可朝向第一梁302111、第二梁302112和第三梁302113围成的区域设置。通过在第一梁302111和第三梁302113的连接处设置第二缺口302115，可在该连接处形成柔性铰链结构，从而可有效的降低二者连接处的连接强度。这样可以使第一梁302111和第三梁302113在该连接处的振动位移增加，并可有利于其振动速度和输出的驱动力的增加。
在本申请中，可以使第二梁302112和第三梁302113对称设置，其有利于提高梁结构30211运动的稳定性。从而使该驱动单元3021输出的驱动力更加稳定，以在通过该驱动单元3021驱动如图2所示的镜头组件301运动时，有效的提高镜头组件301的运动平稳性。
由上文的介绍可以知道，在梁结构30211振动的过程中，可以在第一梁302111和第二梁302112的连接处形成驱动力和驱动位移。基于此，为了便于实现梁结构30211的驱动作用，可继续参照图3a，在第二梁302112与第一梁302111的连接处可设置有第一驱动足302116，该第一驱动足302116可位于第一梁302111、第二梁302112和第三梁302113围成的区域的外侧。另外，该第一驱动足302116可自第一梁302111和第二梁302112的连接处向背离第二梁302112的方向延伸。
可继续参照图3a，相类似的，在第三梁302113和第一梁302111的连接处也可以设置有第二驱动足302117，该第二驱动足302117可位于第一梁302111、第二梁302112和第三梁302113围成的区域的外侧。另外，该第二驱动足302117可自第一梁302111和第三梁302113的连接处向背离第三梁302113的方向延伸。
在本申请一个可能的实施例中，第一驱动足302116和第二驱动足302117可对称设置，从而可在梁结构30211振动的过程中，能够使第一驱动足302116和第二驱动足302117处产生的驱动力以及驱动位移对称。具体的，第一梁302111还可以包括第二面3021112，第一面3021111和第二面3021112相背设置。这样，在第一面3021111到第二面3021112，或者第二面3021112到第一面3021111的方向上，可以使第一驱动足302116处产生的驱动力的分力，与第二驱动足302117处产生的驱动力的分力大小相等，方向相同，从而使梁结构30211在该方向上能够输出稳定的驱动力以及驱动位移，并且还可以使驱动单元3021在该方向上具有较大的驱动力以及驱动位移。
可继续参照图3a，在本申请中，可以使梁结构30211在其厚度h方向上的尺寸，小于梁结构30211在其长度方向和高度方向上的尺寸。其中，梁结构30211的长度方向为第一梁302111的延伸方向。另外， 梁结构30211的高度方向可理解为第一面3021111到第二面3021112的方向。当第二梁302112和第三梁302113与第一梁302111正交设置时，梁结构30211的高度方向也为第二梁302112和第三梁302113自第一梁302111延伸的延伸方向。可以理解的是，梁结构30211的厚度方向与其长度方向和高度方向均垂直。另外，在本申请中，可使第一梁302111、第二梁302112和第三梁302113在厚度方向上的尺寸相同。
在本申请中，通过使梁结构30211的厚度方向的尺寸小于梁结构30211的长度方向和高度方向的尺寸，可以使梁结构30211的振动更易于实现，从而使该驱动单元3021对于压电材料层30212的驱动信号等的设置要求更低，其有利于降低驱动成本。
为了实现压电材料层30212对梁结构30211的振动的驱动，在本申请中，可将压电材料层30212设置于第一梁302111，其可以但不限于通过粘接或者焊接方式固定于第一梁302111。另外，本申请对于压电材料层30212在第一梁302111上的设置不做具体限定，例如在图3a所示的实施例中，压电材料层30212可设置于第一梁302111的第二面3021112。又如图3b所示，图3b为本申请另一实施例提供的驱动单元3021的结构示意图，此时压电材料层30212可设置于第一面3021111。另外，压电材料层30212可只在第一梁302111的一个面上设置，也可以在第一梁302111的两个面上分别进行设置，例如在图3c所示的驱动单元3021中，第一梁302111的第一面3021111和第二面3021112上均设置有压电材料层30212。除此之外，第一梁302111的一个面上可以只设置有一个压电材料层30212，也可以设置有两个或两个以上的压电材料层30212。
可以理解的是，为了使第二梁302112与第一梁302111的连接处，以及第三梁302113与第一梁302111的连接处产生对称的驱动力以及驱动位移，可以在将压电材料层30212设置于第一梁302111时，使压电材料层30212和第二梁302112之间的距离，与压电材料层30212和第三梁302113之间的距离相等。示例性的，当压电材料层30212为一个时，可将该一个压电材料层30212设置于第二梁302112和第三梁302113之间的中间位置，而当压电材料层30212为两个或两个以上时，可将该两个或两个以上压电材料层30212设置于第二梁302112和第三梁302113之间，且使该两个或两个以上的压电材料层30212对称设置。
由上文可知，压电材料层30212在梁结构30211上的设置位置对于梁结构30211的振动有着重要的影响。除此之外，压电材料层30212自身的结构设置以及压电材料层30212的驱动信号的选择也会对梁结构30211的振动产生影响。具体实施时，可参照图4，图4为本申请一实施例提供压电材料层30212的俯视图。在沿第一面3021111到第二面3021112的方向上，该压电材料层30212可以包括层叠设置的多个压电陶瓷层，其中，压电陶瓷层的材质可为有铅陶瓷或无铅陶瓷，有铅陶瓷例如可为锆钛酸铅系压电陶瓷，无铅陶瓷例如可为钛酸钡系压电陶瓷。通过使压电材料层30212包括多个压电陶瓷层，其可有利于降低该压电材料层30212的驱动电压，例如通过对压电材料层30212中的压电陶瓷层的层数进行设置，可实现对压电材料层30212的驱动电压的调整，示例性的可使驱动电压为2.8V～3.5V。又由于每层压电陶瓷的厚度可会对压电材料层30212的驱动电压产生影响，在本申请中，可以使每层压电陶瓷的厚度设置为5μm～50μm，示例性的可为15μm、20μm、31μm、40μm或45μm等，从而使压电材料层30212的驱动电压较低。
由于该驱动电压较低，其可由电子设备中已有的集成电路(integrated circuit，IC)提供，则无需为压电材料层30212单独设置驱动电路，其可有效的降低驱动成本，且可避免应用有该驱动单元的压电马达302的体积的增大，从而有利于实现压电马达302的小型化设计。
参照图5，图5为图4中所示压电材料层30212的A-A剖视图。该压电材料层30212包括第一电极302121和第二电极302122，其中，第一电极302121包括第一外电极3021211和第一内电极3021212，第二电极302122包括第二外电极3021221和第二内电极3021222。由图5可以看出，第一外电极3021211和第二外电极3021221设置于压电材料层30212的表面，第一内电极3021212和第二内电极3021222设置于压电材料层30212的内部。第一外电极3021211和第一内电极3021212电连接，第二外电极3021221和第二内电极3021222电连接。另外，在压电材料层30212的层叠方向上，第一内电极3021212和第二内电极3021222交替设置。基于此，压电材料层30212可沿其层叠方向极化，从而可在对该压电材料层30212施加沿极化方向的电场时，使其能够产生沿极化方向的第一位移d33；并且产生沿垂直于第一位移d33方向的第二位移d31。其中，第一位移d33可用于激发第二梁302112和第三梁302113振动，该第二位移d31可用于激发第一梁302111振动。
在本申请中，可通过对压电材料层30212的第一电极302121和第二电极302122施加一定频率的交流电信号来使其产生第一位移d33和第二位移d31。该交流电信号可以但不限于为正弦波、PWM波或者三 角波等。示例性的，考虑到在电子设备中，其IC的驱动电路可直接产生PWM波，因此可采用IC产生的PWM波对压电材料层30212进行驱动。
接下来以用于驱动压电材料层30212的电信号为PWM波为例，对压电材料层30212的驱动过程以及驱动单元的振动原理进行介绍。具体实施时，可参照图6a，图6a为本申请一实施例提供的驱动电路的结构示意图。该驱动电路可为IC提供的一个H桥，该H桥包括第一输出端401和第二输出端402。其中，第一输出端401可与图4或图5中所示压电材料层30212的第一电极302121电连接，第二输出端402可与图4或图5中所示压电材料层30212的第二电极302122电连接。
由于一个H桥可以产生两路驱动信号，可参照图6b，图6b展示了该H桥产生的两路驱动信号。在本申请中，可将H桥产生的驱动信号的信号频率记为f0。
另外，由上文对驱动单元3021的介绍可以知道，驱动单元3021在振动的过程中可产生驱动位移以及驱动力，而该驱动位移以及驱动力可用于驱动镜头组件301沿光轴方向往复运动。由此可知，驱动单元3021可具有两个工作模态，分别为第一工作模态和第二工作模态。其中，在第一工作模态和第二工作模态下，驱动单元3021可产生相反方向的驱动位移。示例性的，在第一工作模态下，驱动单元3021可驱动镜头组件301向靠近物像的方向运动，而在第二工作模态下，驱动单元3021可驱动镜头组件301向远离物像的方向运动。
在本申请中，为了使驱动单元3021产生振动，可以根据共振原理，使驱动信号的信号频率与驱动单元3021对应工作模态下的固有频率接近，从而使压电材料层30212和梁结构30211产生共振。具体实施时，可将驱动单元3021在第一工作模态下的固有频率记为f1，将驱动单元3021在第二工作模态下的固有频率记为f2。
当信号频率f0和固有频率f1接近时，可参照图7a，图7a为驱动单元3021在第一工作模态下的振动方式，此时，驱动单元3021的第一梁302111、第二梁302112和第三梁302113发生弯曲和伸缩变形，并且可在第一驱动足302116和第二驱动足302117处产生较强的振动。另外，可继续参照图7a，驱动单元3021在第一工作模态下振动时，第一驱动足302116处可产生一三象限的振动位移，此时，第一驱动足302116的运动方向可由图7a中的带双箭头的实线表示；第二驱动足302117处可产生二四象限的振动位移，此时，第二驱动足302117的运动方向可由图7a中的带双箭头的虚线表示。
当信号频率f0和固有频率f2接近时，可参照图7b，图7b为驱动单元3021在第二工作模态下的振动方式，此时，驱动单元3021的第一梁302111、第二梁302112和第三梁302113发生弯曲和伸缩变形，并且可在第一驱动足302116和第二驱动足302117处产生较强的振动。另外，可继续参照图7b，驱动单元3021在第二工作模态下振动时，第一驱动足302116处可产生二四象限的振动位移，此时，第一驱动足302116的运动方向可由图7a中的带双箭头的实线表示；第二驱动足302117处可产生一三象限的振动位移，此时，第二驱动足302117的运动方向可由图7a中的带双箭头的虚线表示。
在本申请中，可将H桥产生的驱动信号分别记为第一电信号和第二电信号，其中，第一电信号的信号频率f0与固有频率f1接近，第二电信号的信号频率f0与固有频率f2接近。基于此，可以通过切换驱动电路输出的驱动信号的信号频率来使驱动单元3021产生相反方向的振动，从而使驱动单元3021输出相反方向的驱动位移以及驱动力。该驱动电路的结构较为简单，其有利降低驱动成本。
另外，可以理解的是，当该驱动电路连续输出同一频率的驱动信号时，可以使驱动单元3021在该驱动信号的驱动下始终沿一个方向振动，从而在该方向上连续输出驱动力和驱动位移。这样，在将应用有该驱动单元3021的压电马达302用于摄像模组3时，可使驱动单元3021驱动镜头组件301沿一个方向持续运动，其有利于满足镜头组件301的大行程对焦的要求。
在对本申请提供的驱动单元3021进行了了解之后，接下来对该驱动单元3021在压电马达302中的具体设置方式进行介绍。可参照图8，图8为本申请一实施例提供的压电马达302的爆炸图。为了便于将驱动单元3021设置于压电马达302，可以使压电马达302包括驱动单元基座3022，该驱动单元基座3022可为驱动单元3021提供支撑以及限位的作用。另外，驱动单元基座3022可设置有限位槽30221，梁结构30211还可以包括夹持梁302118，第二梁302112和第三梁302113可相对于夹持梁302118对称设置。该夹持梁302118可插设于限位槽30221，且夹持梁302118与驱动单元基座3022固定连接，其连接方式可以但不限于为焊接或者粘接等。此时，驱动单元3021的第二梁302112和第三梁302113为自由态，这样，在压电材料层30212的驱动下，梁结构30211的第一梁302111、第二梁302112和第三梁302113可发生自由的弯曲以及伸缩变形。而又由于夹持梁302118与驱动单元基座3022固定连接，其可有效的提高驱动单元3021振动 的稳定性。
可继续参照图8，压电马达302还可以包括马达基座3023，在本申请中，不对马达基座3023的形状进行具体限定，其示例性的可为图8中所示的矩形框状结构。马达基座3023可以包括容置腔30231，驱动单元3021可容置于该容置腔30231。另外，驱动单元基座3022可与马达基座3023固定连接，具体实施时，马达基座3023还可以包括多个挡板，该多个挡板可围设形成上述的容置腔30231。该多个挡板可以包括第一挡板30232，这样，可以使第一挡板30232开设有避让口302321，从而可将驱动单元基座3022设置于该避让口302321，并使驱动单元基座3022与第一挡板30232固定连接，其连接方式可以但不限于焊接或者粘接等。
采用本申请提供的压电马达302，可将驱动单元3021只设置于马达基座3023的一个挡板处，其可使压电马达302的结构较为紧凑，空间利用率较高，从而可利于实现压电马达302的小型化设计。
可以理解的是，为了便于实现驱动单元基座3022和第一挡板30232的固定连接，可以使第一挡板30232的位于避让口302321两侧的部分进行减薄设计，以在第一挡板30232上形成第一减薄区302322和第二减薄区302323。同时可使驱动单元基座3022包括第一搭接部30222和第二搭接部30223。可参照图9，图9为图8中所示压电马达302的组装结构示意图。在将驱动单元基座3022固定于第一挡板30232时，可以使第一搭接部30222搭接于第一减薄区302322，使第二搭接部30223搭接于第二减薄区302323，并使第一搭接部30222和第一减薄区302322固定连接，第二搭接部30223和第二减薄区302323固定连接。另外，还可以使除第一减薄区302322和第二减薄区302323外，第一挡板30232其余部分的背离容置腔30231的表面，与第一搭接部30222和第二搭接部30223的背离容置腔30231的表面相平齐，以使驱动单元基座3022具有较为平整的外表面。
可继续参照图8和图9，为了使压电材料层30212的第一电极302121和第二电极302122能够与驱动电路连接，驱动单元基座3022可设置有第一电极片30224和第二电极片30225。在本申请中，不对第一电极片30224和第二电极片30225的具体设置方式进行限定，其示例性的可为具有导电性能的金属弹片，也可以为柔性电路板(flexible printed circuit，FPC)等。这样，第一电极片30224可与第一电极302121导电接触，第二电极片30225可与第二电极302122导电接触。另外，第一电极片30224可与如图6a所示的驱动电路的第一输出端401电连接，第二电极片30225可与驱动电路的第二输出端402电连接，从而实现压电材料层30212与驱动电路的电连接。其中，第一电极片30224与驱动电路的第一输出端401，以及第二电极片30225与驱动电路的第二输出端402可直接连接也可以间接连接，在本申请中不进行具体限定。
在本申请中，为了使第一电极片30224与驱动电路的第一输出端401电连接，第二电极片30225与驱动电路的第二输出端402电连接。可继续参照图8，马达基座3023上可以设置有第一电路连接端口30233和第二电路连接端口30234，第一电路连接端口30233可与第一输出端401电连接，第二电路连接端口30234可与第二输出端402电连接。另外，第一电路连接端口30233与第一电极片30224对应设置，第二电路连接端口30234与第二电极片30225对应设置。这样，在将驱动单元基座3022固定于马达基座3023时，第一电极片30224可与第一电路连接端口30233导电接触，第二电极片30225可与第二电路连接端口30234导电接触，从而实现压电材料层30212与驱动电路的电连接。
可继续参照图8，压电马达302还可以设置有驱动电路板30235，该驱动电路板30235可以但不限于为印制电路板(printed circuit board，PCB)或FPC。驱动电路板30235可设置于马达基座3023的一个挡板上，示例性的，驱动电路板30235可设置于马达基座3023的第二挡板30236上，其中，第二挡板30236与第一挡板30232可以相邻设置。另外，驱动电路板30235上可设置有IC，该IC可用于为压电材料层30212提供驱动电路，即该驱动电路可产生第一电信号和第二电信号。
可继续参照图8和图9，在本申请中，压电马达302还可以包括载体30237和预压弹片30238，载体30237和预压弹片30238可容置于容置腔30231内，且载体30237和预压弹片30238固定连接。载体30237具有安装孔302373，载体30237可在容置腔30231中沿安装孔302373的轴向往复运动。另外，载体30237可作为如图2中所示的镜头组件301的承载部件，镜头组件301可安装于安装孔302373，载体30237在运动的过程中可带动镜头组件301沿安装孔302373的轴向往复运动，从而实现镜头组件301沿其光轴方向的往复运动。
为了实现载体30237的运动，可参照图10，图10展示了预压弹片30238与驱动单元3021之间的连接关系。预压弹片30238具有第一抵接部302381和第二抵接部302382，其中，第一驱动足302116可与第一抵接部302381相抵接，以使第一抵接部302381发生弹性变形并产生预压力；第二驱动足302117可与第二抵接部302382相抵接，以使第一抵接部302381发生弹性变形并产生预压力。这样，在驱动单元3021振动的 过程中，其产生的驱动力可作用于预压弹片30238，从而可驱动载体30237沿安装孔302373的轴向往复运动。具体实施时，可在对图8中所示的驱动单元3021的压电材料层30212施加第一电信号时，使驱动单元3021带动载体30237沿第一方向运动；而在对压电材料层30212施加第二电信号时，可使驱动单元3021带动载体30237沿第二方向运动，其中，第一方向和第二方向为沿安装孔302373的轴向相反的两个方向。
另外，由上文对驱动单元3021的介绍可以知道，通过将第一驱动足302116和第二驱动足302117对称设置，可以使第一驱动足302116和第二驱动足302117处产生的驱动力以及驱动位移对称。基于此，第一驱动足302116与第一抵接部302381相抵接产生的预压力，与第二驱动足302117与第二抵接部302382相抵接产生的预压力可为一对平衡力。
可参照图11，图11为图10中所示结构在另一角度下的结构示意图。图11展示了驱动单元基座3022朝向如图8所示的容置腔30231一侧的结构设置，在本申请中，驱动单元基座3022还可以设置有第一磁性件30226，该第一磁性件30226可为一个，该一个磁性件可设置于驱动单元基座3022的中间部位。另外，第一磁性件30226也可为两个或两个以上，例如在图11所示的实施例中，第一磁性件30226为两个，该两个第一磁性件30226分设于限位槽30221的两侧，另外，该两个第一磁性件30226可相对于限位槽30221对称设置。
参照图12，图12为压电马达302的局部结构示意图。在本申请中，载体30237还可以设置有第二磁性件302371，该第二磁性件302371可设置于载体30237的朝向如图9所示的驱动单元3021的一侧。第二磁性件302371和第一磁性件30226可相互吸附，其中，第一磁性件30226和第二磁性件302371的数量可以相同，例如均为两个，从而可使第一磁性件30226和第二磁性件302371一一对应的吸附。
由于驱动单元3021只设置于压电马达302的一侧，第一磁性件30226和第二磁性件302371相吸附产生的磁性力的力矩，可以与载体30237运动过程中的重力矩以及驱动单元3021的驱动力矩相平衡，从而可有效的提升压电马达302的结构稳定性。
可以理解的是，第一磁性件30226除了可以设置于驱动单元基座3022外，还可以设置于马达基座3023，也可以理解为可以在驱动单元基座3022和马达基座3023中的至少一个上设置有第一磁性件30226，只要能够通过第一磁性件30226与第二磁性件302371的磁吸，起到平衡驱动单元3021的驱动力以及载体30237各运动状态下的重力的作用即可。另外，在本申请中，第一磁性件30226和第二磁性件302371可以为具有磁性的结构件，例如磁石等；也可以为能够被具有磁性的结构件吸附，而自身不具有磁性的结构件，例如材质为铁的结构件。
可继续参照图12，载体30237还可以设置有导向机构302372，该导向机构302372可位于载体30237的朝向第一挡板30232的一侧。其中，导向机构302372可包括安装部3023721以及导向件3023722，安装部3023721具有安装槽30237211，导向件3023722的部分容置于安装槽30237211内。另外，第一挡板30232的朝向容置腔30231的一侧开设有导向槽302324，导向件3023722的部分可容置于导向槽302324内。驱动单元3021驱动载体30237运动的过程中，导向件3023722可在导向槽302324内运动，从而为载体30237的运动提供导向作用，其有利于提高载体30237运动的稳定性。
另外，由于第一磁性件30226也设置于载体30237的朝向第一挡板30232的一侧，第二磁性件302371位于载体30237的朝向第一挡板30232的一侧，则第一磁性件30226和第二磁性件302371之间的吸附力还可以使载体30237将导向件3023722压向导向槽302324，从而可使第一磁性件30226与第二磁性件302371之间的磁性力，与载体30237由于自重所产生的相对于载体30237和导向件3023722接触点的重力矩相平衡，其有利于提高载体30237沿第一方向和第二方向运动的稳定性。
在本申请中，为了保证载体30237运动的稳定性，可使导向机构302372为两个，驱动单元3021可位于两个导向机构302372之间，并且该两个导向机构302372可对称设置。本申请不对导向件3023722的具体设置形式进行限定，例如在图12所示的实施例中，导向件3023722可为滚珠，另外，滚珠的数量可根据导向槽302324的延伸长度进行选择，例如在图12所示的实施例中，一个导向槽302324内设置有三个滚珠，则导向件3023722在运动的过程中，其与导向槽302324之间的摩擦力为滚动摩擦力，从而可使导向件3023722在运动的过程中的摩擦阻力较小。又如在图13所示的实施例中，导向件3023722还可以为滑轴，该导向件3023722在运动的过程中，其与导向槽302324之间的摩擦力为滑动摩擦力，为了减小导向件3023722运动过程中的摩擦阻力，可以在滑轴的表面镀上润滑涂层或者涂抹润滑脂等来减小导向件3023722与导向槽302324之间的摩擦系数。
由上文的介绍可以知道，第一驱动足302116与第一抵接部302381相抵接产生的预压力，与第二驱动 足302117与第二抵接部302382相抵接产生的预压力为一对平衡力。因此，导向机构302372无需提供额外的力来平衡预压力，其可有效的降低导向件3023722运动过程中的摩擦阻力，从而使驱动单元3021的驱动效率得以提升。
本申请上述实施例提供的压电马达302可用于各种摄像模组3，示例性的，可参照图14，图14为本申请一实施例提供的摄像模组3的爆炸图。图14所示的摄像模组3既可以作为电子设备的前置摄像头，也可为作为电子设备的后置摄像头，在此不做严格的限定。如图14所示，摄像模组3可包括镜头组件301和压电马达302，其中，镜头组件301可安装于压电马达302的入光侧，具体的，镜头组件301可安装于载体30237。从而可使压电马达302驱动镜头组件301沿镜头组件301的光轴方向往复运动，以实现摄像模组3的自动对焦。
可继续参照图14，摄像模组3还可以包括外壳303，外壳303可扣设于压电马达302，且外壳303可与马达基座3023的外边缘连接。另外，为便于对摄像模组3进行检修，可使外壳303与马达基座3023可拆卸连接，其连接方式可以但不限于为卡接。为便于镜头组件301接收光信号，外壳303还具有一镜头孔3031，镜头组件301的至少部分可由该镜头孔3031伸出至外壳303的外部。
除了上述结构外，摄像模组3还可以包括图像传感器(图14中未示出)等，图像传感器可固定于电路板且与电路板电连接，该电路板可以但不限于为上述图8中所示的驱动电路板30235。图像传感器用于接收自镜头组件301汇聚的光信号，并将光信号转换为电信号，形成的电信号可通过电路板传输至电子设备的处理器2。
本申请提供的摄像模组3，由于其压电马达302可实现高精度、快响应、大行程(>5mm)、大载重(g级)、抗震颤甚至无震颤的自动对焦，因此，应用有该摄像模组3的电子设备可具有较佳的摄像效果，其有利于提升电子设备的产品竞争力。
以上，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到变化或替换，都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以权利要求的保护范围为准。

Claims (29)

  1. 一种驱动单元，其特征在于，包括梁结构和压电材料层，其中：
    所述梁结构包括第一梁、第二梁和第三梁，所述第一梁包括相背设置的第一面和第二面，所述第二梁和所述第三梁位于所述第一面，所述第二梁与所述第一梁相交设置；所述第一梁和所述第二梁的连接处设置有第一驱动足，且自所述第一梁和所述第二梁的连接处，所述第一驱动足向背离所述第二梁的方向延伸；
    所述压电材料层设置于所述第一面和/或所述第二面。
  2. 如权利要求1所述的驱动单元，其特征在于，沿所述第一面到所述第二面的方向上，所述压电材料层包括层叠设置的多个压电陶瓷层，且所述压电材料层沿层叠方向极化。
  3. 如权利要求1或2所述的驱动单元，其特征在于，所述第一梁和所述第三梁的连接处设置有第二驱动足，所述第二驱动足与所述第一驱动足对称设置。
  4. 如权利要求1～3任一项所述的驱动单元，其特征在于，所述第二梁和所述第三梁对称设置。
  5. 如权利要求1～4任一项所述的驱动单元，其特征在于，所述压电材料层和所述第二梁之间的距离，与所述压电材料层与所述第三梁之间的距离相等。
  6. 如权利要求1～5任一项所述的驱动单元，其特征在于，所述第一梁与所述第二梁之间的夹角为大于或等于30°，且小于或等于150°；和/或，所述第一梁与所述第三梁之间的夹角为大于或等于30°，且小于或等于150°。
  7. 如权利要求6所述的驱动单元，其特征在于，所述第一梁与所述第二梁之间的夹角为90°；和/或，所述第一梁与所述第三梁之间的夹角为90°。
  8. 如权利要求1～7任一项所述的驱动单元，其特征在于，所述第一梁和所述第二梁的连接处设置有第一缺口，所述第一缺口的开口朝向所述第一梁、所述第二梁和所述第三梁围成的区域设置；
    所述第一梁和所述第三梁的连接处设置有第二缺口，所述第二缺口的开口朝向所述第一梁、所述第二梁和所述第三梁围成的区域设置。
  9. 如权利要求1～8任一项所述的驱动单元，其特征在于，所述梁结构的厚度方向的尺寸小于所述梁结构的长度方向和高度方向的尺寸；其中，所述长度方向为所述第一梁的延伸方向，所述高度方向为所述第一面到所述第二面的方向，所述厚度方向为与所述长度方向和所述高度方向均垂直的方向。
  10. 如权利要求1～9任一项所述的驱动单元，其特征在于，所述梁结构为一体成型结构。
  11. 一种压电马达，其特征在于，包括马达基座、驱动单元、载体和预压弹片，其中：
    所述马达基座包括容置腔；
    所述驱动单元设置于所述容置腔，所述驱动单元包括梁结构和压电材料层，所述梁结构包括第一梁、第二梁和第三梁，所述第一梁包括相背设置的第一面和第二面，所述第二梁和所述第三梁位于所述第一面，所述第二梁与所述第一梁相交设置，所述第二梁与所述第一梁相交设置；所述第一梁和所述第二梁的连接处设置有第一驱动足；所述第一梁和所述第三梁的连接处设置有第二驱动足，所述第二驱动足与所述第一驱动足对称设置；
    所述压电材料层设置于所述第一面和/或所述第二面；
    所述载体设置于所述容置腔，所述载体包括安装孔，所述驱动单元用于驱动所述载体沿所述安装孔的轴向运动；
    所述预压弹片与所述载体固定连接，且所述预压弹片包括第一抵接部和第二抵接部，所述第一抵接部与所述第一驱动足相抵接，并使所述第一抵接部发生弹性变形；所述第二抵接部与所述第二驱动足相抵接，并使所述第二抵接部发生弹性变形；
    当对所述压电材料层施加第一电信号时，所述驱动单元带动所述载体沿第一方向运动；当对所述压电材料层施加第二电信号时，所述驱动单元带动所述载体沿第二方向运动；其中，所述第一方向和所述第二方向相反。
  12. 如权利要求11所述的压电马达，其特征在于，沿所述第一面到所述第二面的方向上，所述压电材料层包括层叠设置的多个压电陶瓷层，且所述压电材料层沿层叠方向极化。
  13. 如权利要求11或12所述的压电马达，其特征在于，所述第二梁和所述第三梁对称设置。
  14. 如权利要求11～13任一项所述的压电马达，其特征在于，所述压电材料层和所述第二梁之间的距 离，与所述压电材料层与所述第三梁之间的距离相等。
  15. 如权利要求11～14任一项所述的压电马达，其特征在于，所述第一梁与所述第二梁之间的夹角为大于或等于30°，且小于或等于150°；和/或，所述第一梁与所述第三梁之间的夹角为大于或等于30°，且小于或等于150°。
  16. 如权利要求11～15任一项所述的压电马达，其特征在于，所述第一梁与所述第二梁之间的夹角为90°；和/或，所述第一梁与所述第三梁之间的夹角为90°。
  17. 如权利要求11～16任一项所述的压电马达，其特征在于，所述第一梁和所述第二梁的连接处设置有第一缺口，所述第一缺口的开口朝向所述第一梁、所述第二梁和所述第三梁围成的区域设置；
    所述第一梁和所述第三梁的连接处设置有第二缺口，所述第二缺口的开口朝向所述第一梁、所述第二梁和所述第三梁围成的区域设置。
  18. 如权利要求11～17任一项所述的压电马达，其特征在于，所述梁结构的厚度方向的尺寸小于所述梁结构的长度方向和高度方向的尺寸；其中，所述长度方向为所述第一梁的延伸方向，所述高度方向为沿所述第一面到所述第二面的方向，所述厚度方向为与所述长度方向和所述高度方向均垂直的方向。
  19. 如权利要求11～18任一项所述的压电马达，其特征在于，所述梁结构为一体成型结构。
  20. 如权利要求11～19任一项所述的压电马达，其特征在于，所述压电马达还包括驱动单元基座，所述驱动单元基座设置有限位槽，所述驱动单元基座与所述马达基座固定连接；
    所述梁结构还包括夹持梁，所述第二梁和所述第三梁相对于所述夹持梁对称设置，所述夹持梁插设于所述限位槽，所述夹持梁和所述驱动单元基座固定连接。
  21. 如权利要求20所述的压电马达，其特征在于，所述马达基座包括多个挡板，多个所述挡板围设形成所述容置腔；多个所述挡板包括第一挡板，所述驱动单元基座与所述第一挡板固定连接。
  22. 如权利要求21所述的压电马达，其特征在于，所述驱动单元基座和所述马达基座中的至少一个设置有第一磁性件，所述载体设置有第二磁性件，所述第一磁性件和所述第二磁性件相吸附。
  23. 如权利要求22所述的压电马达，其特征在于，所述载体还可以设置有导向机构，所述导向机构位于所述载体的朝向所述第一挡板的一侧；所述导向机构包括安装部和导向件，所述安装部具有安装槽，所述导向件的部分容置于所述安装槽；
    所述第一挡板开设有导向槽，所述导向件的部分容置于所述导向槽；所述驱动单元驱动所述载体沿所述安装孔的轴向运动时，所述导向件沿所述导向槽运动。
  24. 如权利要求23所述的压电马达，其特征在于，所述导向件为滚珠或滑轴。
  25. 如权利要求23或24所述的压电马达，其特征在于，所述导向机构为两个，所述驱动单元位于两个所述导向机构之间，且两个所述导向机构对称设置。
  26. 如权利要求21～25任一项所述的压电马达，其特征在于，所述压电马达还可以设置有驱动电路板，多个所述挡板还包括第二挡板，所述驱动电路板设置于所述第二挡板；所述驱动电路板设置有驱动电路，所述驱动电路用于产生所述第一电信号和所述第二电信号。
  27. 如权利要求26所述的压电马达，其特征在于，所述压电材料层包括第一电极和第二电极，所述驱动单元基座设置有第一电极片和第二电极片；所述第一电极通过所述第一电极片与所述驱动电路的第一输出端电连接，所述第二电极通过所述第二电极片与所述驱动电路的第二输出端电连接。
  28. 一种摄像模组，其特征在于，包括镜头组件以及如权利要求11-27任一项所述的压电马达，其中，所述镜头组件安装于所述载体的所述安装孔。
  29. 一种电子设备，其特征在于，包括壳体以及如权利要求28所述的摄像模组，所述摄像模组设置于所述壳体的内部。
PCT/CN2023/120171 2022-10-25 2023-09-20 驱动单元、压电马达、摄像模组和电子设备 WO2024087956A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202211310802.3 2022-10-25
CN202211310802.3A CN117977999A (zh) 2022-10-25 2022-10-25 驱动单元、压电马达、摄像模组和电子设备

Publications (1)

Publication Number Publication Date
WO2024087956A1 true WO2024087956A1 (zh) 2024-05-02

Family

ID=90829948

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2023/120171 WO2024087956A1 (zh) 2022-10-25 2023-09-20 驱动单元、压电马达、摄像模组和电子设备

Country Status (2)

Country Link
CN (1) CN117977999A (zh)
WO (1) WO2024087956A1 (zh)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101071995A (zh) * 2007-06-14 2007-11-14 南京航空航天大学 双驱动足纵振模态叠加式直线型超声电机及工作模态和电激励方式
US10744532B1 (en) * 2016-05-06 2020-08-18 Image Acoustics, Inc. End driven bender transduction apparatus
CN112859535A (zh) * 2021-01-11 2021-05-28 西安交通大学 一种桥式差动柔性位移缩小机构
CN113459053A (zh) * 2021-06-25 2021-10-01 西安交通大学 一种基于压电驱动的运动平台装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101071995A (zh) * 2007-06-14 2007-11-14 南京航空航天大学 双驱动足纵振模态叠加式直线型超声电机及工作模态和电激励方式
US10744532B1 (en) * 2016-05-06 2020-08-18 Image Acoustics, Inc. End driven bender transduction apparatus
CN112859535A (zh) * 2021-01-11 2021-05-28 西安交通大学 一种桥式差动柔性位移缩小机构
CN113459053A (zh) * 2021-06-25 2021-10-01 西安交通大学 一种基于压电驱动的运动平台装置

Also Published As

Publication number Publication date
CN117977999A (zh) 2024-05-03

Similar Documents

Publication Publication Date Title
US8279541B2 (en) Lens actuator module
WO2022007182A1 (zh) 镜头模组
US8040623B2 (en) Compact auto focus lens module with piezoelectric actuator
KR100927420B1 (ko) 렌즈 구동 모듈
WO2023025027A1 (zh) 摄像头模组和电子设备
WO2024087956A1 (zh) 驱动单元、压电马达、摄像模组和电子设备
WO2022228111A1 (zh) 摄像模组
WO2023202510A1 (zh) 压电马达、摄像模组和电子设备
JP2013254184A (ja) 手振れ補正機能付きカメラモジュールを搭載した電子機器
WO2023197994A1 (zh) 驱动组件和电子设备
WO2022033356A1 (zh) 超声波压电马达、摄像头模组及电子设备
WO2022143651A1 (zh) 压电马达、摄像模组及电子设备
WO2024037631A1 (zh) 压电马达及其摄像模组
WO2024104098A1 (zh) 一种压电马达、摄像模组和电子设备
CN219999459U (zh) 一种摄像头模组和电子设备
WO2024093316A1 (zh) 摄像马达、摄像模组及电子设备
WO2024001378A1 (zh) 一种压电马达及其摄像模组
WO2022214084A1 (zh) 潜望式摄像模组和可变焦摄像模组
CN217932225U (zh) 镜头模组、摄像头模组以及电子设备
CN114885088A (zh) 摄像模组及其光学防抖方法和电子设备
CN117440227A (zh) 一种压电马达及其摄像模组
CN115268167A (zh) 摄像模组
CN114942504A (zh) 可变焦摄像模组
CN117440229A (zh) 一种压电马达及其摄像模组
CN117440228A (zh) 一种压电马达及其摄像模组