WO2024037631A1

WO2024037631A1 - Piezoelectric motor and camera module comprising same

Info

Publication number: WO2024037631A1
Application number: PCT/CN2023/113797
Authority: WO
Inventors: 傅强; 唐磊; 赵波杰
Original assignee: 宁波舜宇光电信息有限公司
Priority date: 2022-08-19
Filing date: 2023-08-18
Publication date: 2024-02-22

Abstract

The present application provides a piezoelectric motor, comprising a fixed assembly, a movable carrier, a piezoelectric actuator and a guide mechanism. The fixed assembly comprises a base and a housing, etc. The movable carrier is arranged above the base. The guide mechanism maintains the parallelism of a piezoelectric vibrator and the movable carrier. The piezoelectric actuator comprises the piezoelectric vibrator and an elastic sheet, etc., wherein one face of the elastic sheet is arranged on one surface of the piezoelectric vibrator, and the other face of the elastic sheet is connected to the housing. The elastic sheet abuts against the piezoelectric vibrator, the elastic sheet makes contact with two short rectangle sides of the piezoelectric vibrator, and long rectangle sides of the elastic sheet are perpendicular to long rectangle sides of the piezoelectric vibrator.

Description

Piezoelectric motor and its camera module

Technical field

This solution belongs to the technical field of camera modules, and particularly relates to a camera module with a piezoelectric motor structure.

Background technique

Currently, camera modules in mobile phone terminals generally include: optical components, actuators, filter components and image sensors. Optical components often include optical lenses, optical barrels, etc. Generally in camera modules, when the sensor detects movement, the actuator works to cause the optical element to perform translational movement, thereby compensating the imaging beam, that is, the displacement (linear displacement and/or angular displacement) caused by the movement. Make compensation. In order to meet the development trend of thinner and lighter portable electronic devices, the industry is trying to apply actuators, which are widely used in medical, industrial, microscope, camera and other fields, to small-sized camera modules. However, due to their configuration in portable electronic devices, Compared with the small-sized camera module of the device, the existing actuator has a complex structure and a larger volume. As a result, it is still difficult to apply the existing actuator to a small-sized camera module that can be mass-produced. Bigger challenge.

In recent years, with the rapid development and improvement of various functions of portable electronic devices, camera modules, which are one of the important components of portable electronic devices, have also made great progress in design and application. Users have increasingly higher requirements for the size of camera modules. Users expect camera modules with high pixels, small size, and both zoom and anti-shake capabilities. But generally speaking, camera modules with higher pixels will have more optical components, and the total track length (TTL) of the optical components will be larger. Larger optical components require matching The load-bearing capacity of the motor must also increase, and the size of the motor is also increasing. There is a voice coil-type shrapnel motor in the prior art, but due to the problem of the load-bearing capacity of the shrapnel, the shrapnel cannot well hold large-volume and heavy-weight optical components. There are also ball motors in the prior art. However, due to the complex structure of the ball motor and the lack of mechanical reset components, it is easy to cause abnormal noise and the like. Therefore, using piezoelectric motors in the field of camera modules can solve most problems. However, since the piezoelectric motor is a contact actuator solution, the piezoelectric motor and the driven part need to be frictionally connected to each other before the piezoelectric motor can be driven. The driven part moves and the contact design requires special attention to the yield during the assembly process, reliability during use, product performance, and size miniaturization. Therefore, the piezoelectric motor solution needs to be designed to achieve more precision. performance.

In response to the above problems, the present invention provides a piezoelectric motor camera module. By using a piezoelectric actuator, a high-precision zoom effect is achieved, and the size of the overall motor is prevented from further increasing, which reduces the cost of the camera module. group size, mention The reliability of the piezoelectric motor is improved, and the installation yield of the piezoelectric motor is optimized through structural improvements, so at least one of the above problems can be solved.

Contents of the invention

Further objects and advantages of the present invention will be fully realized through an understanding of the following description and drawings.

An object of the present invention is to provide a piezoelectric motor that overcomes the deficiencies of the prior art and designs the piezoelectric motor to achieve at least one of the effects of easy assembly, compact size, and excellent mechanical reliability.

According to one aspect of the present invention, the present invention provides a piezoelectric motor, which includes:

A fixing component, the fixing component includes a base and a shell, wherein the shell is located above the base;

Movable carrier, the movable carrier is arranged above the base;

Piezoelectric actuator, the piezoelectric actuator includes a piezoelectric vibrator and a spring piece, wherein one side of the spring piece is disposed on a surface of the piezoelectric vibrator, and the other side of the spring piece is connected to the housing; The elastic piece is in contact with the piezoelectric oscillator, and the elastic piece is in contact with the two rectangular short sides of the piezoelectric oscillator; wherein, the rectangular long side of the elastic piece is opposite to the rectangular long side of the piezoelectric oscillator. vertical.

A guide mechanism maintains the parallelism of the piezoelectric vibrator and the movable carrier.

According to an embodiment of the present invention, the piezoelectric actuator further includes: a piezoelectric friction head, the piezoelectric friction head is disposed at a center position of a surface of the piezoelectric vibrator.

According to an embodiment of the present invention, the piezoelectric actuator further includes: a piezoelectric friction plate, the piezoelectric friction plate is in contact with the piezoelectric friction head.

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

According to an embodiment of the present invention, the elastic piece has an elastic piece frame, the middle area of the elastic piece frame is a rectangular hollow structure, and the size of the elastic piece frame is larger than the area size of the surface of the piezoelectric vibrator.

According to an embodiment of the present invention, the elastic frame of the elastic piece provides pre-pressure on at least two rectangular short sides of the piezoelectric vibrator.

According to an embodiment of the present invention, the pre-compression edge of the elastic piece and the piezoelectric vibrator is parallel to the driving direction of the piezoelectric vibrator.

According to an embodiment of the present invention, the elastic piece further includes at least one elastic piece extending arm, the elastic piece extending arm has a groove structure, the elastic piece extending arm is embedded in the housing and leaves a certain gap with the housing. .

According to an embodiment of the present invention, 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 is located on the piezoelectric vibrator. The amplitude of the oscillator in the long side direction of the rectangle is the smallest.

According to an embodiment of the present invention, the fixing component further includes an FPC soft plate, the FPC soft plate is arranged in the groove structure of the elastic piece extending arm, and the FPC soft plate is attached to the elastic piece.

According to another aspect of the present invention, the present invention provides a piezoelectric actuator, which includes:

A piezoelectric vibrator, the piezoelectric vibrator has an electrode, and the piezoelectric vibrator is a cuboid;

A piezoelectric friction head, the piezoelectric friction head is disposed on a surface of the piezoelectric vibrator;

A piezoelectric friction plate, the piezoelectric friction plate is in contact with the piezoelectric friction head;

An elastic piece, the elastic piece is arranged on the other surface of the piezoelectric vibrator;

Wherein, the plane formed by the rectangular short side of the piezoelectric oscillator is divided into four regions, and the diagonal regions are connected by electrodes.

According to an embodiment of the present invention, the four regions of the piezoelectric oscillator are a first region, a second region, a third region and a fourth region in order in a clockwise direction.

According to an embodiment of the present invention, each of the four regions of the piezoelectric vibrator has electrodes at upper and lower ends.

According to an embodiment of the present invention, the upper end electrode of the first region of the piezoelectric oscillator is connected to the lower end electrode of the third region, and the upper end electrode of the second region of the piezoelectric oscillator is connected to the lower end of the fourth region. The electrodes are connected to each other The electrodes in the two diagonal areas are connected.

According to an embodiment of the present invention, the elastic piece also has at least one elastic piece positioning hole, and the elastic piece is fixed to the piezoelectric oscillator through the elastic piece positioning hole. The rectangular long side direction of the piezoelectric oscillator is The same resonant frequency as the short side of the rectangle.

According to an embodiment of the present invention, the piezoelectric vibrator further includes a first phase electrode, a second phase electrode, a third phase electrode and a fourth phase electrode. Wherein, the first region of the piezoelectric oscillator has a first phase electrode and a second phase electrode, the second region of the piezoelectric oscillator has a second phase electrode and a third phase electrode, and the third region of the piezoelectric oscillator has a first phase electrode and a second phase electrode. A region has a first phase electrode and a fourth phase electrode, and a fourth region of the piezoelectric vibrator has a third phase electrode and a fourth phase electrode.

According to an embodiment of the present invention, the first phase electrode, the second phase electrode, the third phase electrode and the fourth phase electrode of the piezoelectric vibrator are stacked on each other in a rectangular long side direction.

According to an embodiment of the present invention, the second phase electrode of the piezoelectric oscillator is connected to the first region and the second region of the piezoelectric oscillator with a common potential electrode, and the fourth phase electrode of the piezoelectric oscillator A common potential electrode is connected to the third region and the fourth region of the piezoelectric vibrator.

According to an embodiment of the present invention, the piezoelectric oscillator further has at least one substrate, the substrate is disposed on a surface of the piezoelectric oscillator in a rectangular short side direction, and the substrate communicates with the piezoelectric oscillator. electrode layer.

According to an embodiment of the present invention, the substrate includes a first substrate and a second substrate, and the first substrate is connected to the first phase electrode and the third phase electrode in the first region of the piezoelectric oscillator. The second substrate is connected to the third phase electrode in the second area and the third phase electrode in the fourth area of the piezoelectric vibrator.

These and other objects, features and advantages of the present invention are fully demonstrated by the following detailed description, drawings and claims.

Description of drawings

Figure 1 shows a schematic diagram of the overall structure of the camera module in this application.

Figure 2 shows a schematic cross-sectional view of the camera module in this application.

Figure 3 shows a schematic cross-sectional view of the piezoelectric motor in this application.

Figure 4 shows an exploded schematic diagram of the piezoelectric motor in this application.

Figure 5 shows an exploded schematic diagram of the piezoelectric motor in this application from another angle.

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

Figure 7 shows a schematic diagram of the electrical signal waveform of the medium-voltage electric vibrator in this application.

Figure 8 shows a schematic diagram of the electrode structure of the piezoelectric vibrator in this application.

Figure 9 shows a schematic side structural view of the piezoelectric vibrator in this application.

The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of the embodiments of the present invention in conjunction with the accompanying drawings. The drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the description. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. In the drawings, like reference numbers generally represent like components or steps.

Detailed ways

Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments of the present invention. It should be understood that the present invention is not limited to the example embodiments described here.

In the description of the present invention, it should be noted that for directional words, such as the terms "center", "transverse", "longitudinal", "length", "width", "thickness", "upper", "lower" , "Front", "Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inside", "Outside", "Clockwise", "Counterclockwise" ", etc. indicate the orientation and positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation or be in a specific orientation. The construction and operation should not be construed as limiting the specific protection scope of the present invention.

It should be noted that the terms "first", "second", etc. in the description and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

The terms "comprising" and "having" and any variations thereof in the description and claims of this application are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or product that includes a series of steps or units. equipment It is not necessary to be limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to the process, method, product or apparatus.

In the description of the present invention, it should also be noted that, unless otherwise clearly stated and limited, the terms "set", "installation", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, It can also be a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, a contact connection or an indirect connection through an intermediate medium; it can be an internal connection between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

As shown in FIG. 1 , a camera 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 assembly 20 . 30 on the photosensitive path. The lens assembly 20 is used to collect imaging light from the photographed object and transmit the imaging light to the photosensitive assembly 30. The photosensitive assembly 30 is used to receive the light passing through the lens assembly 20 to form the photographed image. 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 arranged inside the lens barrel 21 , and the lens barrel 21 surrounds the outside of the optical lens 22 . The barrel plays a certain supporting role for the optical lens 22 .

In the embodiment of the present application, continuing to refer to FIG. 2 , the photosensitive component 30 includes at least one circuit board 31 , at least one photosensitive chip 32 and a filter element 33 . The photosensitive chip 32 is the photosensitive part of the photosensitive component 30 , used to receive imaging light from the outside and perform imaging, wherein 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 disposed at the bottom of the camera module 10. The 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 component 30 after passing through the filter element 33 , thereby achieving imaging.

The circuit board 31 can be used as a substrate of the photosensitive component 30 to carry other parts of the photosensitive component 30 . The circuit board 31 may have an inner surface 311 and an outer surface 312 opposite to the inner surface 311. The inner surface 311 faces the object. side, the outer surface 312 faces away from the object side. The circuit board 31 includes a circuit board body, a connecting strap and a connector part (the connecting strap and the connector part are not shown in the figure). The connecting strap part is connected between the circuit board main body and the connector part to achieve electrical conduction between the circuit board main body and the connector part, and the connector is used to connect with external equipment. .

The photosensitive chip 32 may be a photosensitive coupling device (CCD) or a complementary metal oxide semiconductor device (COMS), and the photosensitive chip 32 may include a central photosensitive area and a non-photosensitive area surrounding the photosensitive area. The photosensitive area of the photosensitive chip 32 can receive light passing through the lens assembly 20 and has a photosensitive path corresponding to the photosensitive area. The photosensitive chip 32 can be disposed on the inner surface 311 of the circuit board 31 . Specifically, the photosensitive chip 32 can be mounted on the central area of the inner surface 311 of the circuit board 31 . The specific implementation manner in which the photosensitive chip 32 is electrically connected to the circuit board 31 is not limited by this application. For example, the photosensitive chip 32 can be electrically connected to the circuit board 31 through wire bonding (gold wire), welding, flip-chip (FC), redistribution layer (RDL), etc. The main body of the circuit board. By way of 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 and the other end is connected to the circuit board 31 through a gold wire process. The connecting wire can also be of other types, such as silver wire, copper wire, etc. In some embodiments, the circuit board 31 has a mounting groove for accommodating the photosensitive chip 32 , and the shape of the mounting groove corresponds to the shape of the photosensitive chip 32 . For example, the depth of the installation groove 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 and is used to filter the imaging light entering the photosensitive chip 32 .

In some embodiments, the photosensitive component 30 further includes a bracket 34 for supporting and retaining the filter element 33 . The filter element 33 is installed on the bracket 34 and corresponds to at least part of the photosensitive area of the photosensitive chip 32 so as to be held on the photosensitive path of the photosensitive chip 32 . The combination method of the bracket 34 and the circuit board 31 is not limited by this application. The bracket 34 can be molded separately to form a structure independent of the circuit board 31. The bracket 34 of the filter element 33 is attached to the circuit board 31 through adhesive and can 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 preset position on the main body of the circuit board 31 through a molding process.

The photosensitive component 30 further includes at least one electronic component 35 . The electronic component 35 is disposed on the circuit board 31 and is electrically connected to the circuit board 31 . The electronic component 35 can be disposed on the inner surface 311 of the circuit board 31, and is spaced apart from the photosensitive chip 32 . Specifically, the electronic component 35 can be mounted on the edge area of the inner surface 311 of the circuit board 31 and be separated from the photosensitive chip 32 by a certain distance. The electronic component 35 may be implemented as a capacitor, a resistor, a driving device, etc., for example.

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

The fixing component 41 further includes a base 411 and a housing 412 . The base 411 is located at the bottom of the piezoelectric motor 40 and can be supported by the lens assembly 20 . The base 411 has a through hole 4111 , and the through hole 4111 has a contour similar to that of the lens assembly 20 A larger or the same circular through hole, and the through hole 4111 of the base 411 does not affect the high transmittance of the lens assembly 20 for visible light, and the center line of the through hole 4111 is on the same optical axis as 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 the same outline as that of 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. The housing 412 covers the piezoelectric actuator 43, the movable carrier 42 and other other components inside, thereby protecting the internal components of the camera module 10. device protection. The housing 412 also has at least one housing ball groove 4122 inside.

The movable carrier 42 is located above the base 411 and can be supported by the lens assembly 20. The movable carrier 42 has a receiving cavity 421, and the receiving cavity 421 has a contour similar to that of the lens assembly. 20 or the same circular through hole 4111, and the accommodation cavity 421 of the movable carrier 42 does not affect the high transmittance of the optical lens 22 to visible light, the movable carrier 42 can surround all The lens assembly 20 is described. The outer wall of the movable carrier 42 also has at least one carrier ball groove 422, and the positions of the carrier ball groove 422 and the housing ball groove 4122 correspond to each other.

Referring to FIGS. 3 , 4 and 5 , the piezoelectric actuator 43 includes a piezoelectric vibrator 431 , a piezoelectric friction head 432 , a piezoelectric friction piece 433 and an elastic piece 434 .

The piezoelectric vibrator 431 is in the shape of a rectangular strip. The long side of the rectangle of the piezoelectric vibrator 431 is parallel to an outer side of the base 411 and perpendicular to the optical axis direction. The piezoelectric vibrator 431 is disposed outside the movable carrier 42, and the The side of the piezoelectric vibrator 431 facing the lens assembly 20 is the inner side 4311 of the piezoelectric vibrator 431, and the side of the piezoelectric vibrator 431 away from the lens assembly 20 is the outer side 4312 of the piezoelectric vibrator 431. And its inner side 4311 and outer side 4312 are arranged oppositely.

A piezoelectric friction head 432 is provided on the inner side 4311 of the piezoelectric vibrator 431. The piezoelectric friction head 432 is located at the center of the inner side 4311 of the piezoelectric vibrator 431. The other side of the piezoelectric friction head 432 A piezoelectric friction plate 433 is provided on the side. The piezoelectric friction plate 433 is fixed to the movable carrier 42. The piezoelectric friction plate 433 is a rectangular sheet structure, and the piezoelectric friction plate 433 is connected to the movable carrier 42. The inner surface 4311 of the piezoelectric vibrator 431 is arranged in parallel, and the piezoelectric friction head 432 abuts the center position of the piezoelectric friction plate 433 so that the piezoelectric friction head 432 and the piezoelectric friction plate 433 are in contact with each other. The force is more uniform. The piezoelectric friction head 432 is in close contact with the piezoelectric vibrator 431 and the piezoelectric friction plate 433 to generate frictional force for driving.

An elastic piece 434 is provided on the outer surface 4312 of the piezoelectric vibrator 431 . The elastic piece 434 further includes an elastic piece frame 4341 , an elastic piece extending arm 4342 and an elastic piece positioning hole 4343 .

The elastic piece 434 is a rectangular sheet structure, the elastic piece 434 is arranged parallel to the outer surface 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 fits the piezoelectric vibrator 431. The middle area of the elastic piece 434 is an elastic frame 4341. The elastic frame 4341 is a rectangular hollow structure. The size of the elastic frame 4341 is larger than The area size of the outer surface 4312 of the piezoelectric vibrator 431 and the hollow structure of the spring frame 4341 can prevent the piezoelectric vibrator 431 from interfering.

The elastic piece 434 has an elastic piece extending arm 4342 on both upper and lower sides in the optical axis direction. Preferably, the number of the elastic piece extending arms 4342 is 2. The elastic piece extending arm 4342 includes a first extending arm 43421 and a second extending arm. Arm 43422. The first extension arm 43421 is located at one end close to the base 411. The first extension arm 43421 extends in the optical axis direction toward the base 411 and extends to the distance between the first extension arm 43421 and the base 411. When the base 411 is in contact with each other, it is bent and extended toward the outside of the elastic piece 434, and the bending angle is 90°. At this time, the bending surface is always in contact with the upper surface of the base 411, and extends After reaching a certain length, bend and extend in the direction of the optical axis. The bending angle is 90° and the extension direction is away from the base 411. At this time, the bending surface is always aligned with the upper surface of the base 411. Vertical, so that the bent portion of the first extension arm 43421 can form a groove structure. The second extension arm 43422 is located at the far From one end of the base 411, the second extension arm 43422 extends in the optical axis direction away from the base 411, extends to a certain length, and then bends and extends toward the outside of the elastic piece 434, and The bending angle is 90°, and the bending surface at this time is always parallel to the upper surface of the base 411 . The bent portion of the elastic piece extending arm 4342 is embedded in the housing 412 and leaves a certain gap with the housing 412 in the optical axis direction, thereby adjusting the positional relationship of the elastic piece 434 relative to the base 411 .

Each 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 a through-hole structure. The elastic piece positioning hole 4343 is located at the center of the rectangular long side of the elastic piece 434. position, so that the piezoelectric vibrator 431 is also located at the center of the elastic piece 434, so that the elastic piece 434 is easy to install, thereby making the structure of the camera module 10 more stable.

The elastic piece 434 can play a role in fixing and limiting the piezoelectric vibrator 431, and can also provide a certain pre-pressure; on the one hand, the elastic piece frame 4341 can prevent the piezoelectric vibrator 431 from interfering; on the other hand, the elastic piece frame 4341 can prevent the piezoelectric vibrator 431 from interfering. , the elastic piece frame 4341 can prevent the elastic piece 434 from deforming and thus affecting the pre-pressure provided by the elastic piece 434 to the piezoelectric vibrator 431; the elastic piece extension arm 4342 can provide support for the housing 412 and other components. force; the elastic piece 434 makes the piezoelectric vibrator 431 and the piezoelectric friction plate 433 come into contact with the movable carrier 42 .

Continuing to refer to FIG. 3 , FIG. 4 and FIG. 5 , the fixing component 41 further includes an FPC soft board 413 and at least one fixing piece 414 . The FPC soft board 413 is attached to the outside of the elastic piece 434, and the FPC soft plate 413 is located at the groove of the first extension arm 43421 of the elastic piece 434. One end of the FPC soft plate 413 is connected to the The other end of the elastic piece 434 extends and bends along the other direction of the elastic piece 434, and extends along the parallel direction of the other outer side of the base 411. The FPC soft board 413 is perpendicular to the Base 411. A first fixing part 4141 is attached to the outside of the FPC soft board 413. The length and width of the first fixing part 4141 are both greater than the length and width of the FPC soft board 413, so that the FPC soft board 413 can be completely Adhered to the first fixing part 4141, the first fixing part 4141 can play a certain supporting role, and the first fixing part 4141 is also perpendicular to the base 411. A position sensor (the position sensor is not shown in the figure) is placed inside the first fixing member 4141 and the FPC soft board 413. The position sensor is parallel to the optical axis direction, and the position sensor is parallel to the optical axis direction. The position sensor is disposed on one side of the piezoelectric vibrator 431 , and the position sensor can sense the position of the movable carrier 42 . The other side of the unbent end of the FPC soft board 413 is provided with a second fixing part 4142. The size of the second fixing part 4142 is the same as the size of the first fixing part 4141. The second fixing part 4142 is parallel to the direction of the other outer side of the base 411 , and the second fixing part 4142 is also perpendicular to the base 411 . The first fixing part 4141 and the second fixing part 4142 are symmetrically distributed with the piezoelectric vibrator 431 as the center, making the overall structure more stable.

As shown in FIG. 4 , in some embodiments, the guide mechanism 44 includes at least one ball 441 , the ball 441 is disposed on the outer side wall of the movable carrier 42 , and the movable carrier 42 has at least one ball 441 that can accommodate In the carrier ball groove 422 of the ball 441, 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 shell ball of the housing 412. In the groove 4122, the ball 441 can be covered by the carrier ball groove 422 of the movable carrier 42 and the shell ball groove 4122 of the housing 412. The balls 441 are arranged vertically in the direction of the optical axis, and at least one ball 441 is arranged on opposite sides. The ball 441 can move with multiple degrees of freedom. When the carrier ball groove 422 has a direction, the movement trajectory of the ball 441 is limited within the carrier ball groove 422, so it can move on the lens. The component 20 plays a guiding role during movement. Preferably, the number of the carrier ball grooves 422 is two, which are respectively provided on opposite sides of the movable carrier 42 so that the camera module 10 can remain stable. The balls 441 are provided The number is six, wherein each carrier ball groove 422 is provided with three balls 441 inside it, and the three balls 441 are stacked in a vertical direction (parallel to the optical axis direction). It should be noted that, with all The balls 441 on the upper and lower sides of the carrier ball groove 422 are slightly larger than the ball 441 in the middle to reduce the contact points between the middle ball 441 and the carrier ball groove 422 to prevent interference. At the same time, by arranging the balls 441 and utilizing the auxiliary effect of the balls 441, the friction force during movement can be reduced, and the balls 441 are arranged relative to each other so that the camera module 10 can remain stable. The balls 441 are arranged symmetrically with the piezoelectric friction head 432 as the center. Since the piezoelectric vibrator 431 expands and contracts during the movement stroke, the piezoelectric friction head 432 expands and contracts during the movement of the piezoelectric vibrator 431. During the process, the tilting in the elliptical direction is achieved, thereby causing the piezoelectric friction head 432 to generate a tilting moment exerted on the outer wall of the movable carrier 42 during the stroke trajectory, and the balls 441 can disperse the tilting moment, so that The overall structure is more stable. The ball 441 uses rolling friction instead of sliding friction, and uses the ball 441, the carrier ball groove 422, and the housing ball groove 4122 as the guide mechanism 44 to provide greater support for the camera module 10, further maintaining the connection between the piezoelectric vibrator and the camera module 10. Parallelism between the movable carriers.

Taking the piezoelectric actuator 43 as an example, the piezoelectric vibrator 431 is a substrate that has an inverse piezoelectric effect and contracts or expands according to the polarization direction and the electric field direction. It can be made by using single crystal, polycrystalline ceramics, or polymers. polarize the substrate in the thickness direction of the To use, the inverse piezoelectric effect refers to applying an electric field in the polarization direction of the dielectric, and the dielectric undergoes mechanical deformation when a potential difference is generated. The piezoelectric vibrator 431 has the function of ultrasonic oscillation and can achieve elliptical motion on a specially arranged electrode layer. The piezoelectric vibrator 431 is made of PZT material and is connected to the circuit board 31 to achieve circuit conduction, thereby providing power excitation.

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

Referring to Figure 6, let the long side of the rectangle of the piezoelectric vibrator 431 be the X-axis direction, the short side of the rectangle of the piezoelectric vibrator 431 be the Y-axis direction, and be parallel to the optical axis direction and perpendicular to the X and Y axis directions, Z axis direction. The Y-Z plane of the piezoelectric oscillator 431 is divided into four regions. The upper left part is the first region 43131, the upper right part is the second region 43132, the lower right part is the third region 43133, and the lower left part is the fourth region 43134. . Due to the piezoelectric effect of d31, each two areas are grouped in pairs to perform telescopic movement in the X-axis direction. When the first region 43131 and the second region 43132 are a group, and the third region 43133 and the fourth region 43134 are moving in groups, vibration in the Z-axis direction can be achieved; when the first region 43131 and the fourth region 43134 are When one group, the second area 43132 and the third area 43133 move in groups, vibration in the Y-axis direction can be achieved. Assume that the electrode polarization conditions of the first region 43131 and the second region 43132 are +, and the electrode polarization conditions of the third region 43133 and the fourth region 43134 are -; and input the electrodes of the first region 43131 and the third region 43133 into sin. signal, the electrodes in the second area 43132 and the fourth area 43134 input cos signals; therefore, from a waveform perspective, the piezoelectric vibrator 431 uses sin in the first area 43131, cos in the second area 43132, and - in the third area 43133. sin, the fourth region 43134 moves in the -cos state, which will produce the cyclic elongation of the second region 43132 the first region 43131 the fourth region 43134 the third region 43133 the second region 43132..., further allowing the piezoelectric oscillator 431 to achieve periodic Sexual bending, the friction head on the surface of the piezoelectric vibrator 431 will achieve elliptical motion, that is, the superposition of the vibration in the Y-axis direction and the vibration in the Z-axis direction forms an elliptical motion. From the perspective of the Y-Z plane of the piezoelectric vibrator 431, in the existing piezoelectric technology, the height of the piezoelectric vibrator 431 in the Z-axis direction is often very long to ensure that the piezoelectric vibrator 431 has a sufficiently long stroke.

In the embodiment of the present application, in order to make the electrode wiring of the piezoelectric vibrator 431 more reasonable, the piezoelectric vibrator 431 is The first end surface 4313 of the piezoelectric oscillator 431 is a front view for illustration. Continuing to refer to FIG. 6 , the piezoelectric vibrator 431 is equally divided into four regions laterally and longitudinally. The upper left part is the first region 43131 and the upper right part is the second region. 43132, the lower right part is the third area 43133, and the lower left part is the fourth area 43134. Assuming that two wires are drawn from each area, that is, each area has an electrode at its upper and lower ends, then the first area 43131, the second area 43132, the third area 43133, and the fourth area 43134 each have an electrode at the upper and lower ends. Electrodes, 8 electrodes in total. Among them, in order to reduce the number of electrodes, among the four regions, the lower electrodes of the first region 43131 and the second region 43132 and the upper electrodes of the third region 43133 and the fourth region 43134 (a total of 4 electrodes) are merged into a common ground terminal. . When polarizing, the signal wiring situation is: the common ground electrode is connected to the ground, the upper electrode of the first area 43131 and the upper electrode of the second area 43132 are connected to the positive electrode, and the lower electrode of the third area 43133 is connected to the positive electrode. The lower electrode of the fourth area 43134 is connected to the negative electrode; when driving, the common ground electrode is grounded, the upper electrode of the first area 43131 and the lower electrode of the third area 43133 input the sin signal, and the upper end of the second area 43132 The electrode and the lower end electrode of the fourth region 43134 input the cos signal. The driving situation according to this electrode connection method is: assuming that the polarization state of the upper electrode of the first region 43131 is +, then the upper electrode of the second region 43132 is also +, and the lower end of the third region 43133 The electrode and the lower electrode of the fourth region 43134 are -; considering the working conditions of the electrodes in each region after polarization, from a waveform perspective, as shown in Figure 7, the motion signal of the piezoelectric vibrator 431 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 -sin, and the lower electrode of the fourth region 43134 is -cos.

In this embodiment of the present application, the first region 43131 and the third region 43133 of the piezoelectric vibrator 431 are grouped together, and the second region 43132 and the fourth region 43134 are grouped together. The upper end electrode of the region 43131 is connected to the lower end electrode of the third region 43133, and the upper end electrode of the second region 43132 of the piezoelectric vibrator 431 is connected to the lower end electrode of the fourth region 43134, that is, two diagonal lines to each other. The electrodes of the regions are connected; continuing to refer to Figure 7, due to the motion signal of the piezoelectric vibrator 431, that is, the upper end electrode of the first region 43131 is sin, the upper end electrode of the second region 43132 is cos, and the third The lower electrode of the region 43133 is -sin, and the lower electrode of the fourth region 43134 is -cos. Then there is a phase difference of 180° between the first region 43131 and the third region 43133, and the second region 43132 There is a phase difference of 180° from the fourth region 43134, so that the piezoelectric vibrator 431 has a longer stroke when driven, and viewed from the direction of the first end surface 4313 of the piezoelectric vibrator 431, The height of the piezoelectric vibrator 431 is further shortened, which is in line with the miniaturization design of the camera module 10 .

After providing power excitation to the piezoelectric actuator 43, the piezoelectric vibrator 431 undergoes different surface changes in the standing wave or traveling wave state on the Y-axis or Z-axis, thereby driving the piezoelectric friction head 432 Elliptical motion is generated, and due to the frictional contact between the piezoelectric friction head 432 and the piezoelectric friction plate 433, the piezoelectric friction plate 433 moves, thereby driving the movable carrier 42 to move. Specifically, when the piezoelectric actuator 43 is excited by the power supply, the piezoelectric vibrator 431 will produce a telescopic movement form along the Y-axis direction and a stretching movement form along the optical axis direction (Z-axis), so The piezoelectric friction head 432 is driven by the piezoelectric vibrator 431 to make an elliptical motion on the Y-Z axis plane, thereby driving the piezoelectric friction plate 433 to move up and down in the Z-axis direction. The four areas of the piezoelectric vibrator 431 vibrate in turn, that is, the four areas protrude in sequence, and the phase difference of each area differs by 90°. Under the condition that the wave has a certain length, the pair of the piezoelectric vibrator 431 is realized. The electrodes in the diagonal area are connected so that the phase difference in the diagonal area is 180°, that is, an "upside-down" shape. This connection method enables the piezoelectric vibrator 431 to have a large stroke, large thrust, high frequency, and small size. and other advantages.

Therefore, the piezoelectric actuator 43 has a degree of freedom in the Z-axis direction and can drive the movable carrier 42 to move in the Z-axis direction to adjust the relative position between the lens assembly 20 and the photosensitive assembly 30 relationship to achieve AF zoom. Among them, the movable carrier 42 also plays a certain supporting role, which can improve the stability of the movement of the piezoelectric actuator 43 during the optical zoom process and improve the imaging quality.

When the piezoelectric vibrator 431 moves after being energized, it has a certain amplitude within the excitation stroke of the power supply. 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 is smaller. Therefore, the elastic piece The frame 4341 can prevent the piezoelectric vibrator 431 from interfering; and the movement of the piezoelectric vibrator 431 after being energized will also cause the piezoelectric vibrator 431 itself to undergo a certain deformation, and the elastic piece 434 can provide a certain inward potential energy. As a result, the elastic piece 434 and the piezoelectric vibrator 431 are pressed more tightly, thereby reducing the deformation degree of the piezoelectric vibrator 431, so that the piezoelectric vibrator 431 can still return to its original position after vibration. The following implementation One vibration.

From an electrode level, as shown in Figures 8 and 9, the four regions of the piezoelectric vibrator 431 can be further divided into a first phase electrode 43135, a second phase electrode 43136, a third phase electrode 43137 and a fourth phase electrode. Phase electrode 43138. Wherein, the first region 43131 of the piezoelectric vibrator 431 has a first phase electrode 43135 and a second phase electrode 43136, and 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 electrodes 43135, The second phase electrode 43136, the third phase electrode 43137 and the fourth phase electrode 43138 are stacked on each other in the long side direction of a rectangle, wherein the second phase electrode 43136 is connected to the first region 43131 and the third region of the piezoelectric vibrator 431. Two regions 43132, the second phase electrode 43136 is a common potential electrode arranged in the long side direction of a rectangle; the fourth phase electrode 43138 is connected to the third region 43133 and the fourth region 43134 of the piezoelectric vibrator 431, the The fourth phase electrode 43138 is a common potential electrode arranged in a rectangular long side direction. This design can reduce the number of stacked electrode layers and thereby reduce the electrode size. In addition, the piezoelectric oscillator 431 also has at least one substrate 4315. The substrate 4315 is disposed on the inner side 4311 and the outer side 4312 of the piezoelectric oscillator 431 in the short side direction of the rectangle, and further communicates with the piezoelectric oscillator 431. The entire electrode layer, and the substrate 4315 being arranged on the side of the piezoelectric vibrator 431 can further reduce the size of the electrode and rationally utilize the space. 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. 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 to ensure that two diagonal lines of the piezoelectric vibrator 431 are mutually diagonal. The electrodes in each area are connected to each other, thereby reducing the size of the piezoelectric vibrator 431 while ensuring that the piezoelectric vibrator 431 has advantages such as a large stroke.

In addition, the piezoelectric vibrator 431 is fixed by the elastic piece positioning hole 4343 of the elastic piece 434, wherein the elastic piece positioning hole 4343 is provided in the middle section area of the outer surface 4312 of the piezoelectric vibrator 431, and is fixed in this way. When , the resonant frequencies of the piezoelectric vibrator 431 in the Y-axis and Z-axis directions are almost the same, and the movement trajectory of the piezoelectric friction head 432 is an elliptical motion, thereby driving the movable carrier 42 to move in the Z-axis direction. movement to achieve AF zoom.

The basic principles, main features and advantages of the present invention are described above. Those skilled in the industry should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and descriptions is only the principle of the present invention. The present invention may also have various modifications without departing from the spirit and scope of the present invention. changes and improvements that fall within the scope of the claimed invention. The scope of protection required for the present invention is defined by the appended claims and their equivalents.

Claims

A piezoelectric motor, characterized by including:

A fixing component, the fixing component includes a base and a shell, wherein the shell is located above the base;

Movable carrier, the movable carrier is arranged above the base;

Piezoelectric actuator, the piezoelectric actuator includes a piezoelectric vibrator and a spring piece, wherein one side of the spring piece is disposed on a surface of the piezoelectric vibrator, and the other side of the spring piece is connected to the housing; The elastic piece is in contact with the piezoelectric oscillator, and the elastic piece is in contact with the two rectangular short sides of the piezoelectric oscillator; wherein, the rectangular long side of the elastic piece is opposite to the rectangular long side of the piezoelectric oscillator. vertical.

A guide mechanism maintains the parallelism of the piezoelectric vibrator and the movable carrier.
The piezoelectric motor of claim 1, wherein the piezoelectric actuator further includes:

A piezoelectric friction head is provided at the center of a surface of the piezoelectric vibrator.
The piezoelectric motor according to claim 2, wherein the piezoelectric actuator further includes: a piezoelectric friction plate, the piezoelectric friction plate abuts the piezoelectric friction head.
The piezoelectric motor according to claim 3, wherein the piezoelectric friction plate is arranged parallel to one surface of the piezoelectric vibrator, and the piezoelectric friction head is located at the center of the piezoelectric friction plate.
The piezoelectric motor according to claim 1, wherein the elastic piece has an elastic piece frame, the middle area of the elastic piece frame is a rectangular hollow structure, and the size of the elastic piece frame is larger than the area size of the surface of the piezoelectric vibrator.
The piezoelectric motor according to claim 5, wherein the elastic piece frame of the elastic piece provides pre-pressure on at least two rectangular short sides of the piezoelectric vibrator.
The piezoelectric motor according to claim 1, wherein the pre-compression edge of the elastic piece and the piezoelectric vibrator is parallel to the driving direction of the piezoelectric vibrator.
The piezoelectric motor according to claim 1, wherein the elastic piece further includes at least one elastic piece extending arm, the elastic piece extending arm has a groove structure, the elastic piece extending arm is embedded in the housing and connected with the housing. Leave some space.
The piezoelectric motor according to claim 1, wherein the elastic piece also has at least one elastic piece positioning hole, and the elastic piece is fixed to the piezoelectric vibrator through the elastic piece positioning hole, and the elastic piece positioning hole is located at the piezoelectric vibrator. The amplitude of the piezoelectric vibrator in the long side direction of the rectangle is the smallest.
The piezoelectric motor according to claim 8, wherein the fixed component further includes an FPC soft board, the FPC soft board is arranged in the groove structure of the elastic piece extension arm, and the FPC soft board is attached to the Describe shrapnel.
A piezoelectric actuator, characterized by including:

A piezoelectric vibrator, the piezoelectric vibrator has an electrode, and the piezoelectric vibrator is a cuboid;

A piezoelectric friction head, the piezoelectric friction head is disposed on a surface of the piezoelectric vibrator;

A piezoelectric friction plate, the piezoelectric friction plate is in contact with the piezoelectric friction head;

An elastic piece, the elastic piece is arranged on the other surface of the piezoelectric vibrator;

Wherein, the plane formed by the rectangular short side of the piezoelectric oscillator is divided into four regions, and the diagonal regions are connected by electrodes.
The piezoelectric actuator according to claim 11, wherein the four regions of the piezoelectric vibrator are a first region, a second region, a third region and a fourth region in order in a clockwise direction.
The piezoelectric actuator according to claim 11, wherein each of the four regions of the piezoelectric vibrator has electrodes at upper and lower ends.
The piezoelectric actuator according to claim 12, wherein the upper end electrode of the first region of the piezoelectric vibrator is connected to the lower end electrode of the third region, and the upper end electrode of the second region of the piezoelectric vibrator is connected to The lower end electrodes of the fourth area are connected, that is, the electrodes of the two areas that are diagonal to each other are connected.
The piezoelectric actuator according to claim 11, wherein the elastic piece further has at least one elastic piece positioning hole, and the elastic piece is fixed to the piezoelectric oscillator through the elastic piece positioning hole, and the piezoelectric oscillator The resonant frequency in the direction of the long side of the rectangle is the same as the direction of the short side of the rectangle.
The piezoelectric actuator according to claim 11, wherein the piezoelectric vibrator further includes a first phase electrode, a second phase electrode, a third phase electrode and a fourth phase electrode. Wherein, the first region of the piezoelectric oscillator has a first phase electrode and a second phase electrode, the second region of the piezoelectric oscillator has a second phase electrode and a third phase electrode, and the third region of the piezoelectric oscillator has a first phase electrode and a second phase electrode. A region has a first phase electrode and a fourth phase electrode, and a fourth region of the piezoelectric vibrator has a third phase electrode and a fourth phase electrode.
The piezoelectric actuator according to claim 16, wherein the first phase electrode, the second phase electrode, the third phase electrode and the fourth phase electrode of the piezoelectric vibrator are stacked on each other in a rectangular long side direction.
The piezoelectric actuator according to claim 16, wherein the second phase electrode of the piezoelectric oscillator is connected to the first region and the second region of the piezoelectric oscillator with a common potential electrode, and the piezoelectric oscillator The fourth phase electrode is connected to the third region and the fourth region of the piezoelectric oscillator with a common potential electrode.
The piezoelectric actuator according to claim 16, wherein the piezoelectric oscillator further has at least one substrate, the substrate is disposed on a surface of the piezoelectric oscillator in a rectangular short side direction, and the substrate communicates with the piezoelectric oscillator. The electrode layer of the piezoelectric vibrator.
The piezoelectric actuator according to claim 19, wherein the substrate includes a first substrate and a second substrate, the first substrate is connected to the first phase electrode of the first region of the piezoelectric vibrator. and a first phase electrode in the third region, and the second substrate is connected to the third phase electrode in the second region and the third phase electrode in the fourth region of the piezoelectric vibrator.