CN117761858A - Driving device and camera module - Google Patents

Abstract

The application discloses drive arrangement and module of making a video recording, drive arrangement includes: a fixing part; a movable portion movably provided in the fixed portion; and a driving part disposed between the fixed part and the movable part, the driving part driving the movable part to move in a first direction or a second direction, the first direction being opposite to the second direction, wherein a speed at which the driving part drives the movable part to move in the first direction is greater than a speed at which the driving part drives the movable part to move in the second direction. In the technical scheme, the driving requirement of the camera module on optical performance adjustment can be met, and the camera module is suitable for quick focusing so as to realize clear imaging.

Description

Driving device and camera module

Technical Field

The application relates to the technical field of camera modules, in particular to a driving device and a camera module.

Background

With the popularity of mobile electronic devices, related technologies of camera modules used for mobile electronic devices to assist users in capturing images (e.g., videos or images) have been rapidly developed and advanced, and in recent years, camera modules have been widely used in various fields such as medical, security, industrial production, etc.

In order to meet the increasingly wide market demands, high-pixel and small-size imaging modules are irreversible development trends. The increased size of the imaging lens due to the need to use high resolution image sensors presents new challenges for driving elements for driving optical components for optical performance adjustment.

Therefore, there is a need for a new driving scheme for a camera module that meets the driving requirement of the camera module for optical performance adjustment, and also meets the development requirements of light and thin camera modules.

Disclosure of Invention

An object of the present application is to provide a driving device and a camera module, which overcome the defects of the prior art, can meet the driving requirement of the camera module on optical performance adjustment, and is suitable for realizing clear imaging.

According to an aspect of the present application, there is provided a driving apparatus comprising:

a fixing part;

a movable portion movably provided in the fixed portion; and

and a driving part arranged between the fixed part and the movable part, wherein the driving part drives the movable part to move along a first direction or a second direction, and the first direction is opposite to the second direction, and the speed of the driving part driving the movable part to move along the first direction is greater than the speed of the driving part driving the movable part to move along the second direction.

In some embodiments, the driving part includes a piezoelectric vibrator and a friction driving part fixed to the piezoelectric vibrator, the friction driving part being eccentrically disposed on the piezoelectric vibrator in a height direction.

In some embodiments, the piezoelectric vibrator includes two bending modes of a first bending mode and a second bending mode, and the driving part drives the movable part to move in the first direction or the second direction in the two bending modes, respectively.

In some embodiments, the distance from the friction driving portion to the top end of the piezoelectric vibrator is smaller than the distance from the friction driving portion to the bottom end of the piezoelectric vibrator in the height direction.

In some embodiments, the movable portion includes a movable carrier and a friction plate sandwiched between the movable carrier and the friction drive portion, the friction drive portion being frictionally coupled to the friction plate.

In some embodiments, the friction drive is less in height from the top end of the friction plate than from the bottom end of the friction plate.

In some embodiments, the driving device further includes a pre-compression member disposed between the fixed portion and the driving portion, the pre-compression generated by the pre-compression member maintaining frictional contact between the friction driving portion and the friction plate at all times.

In some embodiments, the pre-pressure component includes two fixing ends and a connecting section integrally connected between the two fixing ends, the two fixing ends are fixed on the fixing portion, a certain gap is formed between the connecting section and the fixing portion, and the piezoelectric vibrator is disposed on a side of the connecting section away from the fixing portion.

In some embodiments, the driving device further comprises a guiding device disposed between the fixed portion and the movable portion, the movable portion being clamped between the pre-compression member and the guiding device.

According to a second aspect of the present application, there is provided a camera module, comprising:

an optical lens;

a photosensitive assembly, the optical lens being held on a photosensitive path of the photosensitive assembly; and

and a driving device, wherein the optical lens is mounted on the movable part of the driving device.

Compared with the prior art, the application has at least one of the following technical effects:

1. the piezoelectric vibrator vibrates in two bending modes, so that the friction driving part is driven to do elliptical motion along two directions respectively, the driving device is used for driving the optical lens to move along the optical axis direction towards two opposite directions, and the optical focusing function of the camera module is realized.

2. The friction driving part is eccentrically arranged on the piezoelectric vibrator along the length direction of the piezoelectric vibrator, so that the driving device drives the optical lens to move along the optical axis in two opposite directions at different speeds.

3. The optical lens is driven to move along the optical axis towards the object side more rapidly, so that the quick focusing of the camera module is realized.

Additional embodiments and features are set forth in part in the description which follows and in part will become apparent to those skilled in the art upon examination of the specification or may be learned by practice of the disclosed subject matter. A further understanding of the nature and advantages of the present disclosure may be realized by reference to the remaining portions of the specification and the drawings which form a part of this application.

Drawings

Fig. 1A is a schematic structural view of a piezoelectric actuator according to an embodiment of the present application.

Fig. 1B is a schematic structural view of another example of a piezoelectric actuator according to an embodiment of the present application.

Fig. 2A and 2B are side and top views of a piezoelectric actuator according to an embodiment of the present application.

Fig. 3A and 3B are schematic views of two bending modes of a piezoelectric vibrator when the piezoelectric actuator according to an embodiment of the present application is operated.

Fig. 4 is a schematic diagram of four area distribution of piezoelectric vibrators of a piezoelectric actuator according to an embodiment of the present application.

Fig. 5A is a schematic structural view of a piezoelectric vibrator and a multilayer electrode layer inside thereof according to an embodiment of the present application.

Fig. 5B is an exploded schematic view of a piezoelectric vibrator according to an embodiment of the present application.

Fig. 6 is a schematic structural view of a multilayer electrode layer inside a piezoelectric vibrator according to an embodiment of the present application.

Fig. 7 is a schematic polarization diagram of a piezoelectric vibrator according to an embodiment of the present application.

Fig. 8 is a schematic diagram of a mechanism of a drive motor assembly according to an embodiment of the present application.

Fig. 9 is a schematic structural diagram of an image capturing module according to an embodiment of the present application.

Fig. 10 is a schematic top view of a drive device according to an embodiment of the present application.

Fig. 11 is an exploded schematic view of a driving device according to an embodiment of the present application.

Fig. 12 is a schematic cross-sectional view of an imaging module according to an embodiment of the present application.

Fig. 13 is a schematic cross-sectional view of a drive device according to an embodiment of the present application.

Detailed Description

The present application will be further described with reference to the specific embodiments, and it should be noted that, on the premise of no conflict, new embodiments may be formed by any combination of the embodiments or technical features described below.

The term "comprising" is open ended. As used in the appended claims, the term does not exclude additional structures or steps.

In the description of the present application, it should be noted that, for the azimuth terms 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 application and simplifying the description, and it is not to be construed as limiting the specific protection scope of the present application that the device or element referred to must have a specific azimuth configuration and operation, as indicated or implied.

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.

It is noted that, as used in this application, the terms "substantially," "about," and the like are used as terms of a table approximation, not as terms of a table level, and are intended to illustrate inherent deviations in measured or calculated values that would be recognized by one of ordinary skill in the art.

In the description of the present application, 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 terms in this application will be understood by those of ordinary skill in the art as the case may be.

Various units, circuits, or other components may be described or described as "configured to" perform a task or tasks. In such contexts, "configured to" implies that the structure (e.g., circuitry) is used by indicating that the unit/circuit/component includes the structure (e.g., circuitry) that performs the task or tasks during operation. . Further, "configured to" may include a general-purpose structure (e.g., a general-purpose circuit) that is manipulated by software and/or firmware to operate in a manner that is capable of performing one or more tasks to be solved. "configured to" may also include adjusting a manufacturing process (e.g., a semiconductor fabrication facility) to manufacture a device (e.g., an integrated circuit) suitable for performing or executing one or more tasks.

The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the specification and the appended claims, the singular forms "a," "an," and "the" are intended to cover the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

As used herein, the term "if" may be interpreted to mean "when..or" at..times "or" in response to a determination "or" in response to detection "depending on the context. Similarly, the phrase "if a condition or event is identified" or "if a condition or event is detected" may be interpreted to mean "upon identification of the condition or event," or "upon detection of the condition or event, depending on the context.

Exemplary piezoelectric actuator

The piezoelectric actuator is an actuator which applies the characteristics of deformation (extension and contraction) of the applied voltage of piezoelectric ceramics, is an actuator which converts electric energy into mechanical energy, is widely used in equipment such as camera modules and the like, and has the advantages of simple structure, high precision, quick response, low power consumption, good stopping and holding capacity and the like. Fig. 1A to 7 illustrate the structure of the piezoelectric actuator and the driving principle thereof described in the present application.

As shown in fig. 1A and 1B, the piezoelectric actuator 10 described in the present application includes a piezoelectric vibrator 11 and a friction drive portion 12 drivingly connected to the piezoelectric vibrator 11, the friction drive portion 12 being fixed to the piezoelectric vibrator 11, whereby the friction drive portion 12 changes positional information in accordance with deformation of the piezoelectric vibrator 11. The friction driving part 12 moves by the driving of the piezoelectric vibrator 11, so that the piezoelectric actuator 10 can drive the movement of the driven object by the friction force between the friction driving part 12 and the driven object. In a specific example, the friction driving unit 12 generates an elliptical orbit-like two-dimensional track along with the deformation of the piezoelectric vibrator 11, and the friction driving unit 12 reciprocates under the drive of the piezoelectric vibrator 11.

Since the piezoelectric actuator 10 drives the movement of the driven object by the frictional force between the friction driving part 12 and the driven object, the material of the friction driving part 12 and the shape thereof become important. The friction driving portion 12 is made of a material having preferable friction performance and durability, and may be made of a metal oxide material (e.g., zirconia, alumina, etc.), for example. The shape of the friction driving portion 12 may be hemispherical, cylindrical, semi-cylindrical, mesa-shaped, rectangular parallelepiped-shaped, or the like, for example, as shown in fig. 1A, in one example of the present application, the shape of the friction driving portion 12 is cylindrical, and a side surface of the cylindrical friction driving portion 12 is fixed to one side surface of the piezoelectric vibrator 11 by, for example, bonding, at which time the friction driving portion 12 may be in friction contact with the driven object line, and in another embodiment of the present application, the cylindrical friction driving portion 12 is fixed to one side surface of the piezoelectric vibrator 11 by its bottom surface, so that the friction driving portion 12 may be in friction contact with the driven object surface; in another example of the present application, as shown in fig. 1B, the friction driving portion 12 has a hemispherical shape, and the bottom surface of the hemispherical friction driving portion 12 is fixed to one side surface of the piezoelectric vibrator 11 by, for example, bonding, and at this time, the friction driving portion 12 may be in point friction contact with the driven object.

Fig. 2A shows a side view of the piezoelectric actuator 10 shown in fig. 1A, and as shown in fig. 1A and 2A, the friction driving portion 12 is fixed to the front surface 114 of the piezoelectric vibrator 11 (i.e., the first side surface of the piezoelectric vibrator 11) in the thickness direction of the piezoelectric vibrator 11 (i.e., the Y-axis direction shown in fig. 1A), so that the piezoelectric actuator 10 is adapted to drive the driven object to move in the Z-axis direction. Note that, in the present application, as shown in the coordinate axis illustrated in fig. 1A, the thickness direction of the piezoelectric actuator 10 is the Y-axis direction, the driving direction of the piezoelectric actuator 10 is the Z-axis direction, and the directions perpendicular to the Y-axis direction and the Z-axis direction are the X-axis directions, wherein the piezoelectric vibrator 11 is elongated, and the length dimension of the piezoelectric vibrator 11 in the Z-axis direction is longest, and therefore, the Z-axis direction may also be referred to as the length direction of the piezoelectric vibrator 11 (the piezoelectric actuator 10), while the Y-axis direction is referred to as the thickness direction of the piezoelectric vibrator 11 (the piezoelectric actuator 10), and the X-axis direction may be referred to as the width direction of the piezoelectric vibrator 11 (the piezoelectric actuator 10). The longitudinal direction of the cylindrical friction driving portion 12 illustrated in fig. 1A is perpendicular to the longitudinal direction of the piezoelectric vibrator 11, and the cylindrical friction driving portion 12 extends in the X-axis direction.

Further, the piezoelectric vibrator 11 has a rectangular parallelepiped or substantially rectangular parallelepiped shape, and the piezoelectric vibrator 11 has six sides of a first side, a second side, a third side, a fourth side, a fifth side, and a sixth side. The piezoelectric vibrator 11 includes a front surface 114 and a back surface which are disposed opposite to each other in the thickness direction, the front surface 114 of the piezoelectric vibrator 11 on which the friction driving portion 12 is disposed is a first side surface, the back surface opposite to the front surface 114 of the piezoelectric vibrator 11 is a second side surface, the third side surface and the fourth side surface are adjacent to the first side surface and the second side surface, respectively, and are symmetrical with respect to the Z-axis direction, the fifth side surface and the sixth side surface are adjacent to the remaining four side surfaces, respectively, and are symmetrical with respect to the X-axis direction, and the fifth side surface and the sixth side surface are two side surfaces having the smallest area among the six side surfaces of the piezoelectric vibrator 11, as indicated by the dimensions shown in fig. 1A.

In the present application, further, the friction driving portion 12 is eccentrically disposed on the first side surface (i.e., the front surface 114) of the piezoelectric vibrator 11 along the longitudinal direction of the piezoelectric vibrator 11. Fig. 2B illustrates the front surface 114 of the piezoelectric actuator 10 shown in fig. 1A from a top view, in one example, the front surface 114 of the piezoelectric vibrator 11 has a rectangular or nearly rectangular shape, the front surface 114 of the piezoelectric vibrator 11 has two long sides 1141 that are relatively distributed and two short sides that are relatively distributed, wherein the two short sides include a first short side 1142 and a second short side 1143, and the friction driving portion 12 is eccentrically disposed on the first side surface of the piezoelectric vibrator 11 at a position closer to the first short side 1142. In one specific example, the piezoelectric actuator 10 is symmetrical about the length direction, while it is asymmetrical about the width direction.

Next, a driving process of the piezoelectric actuator 10 will be described. In operation of the piezoelectric actuator 10 described herein, the piezoelectric vibrator 11 includes two bending modes: a first bending mode and a second bending mode, the first bending mode and the second bending mode being implemented by inputting circuit signals of different frequencies. The piezoelectric vibrator 11 vibrates in two bending modes, so that the eccentrically disposed friction driving portions 12 are respectively driven to make elliptical motions in two directions, and the piezoelectric actuator 10 is further driven to move the driven object in two opposite directions of the first direction and the second direction in the two bending modes, respectively.

With further reference to fig. 3A, 3B and 4, specifically, fig. 3A and 3B illustrate two bending modes of the piezoelectric vibrator 11 when the piezoelectric actuator 10 is operated, and fig. 4 illustrates four regions of the piezoelectric vibrator 11 of the piezoelectric actuator 10. Fig. 3A illustrates a first bending mode in which the piezoelectric vibrator 11 is bending-vibrated in a mode of one peak or one trough in the thickness direction thereof, so that the friction driving portion 12 eccentrically fixed to the piezoelectric vibrator 11 can drive the driven object to move in the first direction. The first direction refers to the eccentric direction of the friction driving portion 12, that is, the direction in which the friction driving portion 12 is eccentric, that is, the direction in which the center of the piezoelectric vibrator 11 is directed toward the friction driving portion 12 in the length direction, that is, the direction in which the friction driving portion 12 shown in fig. 2B is directed toward the nearest short side (first short side 1142) adjacent thereto.

In the first bending mode, the piezoelectric vibrator 11 vibrates in a mode bending of one peak or one trough in the thickness direction thereof. In other words, the piezoelectric vibrator 11 is bent upward from the flat state (M1) to the first bending state (M2) having only one peak, then the piezoelectric vibrator 11 is bent downward to the second bending state (M3) having only one trough after being again bent straight, and then the piezoelectric vibrator 11 is again bent straight and the above bending process is repeated, thereby forming bending vibration of the piezoelectric vibrator 11 in the first bending mode. In the first bending mode, the bending state of the piezoelectric vibrator 11 includes a first bending state and a second bending state, and the first bending state of the piezoelectric vibrator 11 is symmetrical with the second bending state of the piezoelectric vibrator 11 in the longitudinal direction. In this application, the straight state refers to a state where the bending state is relatively straight, and is not a completely straight state. In the first bending mode, the piezoelectric vibrator 11 has the maximum amplitude at only one point in the bending state, and the piezoelectric vibrator 11 is symmetrically bent and vibrated, so that the driven object is driven to move in the eccentric direction of the friction driving part 12 by the eccentrically arranged friction driving part 12.

With continued reference to fig. 4, the piezoelectric vibrator 11 includes a first bending portion 115 and a second bending portion 116 connected in series in the longitudinal direction, wherein the first bending portion 115 is located below the friction driving portion 12. Further, in the width direction (i.e., the X-axis direction), the piezoelectric vibrator 11 is divided into four regions, and the piezoelectric vibrator 11 includes a first region 115a, a second region 115b, a third region 116c, and a fourth region 116d, wherein the first region 115a and the second region 115b are located below the friction driving section 12, and the third region 116c and the fourth region 116d are adjacent to the first region 115a and the second region 115b, respectively, and are the first region 115a, the second region 115b, the fourth region 116d, and the third region 116c, respectively, in the counterclockwise direction. The first curved portion 115 includes a first region 115a and a second region 115b, the first region 115a and the second region 115b being parallel to each other; the second bending portion 116 includes a third region 116c and a fourth region 116d, and the third region 116c and the fourth region 116d are parallel to each other.

In the first bending mode, after a voltage is applied to the piezoelectric vibrator 11, the first region 115a is elongated in the length direction, the second region 115b is contracted in the length direction, the third region 116c is elongated in the length direction, and the fourth region 116d is contracted in the length direction, thereby realizing the first bending state of the piezoelectric vibrator 11; when the direction of the applied voltage is changed, the first region 115a is contracted in the longitudinal direction, the second region 115b is elongated in the longitudinal direction, the third region 116c is contracted in the longitudinal direction, and the fourth region 116d is elongated in the longitudinal direction, thereby realizing the second bending state of the piezoelectric vibrator 11. The piezoelectric vibrator 11 can be switched between the first bending state and the second bending state by repeatedly changing the direction of the voltage, thereby realizing bending vibration with only one wave crest or one wave trough. When the piezoelectric vibrator 11 is in bending vibration in the first bending mode, the first bending portion 115 and the second bending portion 116 are axisymmetric to each other, and after the first bending portion 115 is deformed, the first bending portion and the second bending portion 116 are deformed to form a peak or a trough of the piezoelectric vibrator 11 in a bending state.

Fig. 3B partially illustrates a second bending mode in which the piezoelectric vibrator 11 is bending-vibrated in a mode of one peak and one trough in the thickness direction thereof, so that the friction driving portion 12 eccentrically fixed to the piezoelectric vibrator 11 can drive the driven object to move in the second direction. The second direction is opposite to the first direction, and the second direction is a direction in which the friction driving portion 12 points to the center of the piezoelectric vibrator 11 in the longitudinal direction, that is, a direction in which the friction driving portion 12 points to the farthest short side (second short side 1143) adjacent thereto shown in fig. 2B.

In the second bending mode, the piezoelectric vibrator 11 vibrates in a mode bending of one peak and one trough in the thickness direction thereof. In other words, the piezoelectric vibrator 11 is changed from the flat state (N1) to the third bending state (N2) having only one peak and one trough, then the piezoelectric vibrator 11 is changed to the flat state again and then is bent in the opposite direction to the fourth bending state (N3) having only one peak and one trough, and then the piezoelectric vibrator 11 is changed to the flat state again and the above bending process is repeated, thereby forming bending vibration of the piezoelectric vibrator 11 in the second bending mode. In the second bending mode, the bending states of the piezoelectric vibrator 11 include a third bending state and a fourth bending state, and the third bending state of the piezoelectric vibrator 11 is symmetrical to the fourth bending state of the piezoelectric vibrator 11 in the longitudinal direction. In this application, the straight state refers to a state where the bending state is relatively straight, and is not a completely straight state. In the second bending mode, the piezoelectric vibrator 11 has the maximum amplitude at only two places in the bending state, the piezoelectric vibrator 11 is rotationally symmetric to perform bending vibration, and the friction driving portion 12 is provided between the peak and the trough of the piezoelectric vibrator 11 in the second bending mode, so that the driven object is driven to move in the opposite direction (second direction) of the eccentric direction of the friction driving portion 12 by the eccentrically provided friction driving portion 12.

In the second bending mode, after a voltage is applied to the piezoelectric vibrator 11, the first region 115a is elongated in the length direction, the second region 115b is contracted in the length direction, the third region 116c is contracted in the length direction, and the fourth region 116d is elongated in the length direction, thereby realizing a third bending state of the piezoelectric vibrator 11; when the direction of the applied voltage is changed, the first region 115a is contracted in the longitudinal direction, the second region 115b is elongated in the longitudinal direction, the third region 116c is elongated in the longitudinal direction, and the fourth region 116d is contracted in the longitudinal direction, thereby realizing the fourth bending state of the piezoelectric vibrator 11. The piezoelectric vibrator 11 can be switched between the third bending state and the fourth bending state by repeatedly changing the direction of the voltage, thereby realizing bending vibration having only one peak and one trough. When the piezoelectric vibrator 11 is in bending vibration in the second bending mode, the first bending part 115 and the second bending part 116 are rotationally symmetrical, one wave crest of the piezoelectric vibrator 11 in the bending state is formed after the first bending part 115 is deformed, one wave trough of the piezoelectric vibrator 11 in the bending state is formed after the second bending part 116 is deformed, and the third bending state is formed; alternatively, the first bending portion 115 deforms to form a trough of the piezoelectric vibrator 11 in the bending state, and the second bending portion 116 deforms to form a peak of the piezoelectric vibrator 11 in the bending state, that is, a fourth bending state.

Specifically, in order to allow the friction driving unit 12 on the piezoelectric vibrator 11 to move in two opposite directions in the first bending mode and the second bending mode, it is necessary to simultaneously set the friction driving unit 12 eccentrically between the front surface 114 of the piezoelectric vibrator 11 and set the friction driving unit 12 between the peaks and the valleys of the piezoelectric vibrator 11 in the second bending mode. Therefore, in the present application, the friction drive portion 12 is fixed to the front face 114 of the piezoelectric vibrator 11 in the thickness direction, and the friction drive portion 12 is located between one-fourth and one-half of the piezoelectric vibrator 11 in the length direction. As shown in fig. 2B, 3A, and 3B, a broken line P illustrates a half of the piezoelectric vibrator 11 in the length direction, and a broken line Q illustrates a quarter of the piezoelectric vibrator 11 in the length direction, and the friction drive portion 12 is located at a position between the broken line Q and the broken line P.

In one example, the friction driving portion 12 is located between one quarter and one half of the piezoelectric vibrator 11 in the length direction, that is, the friction driving portion 12 is disposed between one of the maximum amplitude of the piezoelectric vibrator 11 in the first bending mode and the maximum amplitude of the two positions of the piezoelectric vibrator 11 in the second bending mode. As illustrated in fig. 3A and 3B, the friction driving portion 12 is provided on one side of the highest point of the piezoelectric vibrator 11 in the first bending mode, and the friction driving portion 12 is provided on the opposite side of the highest point of the piezoelectric vibrator 11 in the third bending mode.

When the friction driving portion 12 is located between a quarter and a half of the piezoelectric vibrator 11 in the length direction, in the first bending mode, in the first bending state, the friction driving portion 12 is located at one side of the peak of the piezoelectric vibrator 11, the piezoelectric actuator 10 drives the driven object to move in the first direction through the friction driving portion 12, wherein the direction in which the peak of the piezoelectric vibrator 11 points to the friction driving portion 12 is the first direction; in the second bending mode, in the third bending state, the friction driving section 12 is located on the opposite side of the peak of the piezoelectric vibrator 11, and the piezoelectric actuator 10 drives the driven object to move in the second direction by the friction driving section 12, wherein the direction in which the friction driving section 12 points to the peak of the piezoelectric vibrator 11 is the second direction, which is opposite to the first direction.

In this application, in order to achieve the deformation of the first bending portion 115 and the second bending portion 116 of the piezoelectric vibrator 11 in different bending modes, piezoelectric layers may be disposed in the first region 115a, the second region 115b, and the third region 116c and the fourth region 116d of the first bending portion 115, respectively, and then piezoelectric layer electrical signals of the first region 115a, the second region 115b, the third region 116c, and the fourth region 116d may be provided, respectively, so as to control the deformation states of the first region 115a, the second region 115b, the third region 116c, and the fourth region 116d, respectively. However, in this embodiment, the piezoelectric actuator 10 needs to have a high voltage in the electric signal, which affects the power consumption of the electronic device, and a scheme capable of reducing the voltage is desired.

Fig. 5A shows a schematic view of a laminated piezoelectric vibrator according to the present application, fig. 5B shows an exploded schematic view of the laminated piezoelectric vibrator shown in fig. 5A, and fig. 6 shows a schematic view of a multi-layer electrode layer of the laminated piezoelectric vibrator shown in fig. 5A. As shown in fig. 5A, 5B and 6, the piezoelectric vibrator 11 includes a plurality of ceramic layers 111, a plurality of electrode layers 112 disposed between adjacent ceramic layers 111 at intervals, and a side electric conduction portion 113 electrically connected to the plurality of electrode layers 112, the side electric conduction portion 113 providing an electric signal of the plurality of electrode layers 112 to generate an electric field between the adjacent electrode layers 112, the ceramic layers 111 being deformed (elongated or contracted) by the electric field of the adjacent electrode layers 112. By providing the plurality of electrode layers 112, the voltage required to drive the flexural vibration of the piezoelectric vibrator 11 is reduced, and the number of layers of the electrode layers 112 and the number of layers of the ceramic layers 111 are selected according to specific requirements, and in one example of the present application, the number of layers of the ceramic layers 111 is 5 or more. The ceramic layer 111 is made of a ceramic material having a piezoelectric effect, and may be PZT piezoelectric ceramic, for example; the electrode layer 112 is made of a material suitable for electric conduction, for example, it may be copper, gold, silver alloy, or the like; the side conductive portion 113 is made of a material suitable for electrical conduction, and may be copper, gold, silver alloy, or the like, for example; the fixation between the multilayer ceramic layer 111 and the multilayer electrode layer 112 can be achieved by adopting a ceramic co-firing process, a layer of ceramic slurry is laid, a layer of electrode slurry is laid, and then the layers are heated and fired together to form the laminated piezoelectric vibrator 11.

With continued reference to fig. 5A, 5B and 6, the multi-layer electrode layer 112 includes at least one first electrode layer 112a, at least one second electrode layer 112B, at least one third electrode layer 112c and at least one fourth electrode layer 112d according to functional divisions. Wherein, the at least one first electrode layer 112a and the at least one second electrode layer 112b are symmetrically arranged with respect to the width direction (X-axis direction) of the piezoelectric vibrator 11, the at least one first electrode layer 112a and the at least one second electrode layer 112b are short electrode layers with shorter lengths, and the at least one first electrode layer 112a and the at least one second electrode layer 112b are located on the same layer; the at least one third electrode layer 112c and the at least one fourth electrode layer 112d are symmetrically disposed about the length direction (Z-axis direction) of the piezoelectric vibrator 11, the at least one third electrode layer 112c and the at least one fourth electrode layer 112d are disposed on different layers, respectively, and the at least one third electrode layer 112c and the at least one fourth electrode layer 112d are long electrode layers with longer lengths. Thus, both sides of each third electrode layer 112c and each fourth electrode layer 112d are provided with one long electrode layer formed of the first electrode layer 112a or the second electrode layer 112b, respectively.

In one specific example, the at least one first electrode layer 112a is disposed in the first region 115a and the second region 115b of the first bending portion 115, the at least one second electrode layer 112b is disposed in the third region 116c and the fourth region 116d of the second bending portion 116, the at least one third electrode layer 112c is disposed in the second region 115b of the first bending portion 115 and the fourth region 116d of the second bending portion 116, and the at least one fourth electrode layer 112d is disposed in the first region 115a of the first bending portion 115 and the third region 116c of the second bending portion 116. With such an arrangement, the deformation of the first region 115a, the second region 115b, the third region 116c, and the fourth region 116d can be controlled by electric signals, respectively, and thus the bending mode of the piezoelectric vibrator 11 can be controlled.

To facilitate electrical connection of the multilayer electrode layer 112 on the piezoelectric vibrator 11 to an external device, electrical conduction to the external device is performed through the side electrical conduction portion 113. The side electric conduction portion 113 includes a first side electric connection portion 113a, a second side electric connection portion 113b, a third side electric connection portion 113c, and a fourth side electric connection portion 113d. In one example, the first side electrical connection portion 113a, the second side electrical connection portion 113b, the third side electrical connection portion 113c, and the fourth side electrical connection portion 113d are provided on the third side surface and the fourth side surface adjacent to the first side surface, respectively, of the piezoelectric vibrator 11, so that the piezoelectric vibrator 11 of the piezoelectric actuator 10 can be electrically conducted from the side surface of the piezoelectric vibrator 11 to an external device. Specifically, the first side electrical connection portion 113a is formed on the third side surface of the piezoelectric vibrator 11 and is electrically connected to the at least one first electrode layer 112 a; the second side electrical connection portion 113b is formed on the third side surface of the piezoelectric vibrator 11 and is electrically connected to the at least one second electrode layer 112 b; the third side electrical connection portion 113c is formed on the fourth side surface of the piezoelectric vibrator 11 and is electrically connected to the at least one third electrode layer 112 c; the fourth side electrical connection portion 113d is formed on the fourth side surface of the piezoelectric vibrator 11 and is electrically connected to the at least one fourth electrode layer 112 d.

With the above arrangement of the multilayer electrode layers 112, it is also possible to polarize the multilayer ceramic layers 111 arranged between the multilayer electrode layers 112 by supplying power to the multilayer electrode layers 112. In one specific example, the third side electrical connection portion 113c is connected to a positive power supply voltage, and the fourth side electrical connection portion 113d is connected to a negative power supply voltage, so as to provide a positive voltage to at least one third electrode layer 112c and a negative voltage to at least one fourth electrode layer 112d, respectively, to polarize the multilayer ceramic layer 111 disposed between the multilayer electrodes. The piezoelectric ceramics are polarized, and then are automatically polarized in a direction arrangement to form a piezoelectric, and the piezoelectric vibrator 11 is polarized by the above specific example, and a schematic polarization diagram is shown in fig. 7. It is to be noted that the size ratio and the number of layers of the piezoelectric vibrator 11 are exaggerated in order to clearly illustrate the polarization of the piezoelectric vibrator 11.

After the completion of the polarization, different electric signals are respectively supplied to vibrate the piezoelectric vibrator 11 driving the piezoelectric actuator 10 in the first bending mode or the second bending mode. Specifically, the third side electrical connection portion 113c is connected to the ground line to connect at least one third electrode layer 112c to the ground line, the fourth side electrical connection portion 113d is connected to the ground line to connect at least one fourth electrode layer 112d to the ground line, the first side electrical connection portion 113a is connected to the first signal to connect at least one first electrode layer 112a to the first signal, and the second side electrical connection portion 113b is connected to the second signal to connect at least one second electrode layer 112b to the second signal, wherein the first signal and the second signal are the same and are sine wave or rectangular wave signals with the frequency F1, so that the piezoelectric vibrator 11 is bending vibrated in the first bending mode, and the piezoelectric actuator 10 can drive the driven object to move in the first direction at the first speed V1; the third side electrical connection portion 113c is connected to the ground line to connect at least one third electrode layer 112c to the ground line, the fourth side electrical connection portion 113d is connected to the ground line to connect at least one fourth electrode layer 112d to the ground line, the first side electrical connection portion 113a is connected to the third signal to connect at least one first electrode layer 112a to the third signal, and the second side electrical connection portion 113b is connected to the fourth signal to connect at least one second electrode layer 112b to the fourth signal, wherein the third signal and the fourth signal are sine wave or rectangular wave signals having a frequency F2 and a phase difference of 180 °, in other words, the fourth signal and the third signal are equal in frequency, and the phase difference between the fourth signal and the third signal is 180 °, so that the piezoelectric vibrator 11 is bending-vibrated in the second bending mode, and the piezoelectric actuator 10 can drive the driven object to move in the second direction at the second speed V2. In a specific example, the frequency F1 of the first signal and the second signal is 225kHz, and the frequency F2 of the third signal and the fourth signal is 463kHz, i.e. the frequency of the electrical signal required for bending vibration of the piezoelectric vibrator 11 in the second bending mode is greater than the frequency of the electrical signal required for bending vibration of the piezoelectric vibrator 11 in the first bending mode.

Further, in the present application, the speed at which the piezoelectric actuator 10 drives the driven object to move in the first direction is greater than the speed at which the piezoelectric actuator 10 drives the driven object to move in the second direction, that is, the first speed V1 is greater than the second speed V2. In the first bending mode, the vibration frequency of the piezoelectric vibrator 11 is low but the vibration amplitude is large, so that the driving step length of the friction driving section 12 of the piezoelectric actuator 10 is longer but the driving frequency is low; in the second bending mode, the vibration frequency of the piezoelectric vibrator 11 is high but the vibration amplitude is small, so that the driving step of the friction driving portion 12 of the piezoelectric actuator 10 is short but the driving frequency is higher, and therefore, the speed at which the piezoelectric actuator 10 drives the driven object to move in two opposite directions is made different. In the present application, however, the amplitude of the piezoelectric vibrator 11 has a larger influence on the driving speed of the piezoelectric actuator 10 than the vibration frequency of the piezoelectric vibrator 11. For example, in one example, the amplitude of the piezoelectric vibrator 11 in the first bending mode is more than five times larger than the amplitude of the piezoelectric vibrator 11 in the second bending mode, and the vibration frequency of the piezoelectric vibrator 11 in the first bending mode is about half of the vibration frequency of the piezoelectric vibrator 11 in the second bending mode. Therefore, the first speed V1 at which the piezoelectric actuator 10 drives the driven object to move in the first direction is made greater than the second speed V2 at which the piezoelectric actuator 10 drives the driven object to move in the second direction.

Exemplary drive Motor group

The present application further provides a drive motor assembly 20, as shown in fig. 8, the drive motor assembly 20 employing a piezoelectric actuator 10 as illustrated in fig. 1-7, adapted to provide two linear drives of opposite direction and unequal speed.

As shown in fig. 8, the driving motor group 20 includes a piezoelectric actuator 10, a stator 21, a mover 22, and a pre-compression member 324, wherein the piezoelectric actuator 10 is frictionally coupled to the mover 22 through the pre-compression member 324 and configured to drive the mover 22 to move in a length direction, and the piezoelectric actuator 10 can drive the mover 22 to move in two opposite directions at different speeds, respectively. Precompression member 324 provides compressive force of piezoelectric actuator 10 toward mover 22 to maintain friction drive portion 12 of piezoelectric actuator 10 in contact with mover 22.

In one example, the piezoelectric actuator 10 is fixed to the stator 21 by the pre-compression member 324, and the pre-compression member 324 may be a spring plate, which is fixed to the piezoelectric actuator 10 and the stator 21, respectively. The piezoelectric actuator 10 is in frictional contact with the mover 22 by the frictional driving section 12, and the mover 22 moves in the longitudinal direction of the piezoelectric actuator 10 by frictional force. In the present application, the friction driving unit 12 of the piezoelectric actuator 10 used for driving the motor group 20 is eccentrically provided on the piezoelectric vibrator 11 of the piezoelectric actuator 10, and the moving speed of the driving mover 22 in the eccentric direction of the friction driving unit 12 by the piezoelectric actuator 10 is greater than the moving speed of the driving mover 22 in the opposite direction of the eccentric direction of the friction driving unit 12.

Exemplary camera Module

Fig. 9 to 13 illustrate a driving device 32 and an image capturing module 30 according to an embodiment of the present application, where the image capturing module 30 includes a photosensitive assembly 33, an optical lens 31 held on a photosensitive path of the photosensitive assembly 33, and a driving device 32 for driving the optical lens 31 to move to achieve optical performance adjustment, for example, to achieve anti-shake, focusing, and other functions.

Accordingly, the optical lens 31 includes a barrel and a plurality of optical lenses mounted on the barrel, the optical lens 31 has an optical axis, the optical axis of the optical lens 31 is also the optical axes of the plurality of optical lenses, and the photosensitive assembly 33 is disposed opposite to the optical lens 31 along the optical axis direction. For convenience of description, a side of the image capturing module 30 facing the object is taken as an object side, a side of the image capturing module 30 facing the photosensitive element 33 is taken as an image side, the optical axis direction includes a direction along the optical axis pointing to the image side (abbreviated as image side in the present application), and a direction along the optical axis pointing to the object side (abbreviated as object side in the present application), the horizontal direction is a direction perpendicular to the optical axis direction, and the height direction is a direction along the optical axis direction.

With continued reference to fig. 12, the optical lens 31 is fixed in the driving device 32, the photosensitive assembly 33 is fixed on the image side of the driving device 32, and further the optical lens 31 can be held on the photosensitive path of the photosensitive assembly 33 by the driving device 32, and the optical lens 31 is suitable for being driven by the driving device 32 to realize functions of anti-shake, focusing, and the like.

The photosensitive assembly 33 includes a chip circuit board 332, a photosensitive chip 331 and a plurality of electronic components 333 electrically connected to the chip circuit board 332, wherein the photosensitive chip 331 is used for receiving the external light collected by the optical lens 31 for imaging and electrically connected to an external mobile electronic device through the chip circuit board 332. In one embodiment of the present application, the plurality of electronic components 333 may be one or more of passive electronic devices such as resistors, capacitors, etc. and active electronic devices such as driver chips, memory chips, etc.

The photosensitive assembly 33 further includes a filter assembly 334, the filter assembly 334 includes a filter element 3341, the filter element 3341 is maintained on the photosensitive path of the photosensitive chip 331, and the filter element 3341 is disposed between the optical lens 31 and the photosensitive chip 331 and is used for filtering incident light entering the photosensitive chip 331 to remove stray light, such as infrared light, of the incident light, which is not required for imaging.

The filter assembly 334 further includes a filter element support 3342, the filter element 3341 is mounted and fixed on the filter element support 3342 and corresponds to at least the photosensitive region of the photosensitive chip 331, the filter element support 3342 has a light-passing hole, and the incident light passing through the optical lens 31 is incident on the photosensitive chip 331 through the light-passing hole, and the filter element 3341 can be attached to the filter element support 3342.

Further, the filter element support 3342 is fixed to the chip circuit board 332, and in one embodiment of the present application, the photosensitive assembly 33 is fixed to the image side of the driving device 32 through the filter element support 3342, and in another embodiment of the present application, the photosensitive assembly 33 may also be fixed to the image side of the driving device 32 through the chip circuit board 332.

The filter element support 3342 may be fixed to the chip circuit board 332 by, for example, bonding with an adhesive medium after being preformed, or may be integrally formed with the chip circuit board 332 by, for example, molding, and directly fixed to the chip circuit board 332 by integral molding.

Exemplary drive apparatus

The present application proposes a novel driving device 32, which not only has relatively larger driving force and better driving performance (specifically including higher-precision driving control and longer driving stroke), but also has the advantages of small size, low power consumption and the like so as to be suitable for the development trend of the current camera module for light weight and thin type.

In particular, the novel driving device 32 is a piezoelectric actuator with a novel structure, and the piezoelectric actuator can meet the technical requirements of the camera module 30 on the driver. And, the piezoelectric actuator is further arranged in the camera module 30 in a proper arrangement manner to drive the optical lens 31 for position adjustment, so that the piezoelectric actuator meets the structural design requirement and the dimensional design requirement of the camera module 30.

In one embodiment of the present application, the driving device 32 drives the optical lens 31 to move along the optical axis, or to move along the height direction of the driving device 32, so as to adjust the distance between the optical lens 31 and the photosensitive assembly 33, so as to implement the focusing function. In another embodiment of the present application, the driving device 32 drives the optical lens 31 to move along a plane perpendicular to the optical axis direction, so that the optical lens 31 moves in a horizontal direction relative to the photosensitive assembly 33 to realize the anti-shake function.

With continued reference to fig. 9-13, in one embodiment of the present application, the driving device 32 includes a fixed portion 321, a movable portion 322, a driving portion 323, a pre-compression member 324, and a guiding device 325. Wherein the movable portion 322, the driving portion 323, the pre-compression member 324 and the supporting device are accommodated in the fixed portion 321, the optical lens 31 is disposed in the movable portion 322, the driving portion 323 is disposed between the movable portion 322 and the fixed portion 321 to drive the movable portion 322 to move relative to the fixed portion 321, the pre-compression member 324 is disposed between the driving portion 323 and the fixed portion 321 so that the movable portion 322 and the driving portion 323 always maintain frictional contact, and the guiding device 325 is disposed between the movable portion 322 and the fixed portion 321 to provide guiding for movement of the movable portion 322. The driving device 32 includes an object side, an image side, and a peripheral side between the object side and the image side, and the peripheral side includes a first side, a second side, a third side, and a fourth side sequentially disposed around the optical axis.

Particularly, in the embodiment of the present application, the optical lens 31 is mounted on the movable portion 322 in a linkage manner, the photosensitive assembly 33 is mounted on the fixed portion 321 in a fixed manner, and when the optical focusing function of the image capturing module 30 is achieved, the driving portion 323 drives the optical lens 31 to move along the optical axis direction (or the height direction) so as to adjust the distance between the optical lens 31 and the photosensitive assembly 33, so that the light from the object passes through the optical lens 31 and reaches the photosensitive chip 331 of the photosensitive assembly 33, thereby achieving clear imaging.

Specifically, referring to fig. 11, in the embodiment of the present application, the fixing portion 321 includes a base 3212 and an upper cover 3211 fastened to the base 3212, where the base 3212 and the upper cover 3211 form a receiving cavity for receiving the movable portion 322, the driving portion 323, the pre-pressing member 324 and the supporting device therein, so that not only the components in the driving device 32 can be protected from being damaged due to impact, but also dust, dirt or stray light can be prevented from entering the driving device 32.

The upper cover 3211 includes an upper cover top portion 32111 and an upper cover side wall 32112 integrally extending in the direction of the base 3212, and is fixed to the base 3212 by the upper cover side wall 32112, for example, by laser welding or adhesive bonding. Further, the top cover top portion 32111 and the base 3212 are each provided with an opening corresponding to the optical lens 31, so that light reflected by the object can pass through the optical lens 31 to reach the photosensitive assembly 33.

Specifically, the fixed portion 321 is a stator, the movable portion 322 is a mover, the movable portion 322 is suspended in the accommodating cavity of the fixed portion 321, and the movable portion 322 can move along the optical axis direction (or the height direction) relative to the fixed portion 321 under the driving of the driving portion 323, so as to implement the optical focusing function of the camera module 30.

In the embodiment of the present application, with continued reference to fig. 9 to 13, the movable portion 322 includes a movable carrier 3221 and a friction plate 3222, and the optical lens 31 is disposed on the movable carrier 3221, wherein the manner in which the optical lens 31 is disposed on the movable carrier 3221 includes, but is not limited to, adhesion, threading, engagement, and the like. The movable carrier 3221 includes carrier side walls 32211 disposed in order along a circumferential side thereof, and in a specific example of the present application, the number of carrier side walls 32211 is 4, namely, a first carrier side wall 322111, a second carrier side wall 322112, a third carrier side wall 322113, and a fourth carrier side wall 322114, as shown in fig. 13. Wherein the first carrier sidewall 322111 is on a first side, the second carrier sidewall 322112 is on a second side, the third carrier sidewall 322113 is on a third side, and the fourth carrier sidewall 322114 is on a fourth side.

In another specific example of the present application, a first cut edge 32211a is provided at the corner of the first carrier side wall 322111 and the second carrier side wall 322112 of the movable carrier 3221, a second cut edge 32211b is provided at the corner of the second carrier side wall 322112 and the third carrier side wall 322113 of the movable carrier 3221, a third cut edge 32211c is provided at the corner of the third carrier side wall 322113 and the fourth carrier side wall 322114 of the movable carrier 3221, and a fourth cut edge 32211d is provided at the corner of the fourth carrier side wall 322114 and the first carrier side wall 322111 of the movable carrier 3221, that is, the number of carrier side walls 32211 of the movable carrier 3221 is 8, as shown in fig. 10.

The friction plate 3222 is provided on the carrier side wall 32211 of the movable carrier 3221, for example, the friction plate 3222 is integrally formed on the carrier side wall 32211, but of course, the friction plate 3222 and the carrier side wall 32211 may be separate structures, that is, the friction plate 3222 and the carrier side wall 32211 are separate members, and are attached to the carrier side wall 32211 by an adhesive. In a specific example of the present application, the friction plate 3222 may be provided to the first cutout 32211a; in another specific example of the present application, the friction plate 3222 may be disposed on the first carrier sidewall 322111.

Further, a friction plate 3222 is provided on a side of the carrier side wall 32211 facing the driving portion 323, that is, the friction plate 3222 is sandwiched between the movable portion 322 and the driving portion 323, so that the driving portion 323 is frictionally coupled to the friction plate 3222 by the action of the pre-pressing member 324. It should be understood that the friction plate 3222 functions to increase friction between the movable portion 322 and the movable portion 322. The friction plate 3222 may be a metal oxide material such as an oxidized pick or aluminum oxide.

In the embodiment of the present application, the driving portion 323 is disposed between the movable portion 322 and the fixed portion 321, and the driving portion 323 is fixed to the fixed portion 321 and is in frictional contact with the movable portion 322, so as to drive the movable portion 322 to move in the optical axis direction (height direction) to realize the optical focusing function. The driving part 323 is disposed at a peripheral side of the driving device 32 to avoid increasing the height of the driving device 32.

It should be understood that, in the technical solution of the present application, the driving portion 323 employs the piezoelectric actuator as described above, wherein the driving portion 323 includes the piezoelectric vibrator 11 and the friction driving portion 12, and the friction driving portion 12 is fixed to the piezoelectric vibrator 11, so that the friction driving portion 12 changes the positional information along with the deformation of the piezoelectric vibrator 11. In one embodiment of the present application, the driving part 323 drives the movable part 322 to move in the first direction or the second direction, wherein the first direction is opposite to the second direction, and the speed of the driving part 323 driving the movable part 322 to move in the first direction is greater than the speed of the driving part 323 driving the movable part 322 to move in the second direction. The first direction and the second direction are the same as the height direction, for example, the first direction is toward the object side, and the second direction is toward the image side.

Specifically, the driving portion 323 is disposed between the fixed portion 321 and the movable portion 322, the piezoelectric vibrator 11 is fixed to the fixed portion 321 by the pre-compression member 324, the friction driving portion 12 faces the movable portion 322, the friction plate 3222 is sandwiched between the movable carrier 3221 and the friction driving portion 12, and the friction driving portion 12 is frictionally coupled to the friction plate 3222. The friction driving part 12 moves by the driving of the piezoelectric vibrator 11, so that the driving part 323 can drive the movement of the movable part 322 by the friction force between the friction driving part 12 and the friction plate 3222.

As can be seen from the foregoing, the piezoelectric vibrator 11 has a rectangular or nearly rectangular structure, the length direction of the piezoelectric vibrator 11 is the height direction of the driving device 32, and when the driving portion 323 is energized by the power supply, the piezoelectric vibrator 11 generates a plane change along the length direction, so as to drive the friction driving portion 12 to reciprocate along the height direction, and the friction driving portion 12 and the friction plate 3222 are brought into frictional contact with each other, so as to drive the friction plate 3222 and the movable carrier 3221 to move along the optical axis direction.

More specifically, the friction drive portion 12 is provided eccentrically on the piezoelectric vibrator 11 in the longitudinal direction of the piezoelectric vibrator 11, and the friction drive portion 12 is provided eccentrically on the piezoelectric vibrator 11 in the height direction of the drive device 32. In one embodiment of the present application, the friction driving portion 12 is disposed near the top of the piezoelectric vibrator 11 in the height direction, that is, the distance from the contact point of the friction driving portion 12 and the friction plate 3222 to the top end of the piezoelectric vibrator 11 is smaller than the distance from the contact point of the friction driving portion 12 and the friction plate 3222 to the bottom end of the piezoelectric vibrator 11. Of course, the distance from the friction driving portion 12 to the top end of the piezoelectric vibrator 11 is smaller than the distance from the friction driving portion 12 to the bottom end of the piezoelectric vibrator 11 in the height direction.

It should be understood that the piezoelectric vibrator 11 of the driving portion 323 in the present application has two bending modes: a first bending mode and a second bending mode, the first bending mode and the second bending mode being implemented by inputting circuit signals of different frequencies. The piezoelectric vibrator 11 vibrates in two bending modes, so that the eccentrically disposed friction driving portions 12 are respectively driven to make elliptical motions in two directions, and the driving portions respectively drive the movable portions 322 to move in two opposite directions, i.e., a first direction or a second direction, in the two bending modes.

In the first bending mode, the piezoelectric vibrator 11 is bending-vibrated in the form of one peak or trough in the thickness direction thereof, so that the friction driving portion 12 eccentrically fixed to the piezoelectric vibrator 11 can drive the movable portion 322 to move in the first direction; in this second bending mode, the piezoelectric vibrator 11 is bending-vibrated in the form of one peak and one trough in the thickness direction thereof, so that the friction driving portion 12 eccentrically fixed to the piezoelectric vibrator 11 can drive the movable portion 322 to move in the second direction.

Further, in the first bending mode, the piezoelectric vibrator 11 has the maximum amplitude at only one point in the bending state, the piezoelectric vibrator 11 is in symmetrical bending vibration, and the movable portion 322 is driven to move in the eccentric direction (first direction) of the friction driving portion 12 by the eccentrically arranged friction driving portion 12, that is, the movable portion 322 is driven by the friction driving portion 12 to move in the object side direction; in the second bending mode, the piezoelectric vibrator 11 has the maximum amplitude at only two positions in the bending state, the piezoelectric vibrator 11 is rotationally symmetric to perform bending vibration, and the friction driving portion 12 is disposed between the peak and the trough of the piezoelectric vibrator 11 in the second bending mode, so that the movable portion 322 is driven to move in the opposite direction (second direction) of the eccentric direction of the friction driving portion 12 by the eccentrically disposed friction driving portion 12, that is, the movable portion 322 is driven by the friction driving portion 12 to move in the image side direction.

In the solution of the present application, the speed at which the movable part 322 is driven to move in the first direction is greater than the speed at which it is driven to move in the second direction, i.e., the first speed V1 is greater than the second speed V2. In the first bending mode, the vibration frequency of the piezoelectric vibrator 11 is low but the vibration amplitude is large, so that the driving step length of the friction driving portion 12 of the driving portion 323 is longer but the driving frequency is low; in the second bending mode, the vibration frequency of the piezoelectric vibrator 11 is high but the vibration amplitude is small, so that the driving step of the friction driving portion 12 of the driving portion 323 is short but the driving frequency is higher, and therefore, the driving portion 323 is made to drive the movable portion 322 in two opposite directions at different speeds.

In the initial state, the optical lens 31 is closer to the image side, and the focal point of the optical lens 31 falls behind the image plane of the photosensitive chip 331. When the optical focusing is performed, the optical lens 31 may be moved toward the object side by the driving part 323, so that the focal point of the optical lens 31 falls on the image plane of the photosensitive chip 331. In this process, first, the driving part 323 drives the movable part 322 to further drive the optical lens 31 to move along the first direction to reach the first position, wherein the object can be blurred imaged on the photosensitive chip 331 at the first position; then, the driving portion 323 drives the movable portion 322 to further drive the optical lens 31 to move along the first direction or the second direction to reach the second position, wherein the object can be clearly imaged on the photosensitive chip 331 at the second position. It should be appreciated that, since the optical lens 31 is moved farther in the first direction, the optical lens 31 is driven to move faster in the first direction, so that the optical lens 31 can be quickly moved to the focusing position, thereby achieving quick focusing.

It should be understood that the distance from the friction drive portion 12 to the top end of the friction plate 3222 is smaller than the distance from the friction drive portion 12 to the bottom end of the friction plate 3222 in the height direction. Since the optical lens 31 moves farther in the first direction, the distance from the friction drive portion 12 to the bottom of the friction plate 3222 needs to be longer so that the friction drive portion 12 can always maintain frictional contact with the friction plate 3222 when the friction plate 3222 is driven to move in the first direction. It can be said that the distance from the friction driving portion 12 to the bottom end of the friction plate 3222 is equal to or greater than the movement stroke of the movable carrier 3221, so that the friction driving portion 12 is not separated from the friction plate 3222 due to insufficient length of the friction plate 3222 in the process of moving the movable carrier 3221, and further the driving effect is not affected.

More specifically, in one embodiment of the present application, the driving portion 323 drives the movable portion 322 to further drive the optical lens 31 to move along the first direction to reach the first position, wherein the distance from the first position to the photosensitive chip 331 is greater than the focal length of the optical lens 31; then, the driving portion 323 drives the movable portion 322 to further drive the optical lens 31 to move along the second direction to reach a second position, wherein a distance from the second position to the photosensitive chip 331 is equal to a focal length of the optical lens 31, so that a focal point of the optical lens 31 falls on an image plane of the photosensitive chip 331.

In another embodiment of the present application, the driving portion 323 drives the movable portion 322 to further drive the optical lens 31 to move along the first direction to reach the first position, wherein the distance from the first position to the photosensitive chip 331 is smaller than the focal length of the optical lens 31; then, the driving portion 323 drives the movable portion 322 to further drive the optical lens 31 to move along the first direction to reach a second position, wherein a distance from the second position to the photosensitive chip 331 is equal to a focal length of the optical lens 31, so that a focal point of the optical lens 31 falls on an image plane of the photosensitive chip 331.

Of course, in the technical solution of the present application, after the optical lens 31 reaches the first position, the optical lens 31 may be moved along the first direction or along the second direction multiple times, so as to reach the second position, the third position, the fourth position, etc., until the focal point of the optical lens 31 falls on the image plane of the photosensitive chip 331, so that the photosensitive chip 331 may clearly image.

In the present embodiment, it is generally necessary to configure the pre-pressing member 324 to provide pre-pressing force between the driving part 323 and the movable part 322 by the pre-pressing member 324, so that the friction driving part 12 of the driving part 323 is frictionally coupled to the friction plate 3222 of the movable part 322 under the pre-pressing force to drive the movable part 322 to move in the driving direction by the friction force.

The pre-compression member 324 is disposed between the driving portion 323 and the fixed portion 321, and the pre-compression generated by the pre-compression member 324 maintains frictional contact between the friction driving portion 12 and the friction plate 3222 at all times. Wherein, the pre-pressure part 324 includes two fixed ends 3241 and a connection section 3242 integrally connected between the two fixed ends 3241. The two fixed ends 3241 of the pre-pressure member 324 are fixed to the upper cover 3211 of the fixed portion 321, the piezoelectric vibrator 11 of the driving portion 323 is disposed at the connecting section 3242 of the pre-pressure member 324, and the pre-pressure member 324 generates pre-pressure toward the movable portion 322, so that friction contact is always maintained between the friction driving portion 12 of the driving portion 323 and the friction plate 3222 of the movable carrier 3221.

Further, the inner side surface of the upper cover sidewall 32112 is provided with the fixing position 321122 of the pre-pressing member 324, and the two fixing ends 3241 of the pre-pressing member 324 can be disposed on the fixing position 321122 of the pre-pressing member 324, so that the pre-pressing member 324 is convenient to install, and the structure of the driving device 32 is more stable.

Since the connection section 3242 is in contact with the piezoelectric vibrator 11, when the piezoelectric vibrator 11 is deformed in a plane, the connection section 3242 of the pre-pressure member 324 is deformed. Accordingly, a space is reserved between the connecting section 3242 and the inner side of the upper cover sidewall 32112 to provide a sufficient spatial location for deformation of the precompression member 324. It can be said that a certain gap is provided between the connection section 3242 and the fixing portion 321, and the piezoelectric vibrator 11 is provided on a side of the connection section 3242 away from the fixing portion 321, that is, on a side of the connection section 3242 of the pre-pressing member 324 away from the piezoelectric vibrator 11, without being in contact with an inner side surface of the upper cover side wall 32112.

It should be appreciated that in one embodiment of the present application, the pre-compression component 324 may be implemented as a dome; in another embodiment of the present application, the pre-compression member 324 may be implemented as an adhesive having elasticity.

In order to improve the stability of the camera module 30 in the optical focusing process and improve the imaging quality, the guide device 325 is arranged between the upper cover 3211 and the movable part 322, and the guide device 325 can always support the movable carrier 3221 in the optical focusing process so as to enable the movable carrier to stably move; the guide 325 may also provide a guide for movement of the movable portion 322.

Specifically, the inner side surface of the upper cover side wall 32112 of the upper cover 3211 is provided with a first guide groove 321121, the first guide groove 321121 extends in the height direction, the outer side surface of the carrier side wall 32211 of the movable carrier 3221 is provided with a second guide groove 32212, and the second guide groove 32212 extends in the height direction. The first guide groove 321121 and the second guide groove 32212 are oppositely arranged, the guide device 325 is clamped between the first guide groove 321121 and the second guide groove 32212, the guide device 325 can avoid direct contact between the movable carrier 3221 and the upper cover 3211, and friction force generated by the movable carrier 3221 in the moving process is reduced. Further, the guide 325 is disposed in the first guide groove 321121 and the second guide groove 32212, the movement track of the guide 325 is limited to the first guide groove 321121 and the second guide groove 32212, and the guide 325 moves in the height direction in the first guide groove 321121 and the second guide groove 32212, thereby providing a guide for the movement of the movable carrier 3221.

In one embodiment of the present application, the first guide groove 321121 can include two sub-guide grooves, a first sub-guide groove and a second sub-guide groove; the second guide groove 32212 may include two sub-guide grooves, a third sub-guide groove and a fourth sub-guide groove. Wherein, the two sub-guide grooves of the first guide groove 321121 are opposite to the two sub-guide grooves of the second guide groove 32212, the number of the guide devices 325 is two, and the two guide devices 325 are respectively clamped in the two opposite sub-guide grooves. It should be understood that the first sub-guide groove and the second sub-guide groove are symmetrically disposed at the inner side surface of the upper cover sidewall 32112, and the third sub-guide groove and the fourth sub-guide groove are symmetrically disposed at the outer side surface of the carrier sidewall 32211 of the movable carrier 3221, so that the movable carrier 3221 can be maintained stationary during movement without tilting.

As shown in fig. 10, in one embodiment of the present application, the pre-pressing member 324, the driving portion 323, and the guide 325 are provided on the cut edge of the movable carrier 3221, in conformity with the structure of the movable carrier 3221. The arrangement can fully utilize the free space at the corners of the driving device 32, so that the driving device 32 has a more compact structure, and the size of the driving device 32 is reduced. Specifically, the driving portion 323 is provided on a first tangential side of the movable carrier 3221, and the pre-pressing member 324 is fixed to the upper cover 3211 and abuts against the piezoelectric vibrator 11 of the driving portion 323 so that the friction driving portion 12 of the driving portion 323 is in friction contact with the first tangential side of the movable carrier 3221. Of course, the first trimming of the movable carrier 3221 may be provided with the friction plate 3222 so that frictional contact is maintained between the friction drive portion 12 and the friction plate 3222.

The two sub-guide grooves of the second guide groove 32212 are provided in the second cut edge and the third cut edge of the movable carrier 3221, and the two sub-guide grooves of the first guide groove 321121 are provided opposite to the upper cover side wall 32112. In a specific embodiment, the second and third trimmings of the movable carrier 3221 have inwardly extending grooves, in which the first and second sub-guide grooves are disposed, and the upper cover side wall 32112 has inwardly extending protrusion structures, on which the third and fourth sub-guide grooves are disposed, and of course, the grooves of the second and third trimmings of the movable carrier 3221 are disposed opposite to the protrusion structures of the upper cover side wall 32112, so that the guide device 325 can be clamped between the first and second guide grooves 321121 and 32212.

Further, when the first sub-guide groove is disposed opposite to the third sub-guide groove to sandwich the guide device 325, the opening directions of the first sub-guide groove and the third sub-guide groove are opposite; when the second sub-guide groove is disposed opposite to the fourth sub-guide groove to sandwich the guide 325, the opening directions of the second sub-guide groove and the fourth sub-guide groove are opposite. The arrangement may be such that a space is formed between the first sub-guide slot and the third sub-guide slot to accommodate the guide device 325, and a space is formed between the second sub-guide slot and the fourth sub-guide slot to accommodate the guide device 325. It should be understood that the opening directions of the first sub-guide groove and the second sub-guide groove may be the same or different, and the opening directions of the third sub-guide groove and the fourth sub-guide groove may be the same or different, which is not limited in this application.

Along the optical axis direction, the two guiding devices 325 are symmetrically arranged relative to the center line of the friction driving portion 12, and since the piezoelectric vibrator 11 deforms in the movement stroke, the friction driving portion 12 generates an elliptical track-shaped two-dimensional track along with the deformation of the piezoelectric vibrator 11, so that the friction driving portion 12 generates a tilting moment applied to the friction plate 3222 of the movable carrier 3221 in the movement track, and the symmetrically arranged guiding devices 325 can disperse the tilting moment, so that the structure of the movable carrier 3221 is more stable.

As shown in fig. 13, in another embodiment of the present application, the guiding device 325 and the pre-compression member 324 are disposed on opposite sides of the movable carrier 3221, for example, when the pre-compression member 324 is disposed on the first carrier sidewall 322111 of the movable carrier 3221, the guiding device 325 is disposed on the fourth carrier sidewall 322114 opposite thereto. The pre-pressing member 324 generates a pre-pressing force in the horizontal direction toward the guide device 325, and the pre-pressing force can not only always maintain frictional contact between the friction drive section 12 and the movable carrier 3221, but also always hold the guide device 325 between the upper cover 3211 and the movable carrier 3221.

The movable carrier 3221 is sandwiched between the guide 325 and the driving portion 323, and the driving portion 323 and the movable carrier 3221 are sandwiched between the pre-compression member 324 and the guide 325, that is, the movable carrier 3221 is suspended in the upper cover 3211 by the guide 325 and the pre-compression member 324. This arrangement makes the structure of the driving device 32 more compact and the arrangement of the positions of the respective components more reasonable.

It should be understood that the guide 325 may be implemented as balls, in a specific example of the present application, the number of balls is four, which are respectively sandwiched between two sub-guide grooves of the first guide groove 321121 and two sub-guide grooves of the second guide groove 32212, and two balls are provided between each two sub-guide grooves, so that the movable carrier 3221 can be kept stable. In another specific example of the present application, the number of balls is six, three balls are disposed between every two sub-guide grooves, and the three balls are stacked in the height direction. In particular, two balls located on the upper side and the lower side of the three balls have diameters larger than those of the balls located in the middle position so as to avoid interference during movement. Of course, the guide 325 may also be implemented as a slider or a guide bar, which is not limited in this application.

Further, in the embodiment of the present application, the driving device 32 further includes an electrical connection portion 326, where the electrical connection portion 326 is disposed between the pre-pressing member 324 and the upper cover sidewall 32112 for electrically connecting the piezoelectric vibrator 11 of the driving portion 323 to achieve the electrical conduction of the driving device 32. Of course, the electrical connection portion 326 may be directly electrically connected to the motherboard of the electronic device, or may extend to the photosensitive assembly 33 to be electrically connected to the chip circuit board 332, which is not limited in this application.

It should be understood that in the embodiment of the present application, the driving device 32 further includes a position sensing portion 327, where the position sensing portion 327 includes a position sensing element 3271 and a position sensing magnet 3272, where the position sensing element 3271 is disposed on one of the movable carrier 3221 and the upper cover 3211, the position sensing magnet 3272 is disposed on the other of the movable carrier 3221 and the upper cover 3211, and the position sensing element 3271 and the position sensing magnet 3272 are disposed opposite to each other. When the movable carrier 3221 is driven to move, the relative position between the position sensing element 3271 and the position sensing magnet 3272 changes, and the position of the movable carrier 3221 can be determined based on the strength of the magnetic field of the position sensing magnet 3272 sensed by the position sensing element 3271, and the excitation voltage of the piezoelectric vibrator 11 can be adjusted so that the movable carrier 3221 moves to a desired position.

In a specific example of the present application, the position sensing element 3271 is disposed on the upper cover sidewall 32112 to enable the circuit conduction of the position sensing portion 327 through the electrical connection portion 326 disposed on the upper cover sidewall 32112, so as to simplify the conductive structure of the driving device 32. In this application, the position sensing element 3271 may be a hall element, a driver IC, or a TMR.

Of course, in an embodiment of the present application, the position sensing portion 327 may be disposed on the third trimming of the movable carrier 3221, so that the structure of the driving device 32 is more compact, and thus the structure of the driving device 32 is more stable. Of course, the position sensing portion 327 may be disposed at other positions of the driving device 32, for example, the position sensing portion 327 is disposed on the second carrier sidewall 322112, which is not limited in the application per se.

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

Claims (10)

1. A driving device, characterized by comprising:

a fixing part;

a movable portion movably provided in the fixed portion; and

and a driving part arranged between the fixed part and the movable part, wherein the driving part drives the movable part to move along a first direction or a second direction, and the first direction is opposite to the second direction, and the speed of the driving part driving the movable part to move along the first direction is greater than the speed of the driving part driving the movable part to move along the second direction.

2. The driving device according to claim 1, wherein the driving portion includes a piezoelectric vibrator and a friction driving portion fixed to the piezoelectric vibrator, the friction driving portion being provided eccentrically on the piezoelectric vibrator in a height direction.

3. The driving device according to claim 2, wherein the piezoelectric vibrator includes two bending modes of a first bending mode and a second bending mode, and the driving portion drives the movable portion to move in the first direction or the second direction in the two bending modes, respectively.

4. The driving device according to claim 3, wherein a distance from the friction driving portion to the piezoelectric vibrator top end is smaller than a distance from the friction driving portion to the piezoelectric vibrator bottom end in a height direction.

5. The drive device of claim 4, wherein the movable portion includes a movable carrier and a friction plate sandwiched between the movable carrier and the friction drive portion, the friction drive portion being frictionally coupled to the friction plate.

6. The driving device according to claim 5, wherein a distance from the friction driving portion to the friction plate top end is smaller than a distance from the friction driving portion to the friction plate bottom end in a height direction.

7. The drive device according to claim 6, further comprising a pre-compression member provided between the fixed portion and the drive portion, the pre-compression member generating a pre-compression force such that frictional contact is always maintained between the friction drive portion and the friction plate.

8. The driving device according to claim 7, wherein the pre-pressure member includes two fixed ends fixed to the fixed portion and a connection section integrally connected between the two fixed ends with a certain gap therebetween, and the piezoelectric vibrator is provided at a side of the connection section away from the fixed portion.

9. The drive device according to claim 8, wherein the drive device further comprises a guide device provided between the fixed portion and the movable portion, the movable portion being sandwiched between the pre-compression member and the guide device.

10. A camera module, comprising:

an optical lens;

a photosensitive assembly, the optical lens being held on a photosensitive path of the photosensitive assembly; and

The driving device according to any one of claims 1 to 9, wherein the optical lens is mounted to the movable portion of the driving device.