CN117676282A - Piezoelectric motor and camera module thereof - Google Patents

Abstract

The application provides a piezoelectric motor, which is characterized by comprising a fixed assembly, a movable carrier, a piezoelectric actuator and a guide mechanism. The fixed component comprises a base, a shell and the like, the movable carrier is arranged above the base, the guide mechanism maintains the parallelism of the piezoelectric vibrator and the movable carrier, the piezoelectric actuator comprises a piezoelectric vibrator, a spring piece and the like, one surface of the spring piece is arranged on one surface of the piezoelectric vibrator, and the other surface of the spring piece is connected with the shell; the elastic sheet is abutted against the piezoelectric vibrator, and the elastic sheet is contacted with two rectangular short sides of the piezoelectric vibrator; the rectangular long side of the elastic piece is perpendicular to the rectangular long side of the piezoelectric vibrator.

Description

Piezoelectric motor and camera module thereof

Technical Field

This scheme belongs to the module technical field of making a video recording, especially relates to a module of making a video recording with piezoelectricity motor structure.

Background

Currently, a camera module in a mobile phone terminal generally includes: optical elements, actuators, filter elements and image sensors. Optical elements often include optical lenses, optical barrels, and the like. Typically in camera modules, when movement is detected by a sensor, the actuator is operated to cause translational movement of the optical element to compensate the imaging beam, i.e. to compensate for displacement (linear and/or angular displacement) resulting from the movement. In order to meet the trend of the miniaturization of portable electronic devices, the industry has attempted to apply actuators widely used in the fields of medical treatment, industry, microscopy, cameras, etc. to small-sized camera modules, but there are still great challenges in applying existing actuators to small-sized camera modules that can be mass-produced due to the complicated structure and large volume of the existing actuators compared to small-sized camera modules that are disposed in portable electronic devices.

In recent years, with rapid development and improvement of various functions of portable electronic devices, an imaging module, which is one of important components of the portable electronic devices, has also been developed in design and application. The requirements of users on the size of the camera module are higher and higher, and the users expect the camera module which has high pixels, small size and zoom and anti-shake capabilities. However, in general, the higher the pixel, the larger the number of optical elements, the larger the total mechanical height (total track length, TTL) of the optical elements, the larger the load bearing of the motor required for the optical elements, and the motor size is also increasing. In the prior art, a voice coil type spring motor exists, but due to the problem of spring bearing capacity, the spring cannot well hold a large-size and heavy-weight optical element. In the prior art, a ball motor also exists, but the ball motor has a complex structure, does not have a mechanical reset element, and is easy to cause abnormal sound and the like. Therefore, the piezoelectric motor is used in the field of camera modules to solve most of the problems, but as the piezoelectric motor is used as a contact type actuator scheme, after the piezoelectric motor is in friction connection with a driven piece, the piezoelectric motor is driven by the driven piece to move, and the contact type design particularly needs to pay attention to the yield in the assembly process, the reliability in the use process, the performance of product representation and the miniaturization of the size, so that the scheme of the piezoelectric motor needs to be designed to achieve more performance.

In view of the above problems, the present invention provides an imaging module of a piezoelectric motor, which realizes a high-precision zooming effect by adopting a piezoelectric actuator, also avoids further enlargement of the size of the whole motor, reduces the size of the imaging module, improves the reliability of the piezoelectric motor, and optimizes the mounting yield of the piezoelectric motor by structural improvement, so as to solve at least one of the problems described above.

Disclosure of Invention

Further objects and advantages of the present invention will become fully apparent from the following description and the accompanying drawings.

It is an object of the present invention to provide a piezoelectric motor which overcomes the disadvantages of the prior art, and which is designed to achieve at least one of a convenient assembly, a compact size, and excellent mechanical reliability.

According to one aspect of the present invention, there is provided a piezoelectric motor, comprising:

the fixing assembly comprises a base and a shell, wherein the shell is positioned above the base;

a movable carrier disposed above the base;

the piezoelectric actuator comprises a piezoelectric vibrator and a spring plate, wherein one surface of the spring plate is arranged on one surface of the piezoelectric vibrator, and the other surface of the spring plate is connected with the shell; the elastic sheet is abutted against the piezoelectric vibrator, and the elastic sheet is contacted with two rectangular short sides of the piezoelectric vibrator; the rectangular long side of the elastic piece is perpendicular to the rectangular long side of the piezoelectric vibrator.

And a guide mechanism that maintains parallelism of the piezoelectric vibrator and the movable carrier.

According to an embodiment of the invention, wherein the piezoelectric actuator further comprises: the piezoelectric friction head is arranged at the center of one surface of the piezoelectric vibrator.

According to an embodiment of the invention, wherein the piezoelectric actuator further comprises: and the piezoelectric friction plate is abutted with the piezoelectric friction head.

According to one embodiment of the invention, the piezoelectric friction plate is arranged in parallel with one surface of the piezoelectric vibrator, and the piezoelectric friction head is located at the center of the piezoelectric friction plate.

According to one embodiment of the invention, the elastic sheet is provided with an elastic sheet frame, the middle area of the elastic sheet frame is of a rectangular hollow structure, and the size of the elastic sheet frame is larger than the area size of the surface of the piezoelectric vibrator.

According to one embodiment of the invention, the spring frame of the spring provides a pre-compression force on at least two rectangular short sides of the piezoelectric vibrator.

According to one embodiment of the invention, the pre-pressing edge of the elastic sheet, which is attached to the piezoelectric vibrator, is parallel to the driving direction of the piezoelectric vibrator.

According to one embodiment of the present invention, the spring further includes at least one spring extension arm, the spring extension arm has a groove structure, and the spring extension arm is embedded in the housing and keeps a certain gap with the housing.

According to one embodiment of the invention, the elastic piece is further provided with at least one elastic piece positioning hole, the elastic piece is fixed on the piezoelectric vibrator through the elastic piece positioning hole, and the elastic piece positioning hole is located at the position where the amplitude of the piezoelectric vibrator in the rectangular long side direction is minimum.

According to one embodiment of the present invention, the fixing assembly further includes an FPC board, the FPC board is disposed on the groove structure of the spring extension arm, and the FPC board is attached to the spring.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the appended claims.

Drawings

Fig. 1 shows a schematic diagram of the overall structure of the camera module in the present application.

Fig. 2 shows a schematic cross-sectional view of the camera module in the present application.

Fig. 3 shows a schematic cross-sectional view of a piezoelectric motor in the present application.

Fig. 4 shows an exploded schematic view of the piezoelectric motor in the present application.

Fig. 5 shows an exploded view of another angle of the piezoelectric motor in the present application.

Fig. 6 shows a schematic cross-sectional view of a first end face of a piezoelectric vibrator in the present application.

Fig. 7 shows a schematic diagram of an electrical signal waveform of the piezoelectric vibrator in the present application.

Fig. 8 shows a schematic view of an electrode structure of a piezoelectric vibrator in the present application.

Fig. 9 shows a schematic side view of the piezoelectric vibrator in the present application.

The above and other objects, features and advantages of the present invention will become more apparent by describing embodiments of the present invention in more detail with reference to the attached drawings. The accompanying drawings are included to provide a further understanding of embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, and not constitute a limitation to the invention. In the drawings, like reference numerals generally refer to like parts or steps.

Detailed Description

Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. It should be apparent that the described embodiments are only some embodiments of the present invention and not all embodiments of the present invention, and it should be understood that the present invention is not limited by the example embodiments described herein.

In the description of the present invention, it should be noted that, for the azimuth words such as terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., the azimuth and positional relationships are based on the azimuth or positional relationships shown in the drawings, it is merely for convenience of describing the present invention and simplifying the description, and it is not to be construed as limiting the specific scope of protection of the present invention that the device or element referred to must have a specific azimuth configuration and operation.

It should be noted that the terms "first," "second," and the like in the description and in the claims of the present application are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.

The terms "comprises" and "comprising," along with any variations thereof, in the description and claims of the present application are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements that are expressly listed or inherent to such process, method, article, or apparatus.

In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; either directly or indirectly through intermediaries, or both elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

As shown in fig. 1, an image capturing module 10 according to an embodiment of the present application is illustrated, which includes a lens assembly 20, a photosensitive assembly 30, and a piezoelectric motor 40. In the embodiment of the present application, the piezoelectric motor 40 surrounds the outside of the lens assembly 20, the photosensitive assembly 30 is located below the lens assembly 20, and the lens assembly 20 is held on the photosensitive path of the photosensitive assembly 30. The lens assembly 20 is used for collecting imaging light from a photographed object and transmitting the imaging light to the photosensitive assembly 30, and the photosensitive assembly 30 is used for receiving the light passing through the lens assembly 20 to form a photographed image.

In the embodiment of the present application, referring to fig. 2, the lens assembly 20 includes a lens barrel 21 and one or more optical lenses 22 disposed therein. The lens assembly 20 is disposed above the photosensitive assembly 30, wherein at least one optical lens 22 is disposed inside the lens barrel 21, the lens barrel 21 surrounds the outer side of the optical lens 22, and the lens barrel plays a certain supporting role on the optical lens 22.

In this embodiment, with continued reference to fig. 2, the photosensitive assembly 30 includes at least one circuit board 31, at least one photosensitive chip 32 and a filter element 33, where the photosensitive chip 32 is a photosensitive portion of the photosensitive assembly 30 and is configured to receive imaging light from the outside and perform imaging, the photosensitive chip 32 is disposed at the bottom of the camera module 10, the photosensitive chip 32 is located above the circuit board 31, and the photosensitive chip 32 is mounted on and electrically connected to the circuit board 31. The filter element 33 is held on the photosensitive path of the photosensitive chip 32, so that the light entering the filter element 33 reaches the photosensitive chip 32 of the photosensitive assembly 30 after passing through the filter element 33, thereby realizing imaging.

The circuit board 31 may be used as a substrate of the photosensitive assembly 30, and is used to carry other parts of the photosensitive assembly 30. The circuit board 31 may have an inner surface 311 and an outer surface 312 opposite the inner surface 311, the inner surface 311 facing the object side, the outer surface 312 facing away from the object side. The wiring board 31 includes a wiring board main body, a connection tape, and a connector portion (wherein the connection tape and the connector portion are not shown in the drawing). The connection strap portion is connected between the circuit board main body and the connector portion to achieve electrical conduction between the circuit board main body and the connector portion, the connector being for connection with an external device.

The photo chip 32 may be a photo coupling element (CCD) or a complementary metal oxide semiconductor element (COMS), and the photo chip 32 may include a photo region at the center and a non-photo region surrounding the photo region. The photosensitive area of the photosensitive chip 32 can receive the light passing through the lens assembly 20 and has a photosensitive path corresponding to the photosensitive area. The photosensitive chip 32 may be disposed on the inner surface 311 of the circuit board 31. Specifically, the photosensitive chip 32 may be mounted on a central area of the inner surface 311 of the circuit board 31. The specific embodiment of the photosensitive chip 32 electrically connected to the circuit board 31 is not limited in this application. For example, the photosensitive Chip 32 may be electrically connected to the circuit board body of the circuit board 31 by wire bonding (wire bonding), soldering, flip-Chip (FC), rewiring layer (RDL, redistribution Layer), or the like. For example, the electrical connection may be implemented as wire bonding. After the photosensitive chip 32 is mounted on the circuit board 31, one end of the gold wire is connected to the photosensitive chip 32 by a gold wire bonding process, and the other end is connected to the circuit board 31. The connection lines may also be of other types, such as silver lines, copper lines, etc. In some embodiments, the circuit board 31 has a mounting groove that accommodates the photo-sensing chip 32, and the shape of the mounting groove corresponds to the shape of the photo-sensing chip 32. Illustratively, the depth of the mounting slot may be equal to the thickness of the circuit board 31. The filter element 33 is held on the photosensitive path of the photosensitive chip 32 for filtering the imaging light entering the photosensitive chip 32.

In some embodiments, the photosensitive assembly 30 further includes a support 34 for supporting and holding the filter element 33. The filter element 33 is mounted on the bracket 34 and corresponds to at least a portion of the photosensitive area of the photosensitive chip 32 to be held on the photosensitive path of the photosensitive chip 32. The manner of combining the bracket 34 and the circuit board 31 is not limited in this application. The bracket 34 may be formed separately to form a structure independent of the circuit board 31, and the bracket 34 of the filter element 33 may be attached to the circuit board 31 by an adhesive, and may be used to support other components. In other embodiments, the bracket 34 of the filter element 33 and the circuit board 31 are integrally formed at a predetermined position of the main body of the circuit board 31 through a molding process.

The photosensitive assembly 30 further includes at least one electronic component 35, and the electronic component 35 is disposed on the circuit board 31 and electrically connected to the circuit board 31. The electronic component 35 may be disposed on the inner surface 311 of the circuit board 31 and spaced from the photosensitive chip 32. Specifically, the electronic component 35 may be mounted on an edge region of the inner surface 311 of the circuit board 31 and spaced apart from the photosensitive chip 32 by a certain distance. The electronic components 35 may be implemented, for example, as capacitors, resistors, driving devices, etc.

In the embodiment of the present application, as shown in fig. 3 and 4, the piezoelectric motor 40 includes a fixed assembly 41, a movable carrier 42, a piezoelectric actuator 43, and a guide mechanism 44.

The fixing assembly 41 further comprises a base 411 and a housing 412. The base 411 is located at the bottom of the piezoelectric motor 40 for the lens assembly 20 to support, the base 411 has a through hole 4111, the through hole 4111 is a circular through hole with a larger or same outline compared with the lens assembly 20, the through hole 4111 of the base 411 does not affect the high transmittance of the lens assembly 20 to visible light, and the center line of the through hole 4111 is coaxial with the optical lens 22, so that the base 411 can surround the lens assembly 20.

The housing 412 is located above the base 411, the housing 412 has a hollow cavity 4121, the hollow cavity 4121 is a circular through hole 4111 with a larger or same profile as the lens assembly 20, and the hollow cavity 4121 of the housing 412 does not affect the high transmittance of the optical lens 22 to visible light. The bottom of the housing 412 is connected to the base 411, and the housing 412 encapsulates the piezoelectric actuator 43, the movable carrier 42, and other components, thereby protecting the components inside the camera module 10. Wherein the housing 412 further has at least one housing ball groove 4122 therein.

The movable carrier 42 is located above the base 411 for the lens assembly 20 to support, the movable carrier 42 has a receiving cavity 421, the receiving cavity 421 is a circular through hole 4111 with a larger or same profile as the lens assembly 20, and the receiving cavity 421 of the movable carrier 42 does not affect the high transmittance of the optical lens 22 to visible light, and the movable carrier 42 can surround the lens assembly 20. Wherein, the outer side wall of the movable carrier 42 further has at least one carrier ball groove 422, and the carrier ball groove 422 and the housing ball groove 4122 are positioned corresponding to each other.

Referring to fig. 3, 4 and 5, the piezoelectric actuator 43 includes a piezoelectric vibrator 431, a piezoelectric friction head 432, a piezoelectric friction plate 433 and a spring 434.

The piezoelectric vibrator 431 has a rectangular long shape, and the rectangular long side of the piezoelectric vibrator 431 is parallel to an outer side direction of the base 411 and perpendicular to the optical axis direction. The piezoelectric vibrator 431 is disposed outside the movable carrier 42, a surface of the piezoelectric vibrator 431 facing the lens assembly 20 is an inner surface 4311 of the piezoelectric vibrator 431, a surface of the piezoelectric vibrator 431 away from the lens assembly 20 is an outer surface 4312 of the piezoelectric vibrator 431, and the inner surface 4311 is disposed opposite to the outer surface 4312.

The inner side 4311 of the piezoelectric vibrator 431 is provided with a piezoelectric friction head 432, the piezoelectric friction head 432 is located at the center of the inner side 4311 of the piezoelectric vibrator 431, a piezoelectric friction plate 433 is arranged at the other side of the piezoelectric friction head 432, the piezoelectric friction plate 433 is fixed on the movable carrier 42, the piezoelectric friction plate 433 is of a rectangular sheet structure, the piezoelectric friction plate 433 and the inner side 4311 of the piezoelectric vibrator 431 are arranged in parallel, and the piezoelectric friction head 432 is abutted to the center of the piezoelectric friction plate 433, so that the stress of the piezoelectric friction head 432 and the piezoelectric friction plate 433 is more uniform. The piezoelectric friction head 432 is closely attached to the piezoelectric vibrator 431 and the piezoelectric friction plate 433, and is driven by generating friction force.

The outer side 4312 of the piezoelectric vibrator 431 is provided with a spring 434, and the spring 434 further includes a spring frame 4341, a spring extension arm 4342, and a spring positioning hole 4343.

The elastic piece 434 is a rectangular sheet structure, the elastic piece 434 is disposed parallel to the outer side 4312 of the piezoelectric vibrator 431, and the elastic piece 434 is perpendicular to the upper surface of the base 411. The rectangular long side of the elastic piece 434 is attached to the piezoelectric vibrator 431, the middle area of the elastic piece 434 is an elastic piece frame 4341, the elastic piece frame 4341 is in a rectangular hollow structure, the size of the elastic piece frame 4341 is larger than the area size of the outer side surface 4312 of the piezoelectric vibrator 431, and the hollow structure of the elastic piece frame 4341 can prevent the piezoelectric vibrator 431 from interfering.

The elastic sheet 434 has an elastic sheet extension arm 4342 on the upper and lower sides of the optical axis direction, preferably, the number of the elastic sheet extension arms 4342 is 2, the elastic sheet extension arm 4342 includes a first extension arm 43421 and a second extension arm 43422, the first extension arm 43421 is located near one end of the base 411, the first extension arm 43421 extends toward the base 411 in the optical axis direction, and extends to the first extension arm 43421 and the base 411 when being attached, and then bends and extends toward the outer side of the elastic sheet 434, and the bending angle is 90 °, the bending surface at this time is always attached to the upper surface of the base 411, and bends and extends in the optical axis direction after extending to a certain length, the bending angle is 90 ° and the extending direction is away from the base 411, and the bending surface at this time is always perpendicular to the upper surface of the base 411, so that the bending portion of the first extension arm 43421 can form a groove structure. The second extension arm 43422 is located at one end far away from the base 411, the second extension arm 43422 extends in the direction away from the base 411 along the optical axis, and extends to a certain length, and then bends and extends towards the outer side of the elastic sheet 434, and the bending angle is 90 °, and the bending surface is always parallel to the upper surface of the base 411. The bending part of the spring extension arm 4342 is embedded in the housing 412 and keeps a certain gap with the housing 412 in the optical axis direction, so as to adjust the positional relationship of the spring 434 relative to the base 411.

The connection between the elastic piece 434 and the piezoelectric vibrator 431 is provided with an elastic piece positioning hole 4343, the elastic piece positioning hole 4343 is in a through hole structure, and the elastic piece positioning hole 4343 is located at the center of the rectangular long side of the elastic piece 434, so that the piezoelectric vibrator 431 is also located at the center of the elastic piece 434, the elastic piece 434 is convenient to install, and the structure of the camera module 10 is more stable.

The elastic piece 434 can play a role in fixing and limiting the piezoelectric vibrator 431, and can provide a certain pre-pressure; the elastic sheet frame 4341 can prevent the interference of the piezoelectric vibrator 431 on the one hand, and the elastic sheet frame 4341 can prevent the deformation of the elastic sheet 434 to affect the pre-pressure of the elastic sheet 434 to the piezoelectric vibrator 431 on the other hand; the dome extension arm 4342 can provide a bearing force to the housing 412 and other components; the elastic piece 434 makes the piezoelectric vibrator 431 and the piezoelectric friction plate 433 contact with the movable carrier 42.

With continued reference to fig. 3, 4 and 5, the fixing assembly 41 further includes an FPC flexible board 413 and at least one fixing member 414. The FPC flexible board 413 is attached to the outer side of the elastic piece 434, and the FPC flexible board 413 is located at a groove of the first extension arm 43421 of the elastic piece 434, one end of the FPC flexible board 413 is connected to the elastic piece 434, the other end of the FPC flexible board 413 extends out and bends along another direction of the elastic piece 434, and extends along a parallel direction of another outer side edge of the base 411, and the FPC flexible board 413 is perpendicular to the base 411. The first fixing member 4141 is attached to the outer side of the FPC flexible board 413, and the length and width of the first fixing member 4141 are both greater than those of the FPC flexible board 413, so that the FPC flexible board 413 can be completely attached to the first fixing member 4141, the first fixing member 4141 can play a certain supporting role, and the first fixing member 4141 is also perpendicular to the base 411. A position sensor (not shown) is disposed on the inner sides of the first fixing member 4141 and the FPC flexible board 413, the position sensor is parallel to the optical axis direction, and the position sensor is disposed on one side of the piezoelectric vibrator 431, and the position sensor can be used for sensing the position of the movable carrier 42. The other side of the unbent end of the FPC flexible board 413 is provided with a second fixing member 4142, the size of the second fixing member 4142 is the same as the size of the first fixing member 4141, the second fixing member 4142 is parallel to the direction of the other outer side of the base 411, and the second fixing member 4142 is also perpendicular to the base 411. The first fixing members 4141 and the second fixing members 4142 are symmetrically distributed with the piezoelectric vibrator 431 as a center, so that the overall structure is more stable.

As shown in fig. 4, in some embodiments, the guiding mechanism 44 includes at least one ball 441, the ball 441 is disposed on an outer side wall of the movable carrier 42, the movable carrier 42 has at least one carrier ball groove 422 capable of being accommodated in the ball 441, wherein one end of the ball 441 is disposed in the carrier ball groove 422 of the movable carrier 42, and the other end of the ball 441 is disposed in the housing ball groove 4122 of the housing 412, such that the ball 441 can be covered by the carrier ball groove 422 of the movable carrier 42 and the housing ball groove 4122 of the housing 412. The balls 441 are vertically disposed in the optical axis direction, and at least one ball 441 is disposed on the opposite side. The ball 441 can realize a plurality of degrees of freedom of movement, and in the case where the carrier ball groove 422 has a direction, the movement locus of the ball 441 is limited to the carrier ball groove 422, and thus can play a guiding role in the course of movement of the lens assembly 20. Preferably, the number of the carrier ball grooves 422 is two, and the two carrier ball grooves 422 are respectively disposed on two opposite sides of the movable carrier 42, so that the camera module 10 can keep stable, and the number of the balls 441 is six, wherein each carrier ball groove 422 is provided with three balls 441 inside, and the three balls 441 are stacked in a vertical direction (parallel to the optical axis direction), and it should be noted that the sizes of the balls 441 on the upper and lower sides, which are attached to the carrier ball grooves 422, are slightly larger than the sizes of the balls 441 located at the middle position, so as to reduce the contact points between the middle balls 441 and the carrier ball grooves 422, and play a role in preventing interference. Meanwhile, by providing the balls 441, friction force during movement can be reduced by the aid of the balls 441, and the balls 441 are disposed opposite to each other, so that the camera module 10 can be kept stable. The balls 441 are symmetrically arranged with the piezoelectric friction head 432 as a center, and because the piezoelectric vibrator 431 stretches and contracts in a movement stroke, the piezoelectric friction head 432 can tilt in an elliptical direction in the stretching and contracting process of the piezoelectric vibrator 431, so that the piezoelectric friction head 432 generates a tilting moment applied to the outer side wall of the movable carrier 42 in a movement track, and the balls 441 can disperse the tilting moment, so that the overall structure is more stable. The balls 441 replace sliding friction by rolling friction, and the balls 441, the carrier ball grooves 422 and the housing ball grooves 4122 serve as guide mechanisms 44 to provide a larger supporting force for the camera module 10, so that the parallelism between the piezoelectric vibrator and the movable carrier is further maintained.

Taking the piezoelectric actuator 43 as an example, the piezoelectric vibrator 431 is a substrate having an inverse piezoelectric effect, which is to apply an electric field in a polarization direction of a dielectric that is mechanically deformed when a potential difference is generated, and contracts or expands according to the polarization direction and the electric field direction, and can be used by polarizing the substrate in a thickness direction of a single crystal, a polycrystalline ceramic, a polymer, or the like. The piezoelectric vibrator 431 has an ultrasonic vibration function, and can realize elliptical motion on a specific electrode layer. The piezoelectric vibrator 431 is made of PZT material and is connected to the wiring board 31 to perform circuit conduction, thereby providing power supply excitation.

The inner surface 4311 and the outer surface 4312 of the piezoelectric vibrator 431 are parallel to the optical axis direction, each surface has two rectangular long sides and two rectangular short sides, the two perpendicular surfaces connected to the rectangular short sides of the inner surface 4311 and the outer surface 4312 of the piezoelectric vibrator 431 are the first end surface 4313 and the second end surface 4314 of the piezoelectric vibrator 431, the first end surface 4313 and the second end surface 4314 of the piezoelectric vibrator 431 are parallel to the optical axis direction, and each surface has four rectangular short sides. The surface close to the bending end of the FPC flexible board 413 is a first end surface 4313 of the piezoelectric vibrator 431, and the surface far away from the bending end of the FPC flexible board 413 is a second end surface 4314 of the piezoelectric vibrator 431.

Referring to fig. 6, the rectangular long side of the piezoelectric vibrator 431 is set to the X-axis direction, the rectangular short side of the piezoelectric vibrator 431 is set to the Y-axis direction, and the Z-axis direction is parallel to the optical axis direction and perpendicular to the X, Y axis direction. The Y-Z plane of the piezoelectric vibrator 431 is divided into four regions, wherein the upper left portion is a first region 43131, the upper right portion is a second region 43132, the lower right portion is a third region 43133, and the lower left portion is a fourth region 43134. Due to the piezoelectric effect of d31, every two areas are grouped in pairs to perform telescopic motion in the X-axis direction. Vibration in the Z-axis direction can be achieved when the first region 43131 and the second region 43132 are a set, and the third region 43133 and the fourth region 43134 are a set of motions; vibration in the Y-axis direction can be achieved when the first region 43131 and the fourth region 43134 are a set, and the second region 43132 and the third region 43133 are a set of motions. Assuming that the electrode polarization of the first region 43131 and the second region 43132 is +, the electrode polarization of the third region 43133 and the fourth region 43134 is-; the sin signal is input to the electrodes of the first region 43131 and the third region 43133, and the cos signal is input to the electrodes of the second region 43132 and the fourth region 43134; therefore, from a waveform perspective, the piezoelectric vibrator 431 moves in the state of sin in the first area 43131, cos in the second area 43132, cos in the third area 43133, cos in the third area 43134, and cos, so that the cyclic elongation of the second area 43132, the first area 43131, the fourth area 43134, the third area 43133, and the second area 43132 … … occurs, further, the periodic bending of the piezoelectric vibrator 431 is realized, and the elliptical motion is realized by the friction head at the surface of the piezoelectric vibrator 431, that is, the superposition of the Y-axis vibration and the Z-axis vibration forms the elliptical motion. In view of the Y-Z plane of piezoelectric vibrator 431, in the conventional piezoelectric technology, the height of piezoelectric vibrator 431 in the Z axis direction tends to be long, so as to ensure that piezoelectric vibrator 431 has a sufficiently long stroke.

In this embodiment, in order to make the electrode wiring of the piezoelectric vibrator 431 more reasonable, the first end surface 4313 of the piezoelectric vibrator 431 is taken as a front view, and referring to fig. 6, the piezoelectric vibrator 431 is divided into four areas in a transverse direction and a longitudinal direction, wherein the upper left portion is a first area 43131, the upper right portion is a second area 43132, the lower right portion is a third area 43133, and the lower left portion is a fourth area 43134. Assuming that two wires are led out from each region, i.e., each region has an electrode at the upper and lower ends, the first region 43131, the second region 43132, the third region 43133, and the fourth region 43134 each have electrodes at the upper and lower ends, for a total of 8 electrodes. Among the four regions, the lower electrodes of the first region 43131 and the second region 43132 and the upper electrodes (4 electrodes in total) of the third region 43133 and the fourth region 43134 are combined into a common ground. When polarization, the wiring condition of the signal is: the common ground electrode is grounded, the upper electrode of the first region 43131 and the upper electrode of the second region 43132 are connected to the positive electrode, and the lower electrode of the third region 43133 and the lower electrode of the fourth region 43134 are connected to the negative electrode; in driving, the common ground electrode is grounded, the upper electrode of the first region 43131 and the lower electrode of the third region 43133 input sin signals, and the upper electrode of the second region 43132 and the lower electrode of the fourth region 43134 input cos signals. The driving conditions according to the electrode connection mode are as follows: assuming that the polarization of the upper electrode of the first region 43131 is +, the upper electrode of the second region 43132 is also +, and the lower electrode of the third region 43133 and the lower electrode of the fourth region 43134 are-; considering the polarized operation of the electrodes in each region, as shown in fig. 7, the motion signal of the piezoelectric vibrator 431, i.e., the upper electrode in the first region 43131, is sin, the upper electrode in the second region 43132 is cos, the lower electrode in the third region 43133 is-sin, and the lower electrode in the fourth region 43134 is-cos.

In this embodiment, the first region 43131 and the third region 43133 of the piezoelectric vibrator 431 are grouped, the second region 43132 and the fourth region 43134 are grouped, the upper electrode of the first region 43131 of the piezoelectric vibrator 431 is connected to the lower electrode of the third region 43133, and the upper electrode of the second region 43132 of the piezoelectric vibrator 431 is connected to the lower electrode of the fourth region 43134, i.e. the electrodes of the two regions that are diagonal to each other are connected; with continued reference to fig. 7, since the motion signal of the piezoelectric vibrator 431, that is, the upper electrode of the first region 43131 is sin, the upper electrode of the second region 43132 is cos, the lower electrode of the third region 43133 is cos, and the lower electrode of the fourth region 43134 is cos, a phase difference of 180 ° is provided between the first region 43131 and the third region 43133, and a phase difference of 180 ° is provided between the second region 43132 and the fourth region 43134, so that the stroke of the piezoelectric vibrator 431 is longer when driving, and the height of the piezoelectric vibrator 431 is further shortened when seen from the direction of the first end surface 4313 of the piezoelectric vibrator 431, which conforms to the miniaturized design of the image capturing module 10.

After the piezoelectric actuator 43 is powered, the piezoelectric vibrator 431 performs a standing wave or a traveling wave on the Y-axis or the Z-axis, so as to drive the piezoelectric friction head 432 to generate an elliptical motion, and the piezoelectric friction head 432 and the piezoelectric friction plate 433 are in friction contact, so that the piezoelectric friction plate 433 moves, and the movable carrier 42 is driven to move. Specifically, when the piezoelectric actuator 43 is excited by the power supply, the piezoelectric vibrator 431 generates a telescopic motion form along the Y-axis direction and a stretching motion form along the optical axis direction (Z-axis), and the piezoelectric friction head 432 is driven by the piezoelectric vibrator 431 to perform an elliptical motion on the Y-Z-axis plane, so as to drive the piezoelectric friction plate 433 to move up and down in the Z-axis direction. The four areas of the piezoelectric vibrator 431 realize alternate vibration, namely, the four areas are protruded in sequence, the phase difference of each area is respectively 90 degrees, the electrode connection of the diagonal areas of the piezoelectric vibrator 431 is realized under the condition that waves have a certain length, the phase difference of the diagonal areas is 180 degrees, namely, the shape of 'upside down', and the connection mode ensures that the piezoelectric vibrator 431 has the advantages of large stroke, large thrust, high frequency, small size and the like.

Therefore, the piezoelectric actuator 43 has a degree of freedom in the Z-axis direction, and is capable of driving the movable carrier 42 to move in the Z-axis direction to adjust the relative positional relationship between the lens assembly 20 and the photosensitive assembly 30, thereby realizing AF zooming. The movable carrier 42 also plays a certain supporting role, so that the stability of the movement of the piezoelectric actuator 43 in the optical zooming process can be improved, and the imaging quality can be improved.

When the piezoelectric vibrator 431 moves after being electrified, the piezoelectric vibrator 431 has a certain amplitude in the stroke excited by a power supply, wherein the amplitude of the middle part of the main body of the piezoelectric vibrator 431 is larger, and the amplitude of the two side parts of the main body of the piezoelectric vibrator 431 is smaller, so that the elastic sheet frame 4341 can prevent the interference of the piezoelectric vibrator 431; and the piezoelectric vibrator 431 can also deform to a certain extent after being electrified, and the elastic sheet 434 can provide potential energy in a certain direction, so that the elastic sheet 434 and the piezoelectric vibrator 431 are pressed tightly, the deformation degree of the piezoelectric vibrator 431 is reduced, the piezoelectric vibrator 431 can still return to the original position after vibrating, and next vibration is implemented.

In view of the electrode level, as shown in fig. 8 and 9, the four regions of the piezoelectric vibrator 431 may be further divided into a first phase electrode 43135, a second phase electrode 43136, a third phase electrode 43137 and a fourth phase electrode 43138. The first region 43131 of the piezoelectric vibrator 431 has a first phase electrode 43135 and a second phase electrode 43136, the second region 43132 of the piezoelectric vibrator 431 has a second phase electrode 43136 and a third phase electrode 43137, the third region 43133 of the piezoelectric vibrator 431 has a first phase electrode 43135 and a fourth phase electrode 43138, and the fourth region 43134 of the piezoelectric vibrator 431 has a third phase electrode 43137 and a fourth phase electrode 43138. It should be noted that the first phase electrode 43135, the second phase electrode 43136, the third phase electrode 43137 and the fourth phase electrode 43138 are stacked on each other in a rectangular long side direction, wherein the second phase electrode 43136 is connected to the first region 43131 and the second region 43132 of the piezoelectric vibrator 431, and the second phase electrode 43136 is a common-potential electrode disposed in a rectangular long side direction; the fourth phase electrode 43138 is connected to the third region 43133 and the fourth region 43134 of the piezoelectric vibrator 431, and the fourth phase electrode 43138 is a common-potential electrode disposed in a rectangular long-side direction, so that the number of stacked electrode layers can be reduced, and the electrode size can be further reduced. In addition, the piezoelectric vibrator 431 further has at least one substrate 4315, the substrate 4315 is disposed on the inner side 4311 and the outer side 4312 of the piezoelectric vibrator 431 in a rectangular short side direction, so as to be in communication with the whole electrode layer of the piezoelectric vibrator 431, and the substrate 4315 is disposed on the side surface of the piezoelectric vibrator 431, so that the electrode size can be further reduced, and the space can be reasonably utilized. The substrate 4315 further includes a first substrate 43151 and a second substrate 43152, the first substrate 43151 is connected to the first phase electrode 43135 of the first region 43131 and the first phase electrode 43135 of the third region 43133, and the second substrate 43152 is connected to the third phase electrode 43137 of the second region 43132 and the third phase electrode 43137 of the fourth region 43134, so as to ensure that the electrodes of the two regions of the piezoelectric vibrator 431, which are diagonal to each other, are mutually communicated, thereby reducing the size of the piezoelectric vibrator 431 and ensuring that the piezoelectric vibrator 431 has a large stroke.

In addition, the piezoelectric vibrator 431 is fixed by using the elastic piece positioning hole 4343 of the elastic piece 434, where the elastic piece positioning hole 4343 is disposed in the middle section area of the outer side surface 4312 of the piezoelectric vibrator 431, when the two resonant frequencies of the piezoelectric vibrator 431 in the Y axis and the Z axis directions are almost the same, and the motion track of the piezoelectric friction head 432 is elliptical, so as to drive the movable carrier 42 to perform the motion in the Z axis direction, thereby realizing AF zoom.

The foregoing has outlined the basic principles, features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made therein without departing from the spirit and scope of the invention, which is defined by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (10)

1. A piezoelectric motor, comprising:

the fixing assembly comprises a base and a shell, wherein the shell is positioned above the base;

a movable carrier disposed above the base;

the piezoelectric actuator comprises a piezoelectric vibrator and a spring plate, wherein one surface of the spring plate is arranged on one surface of the piezoelectric vibrator, and the other surface of the spring plate is connected with the shell; the elastic sheet is abutted against the piezoelectric vibrator, and the elastic sheet is contacted with two rectangular short sides of the piezoelectric vibrator; the rectangular long side of the elastic piece is perpendicular to the rectangular long side of the piezoelectric vibrator.

And a guide mechanism that maintains parallelism of the piezoelectric vibrator and the movable carrier.

2. The piezoelectric motor of claim 1, wherein the piezoelectric actuator further comprises:

the piezoelectric friction head is arranged at the center of one surface of the piezoelectric vibrator.

3. The piezoelectric motor of claim 2, wherein the piezoelectric actuator further comprises: and the piezoelectric friction plate is abutted with the piezoelectric friction head.

4. The piezoelectric motor according to claim 3, wherein the piezoelectric friction plate is disposed in parallel with one surface of the piezoelectric vibrator, and the piezoelectric friction head is located at a center position of the piezoelectric friction plate.

5. The piezoelectric motor according to claim 1, wherein the spring plate has a spring plate frame, a middle area of the spring plate frame is a rectangular hollow structure, and a size of the spring plate frame is larger than an area size of the surface of the piezoelectric vibrator.

6. The piezoelectric motor according to claim 5, wherein the spring frame of the spring provides a pre-compression force on at least two rectangular short sides of the piezoelectric vibrator.

7. The piezoelectric motor according to claim 1, wherein a pre-pressing edge of the elastic sheet attached to the piezoelectric vibrator is parallel to a driving direction of the piezoelectric vibrator.

8. The piezoelectric motor according to claim 1, wherein the spring further comprises at least one spring extension arm having a groove structure, the spring extension arm being embedded in the housing with a gap therebetween.

9. The piezoelectric motor according to claim 1, wherein the elastic piece further has at least one elastic piece positioning hole through which the elastic piece is fixed to the piezoelectric vibrator, the elastic piece positioning hole being located at a position where an amplitude of the piezoelectric vibrator in a rectangular long side direction is minimum.

10. The piezoelectric motor according to claim 8, wherein the fixing component further comprises an FPC flexible board, the FPC flexible board is disposed on the groove structure of the spring plate extension arm, and the FPC flexible board is attached to the spring plate.