CN116974033B - Actuating device, zoom lens and camera - Google Patents

Abstract

The invention discloses an actuating device, a zoom lens and a camera, which belong to the technical field of zoom lenses and comprise a transmission shaft, a transmission mechanism and a piezoelectric actuating system, wherein the transmission mechanism comprises a first fixed ring, a second fixed ring and a third fixed ring, the first fixed ring is fixedly connected to the transmission shaft, and a plurality of first branch bars are hinged between the first fixed ring and the second fixed ring; a plurality of second branch bars are hinged between the second fixing ring and the third fixing ring; the piezoelectric actuating system is used for driving the transmission shaft to rotate so as to drive the first branch strip to rotate relative to the first fixed ring and drive the second branch strip to rotate relative to the second fixed ring, so that the transmission mechanism is unfolded or folded along the axial direction of the transmission shaft. The actuating device of the invention occupies a smaller volume but can provide a larger moving stroke, and is suitable for lenses requiring a large zoom stroke and miniaturization.

Description

An actuating device, zoom lens and camera

Technical field

The invention belongs to the technical field of zoom lenses, and in particular relates to an actuating device, a zoom lens and a camera.

Background technique

The automatic zoom camera device requires the use of an actuator to move the position of the lens to change the focal length, so as to clearly capture objects at different distances. With the improvement of technology, the application scope of automatic zoom camera devices is getting wider and wider, such as mobile electronic devices such as mobile phones, tablet computers, micro robots, and unmanned reconnaissance aircraft. Correspondingly, the performance requirements for automatic zoom camera devices are also getting higher and higher. Come higher and higher.

There is a lens transmission device in the prior art (Chinese invention patent application, publication number CN101065957A). This prior art discloses the use of a screw structure to drive the movement of the lens barrel to achieve lens zoom. However, this design cannot take into account the zoom stroke. And the volume of the lens. For example, if you want to increase the zoom stroke of the lens, you need to increase the length of the screw. Due to the rigidity of the screw, the volume of the lens will inevitably increase. For example, if you want to reduce the volume of the lens, you need to reduce the zoom stroke of the lens. Therefore, this The design cannot meet the design requirements of large zoom range and miniaturized lenses, making it difficult to be applied to today's mobile electronic devices.

Therefore, the existing technology needs to be improved and developed.

Contents of the invention

The object of the present invention is to provide an actuating device, a zoom lens and a camera, which occupy a small volume but can provide a large movement stroke, and are suitable for lenses requiring a large zoom stroke and miniaturization.

In a first aspect, the present invention provides an actuating device applied to a zoom lens, including a transmission shaft, a transmission mechanism and a piezoelectric actuation system. The transmission shaft is fixedly connected to the transmission mechanism and is rotatably arranged on the piezoelectric actuator. On the actuation system, the transmission shaft can rotate around its own axis;

The transmission mechanism includes a first fixed ring, a second fixed ring and a third fixed ring. The outer diameter of the first fixed ring is smaller than the inner diameter of the second fixed ring and the first fixed ring is fixedly connected to the On the transmission shaft, a plurality of first support bars are hingedly connected between the first fixed ring and the second fixed ring. When the first support bars rotate relative to the first fixed ring, they can pull the second fixed ring. The ring is close to the first fixed ring or pushes the second fixed ring away from the first fixed ring; the outer diameter of the second fixed ring is smaller than the inner diameter of the third fixed ring, and the second fixed ring and A plurality of second support bars are hingedly connected between the third fixed rings. When the second support bars rotate relative to the second fixed ring, they can pull the third fixed ring close to the second fixed ring or push the second fixed ring. The third fixed ring is away from the second fixed ring;

The piezoelectric actuation system is used to drive the transmission shaft to rotate to drive the first support bar to rotate relative to the first fixed ring and to drive the second support bar to rotate relative to the second fixed ring, so that The transmission mechanism is unfolded or folded along the axial direction of the transmission shaft.

The actuating device provided by the invention has a transmission mechanism that can be unfolded and folded. When folded, the overall volume can be greatly reduced. When unfolded, it can extend a larger distance. When used in a lens, it can take into account both the zoom stroke and the volume, and can adapt to large-scale applications. Design requirements for zoom stroke and miniaturized lenses.

Further, the first support bar is hingedly connected to the first fixed ring and the second fixed ring through a ball joint; the second support bar is connected to the second fixed ring and the second fixed ring through a ball joint. Three fixed ring hinges;

When the transmission shaft rotates around its own axis, the first support bar and the second support bar rotate to make the second fixed ring and the third fixed ring synchronously approach or move away from the first fixed ring. .

The ball head hinge can make the movement of the first and second support bars smoother and more flexible, which is beneficial to the rapid expansion and contraction of the transmission mechanism.

Further, the first support bar is hinged to the first fixed ring and the second fixed ring through a flexible hinge; the second support bar is connected to the second fixed ring and the third fixed ring through a flexible hinge. Ring hinge.

The flexible hinge can make the movement of the first and second branches more sensitive, which is beneficial to improving control accuracy and achieving high-precision control.

Further, the first fixed ring, the second fixed ring, the third fixed ring, the first support bar and the second support bar are processed in one piece.

Further, the piezoelectric actuation system includes at least one stator made of piezoelectric material. The stator is provided with an arc surface, and the arc surface is provided with a protruding contact portion. The contact portion is connected to the stator. The peripheral surface of the transmission shaft is in contact; the stator is used to generate vibration when excited by an electrical signal to cause the corresponding contact portion to perform an elliptical movement to drive the transmission shaft to rotate around its own axis.

Further, the piezoelectric actuation system includes two stators, and the two stators are respectively:

The first stator is provided with a first arc surface, the first arc surface is provided with a protruding first contact portion, and the first contact portion is in contact with the peripheral surface of the transmission shaft. ;The first stator is used to generate vibration when excited by an electrical signal to cause the first contact portion to perform an elliptical movement;

a second stator, the second stator is provided with a second arc surface, the second arc surface is provided with a protruding second contact portion, and the second contact portion is in contact with the peripheral surface of the transmission shaft; The second arc surface and the first arc surface form a circle; the second stator is used to generate vibration when excited by an electrical signal to cause the second contact portion to perform an elliptical movement and cooperate with the first The elliptical movement of the contact portion drives the drive shaft to rotate about its own axis.

Only two stators are provided to control the rotation of the transmission shaft, simplifying the structure, reducing the overall weight, achieving a lighter effect, and reducing control difficulty.

Further, the first arc surface semi-encloses the transmission shaft in the circumferential direction of the transmission shaft and the first contact portion is in contact with the outer circumferential surface of the transmission shaft;

The second arcuate surface and the first arcuate surface completely surround the transmission shaft in the circumferential direction of the transmission shaft, and the second contact portion is in contact with the outer peripheral surface of the transmission shaft.

Further, the stator is provided with a first elastic element and a second elastic element, the first elastic element is located on the side of the stator where the arc surface is provided, and the second elastic element is located away from the stator. On one side of the first elastic element, the first elastic element and the second elastic element are all used to provide elastic force for the stator to keep the contact portion in contact with the peripheral surface of the transmission shaft.

In a second aspect, the present invention provides a zoom lens, applied to a camera, including the above-mentioned actuating device, a lens holder, a first lens barrel, a second lens barrel and a third lens barrel;

The stator of the piezoelectric actuation system is fixed in the lens holder through a first elastic element and a second elastic element;

The first lens barrel is fixedly connected to the lens mount, the first lens barrel is coaxial with the first fixed ring and surrounds the first fixed ring;

The second lens barrel is sleeved on the first lens barrel and surrounds the second fixing ring;

The third lens barrel is sleeved on the second lens barrel and surrounds the third fixing ring. The third lens barrel is fixedly connected to the third fixing ring and is away from one end of the second lens barrel. Lenses installed.

The use of this actuating device can realize the continuous movement of the lens barrel. As an actuating device, it can realize the stepless focusing function and power-off self-locking function of the lens barrel. It can not only realize the adjustment of various focal lengths within its stroke, but also adjust the lens barrel during the adjustment process. Then the power is turned off in time to keep the focal length unchanged and save power.

In a third aspect, the present invention provides a camera, including the above-mentioned zoom lens.

The use of this zoom lens can achieve the effects of fast focusing response, high focusing accuracy, silent operation, strong environmental adaptability, simple structure, strong scalability, long zoom stroke and fast zoom speed.

It can be seen from the above that the actuating device and transmission mechanism of the present invention can be completely folded when properly designed, so that the entire actuating device only occupies a very small space. At the same time, the transmission mechanism can also be extended to a larger distance and is used in lenses. Medium time, it is conducive to the compact design of the lens and can also maintain or increase the zoom range. It is suitable for various mobile electronic devices today that have requirements for zoom range and volume.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of embodiments of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and accompanying drawings.

Description of drawings

FIG. 1 is a partial structural cross-sectional view of a zoom lens provided by an embodiment of the present invention.

Figure 2 is an assembly diagram of the transmission shaft and transmission mechanism in the embodiment of the present invention.

Figure 3 is a schematic diagram of the integrated molding process of the transmission mechanism in the embodiment of the present invention.

Figure 4 is an exploded view of the first lens barrel, the second lens barrel and the third lens barrel in the embodiment of the present invention.

Figure 5 is a schematic diagram of two resonance modes generated by the stator in the embodiment of the present invention.

FIG. 6 is a schematic diagram of the movement direction of the first contact part when the first stator is excited to vibrate and cause the transmission shaft to rotate clockwise in the embodiment of the present invention.

7 is a schematic diagram of the movement direction of the second contact portion when the vibration of the second stator is excited to cause the transmission shaft to rotate counterclockwise in the embodiment of the present invention.

Explanation of labels: 100. Transmission shaft; 200. Piezoelectric actuation system; 210. First stator; 211. First arc surface; 212. First contact part; 220. Second stator; 221. Second arc surface; 222. The second contact part; 230. The first elastic element; 240. The second elastic element; 310. The first fixed ring; 320. The second fixed ring; 330. The third fixed ring; 340. The first support bar; 350 , second support bar; 400, lens holder; 500, first lens barrel; 600, second lens barrel; 700, third lens barrel; 710, lens.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and are not to be construed as limitations of the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " The directions indicated by "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" etc. or The positional relationship is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, Therefore, it should not be construed as a limitation of the present invention. In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, features defined as “first” and “second” may explicitly or implicitly include one or more of the described features. In the description of the present invention, "plurality" means two or more than two, unless otherwise explicitly and specifically limited.

In the description of the present invention, it should be noted that, unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection. Connection, or integral connection; it can be mechanical connection, electrical connection or mutual communication; it can be direct connection, or indirect connection through an intermediary, it can be internal connection of two elements or interaction of two elements relation. 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.

In the present invention, unless otherwise expressly provided and limited, the term "above" or "below" a first feature of a second feature may include direct contact between the first and second features, or may also include the first and second features. Not in direct contact but through additional characteristic contact between them. Furthermore, the terms "above", "above" and "above" a first feature on a second feature include the first feature being directly above and diagonally above the second feature, or simply mean that the first feature is higher in level than the second feature. “Below”, “under” and “under” the first feature is the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature is less horizontally than the second feature.

The following disclosure provides many different embodiments or examples of various structures for implementing the invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the invention. Furthermore, the present invention may repeat reference numbers and/or reference letters in different examples, such repetition being for purposes of simplicity and clarity and does not itself indicate a relationship between the various embodiments and/or arrangements discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

Referring to Figure 1, Figure 2 and Figure 3, the present invention provides an actuator device for use in a zoom lens, including a transmission shaft 100, a transmission mechanism and a piezoelectric actuation system 200. The transmission shaft 100 is fixedly connected to the transmission mechanism. And the rotation is provided on the piezoelectric actuation system 200, and the transmission shaft 100 can rotate around its own axis;

The transmission mechanism includes a first fixed ring 310, a second fixed ring 320 and a third fixed ring 330. The outer diameter of the first fixed ring 310 is smaller than the inner diameter of the second fixed ring 320 and the first fixed ring 310 is fixedly connected to the transmission shaft 100. , a plurality of first support bars 340 are hinged between the first fixed ring 310 and the second fixed ring 320. When the first support bars 340 rotate relative to the first fixed ring 310, they can pull the second fixed ring 320 close to the first fixed ring 310. Or push the second fixed ring 320 away from the first fixed ring 310; the outer diameter of the second fixed ring 320 is smaller than the inner diameter of the third fixed ring 330, and there are multiple second fixed rings hinged between the second fixed ring 320 and the third fixed ring 330. Support bar 350, when the second support bar 350 rotates relative to the second fixed ring 320, it can pull the third fixed ring 330 close to the second fixed ring 320 or push the third fixed ring 330 away from the second fixed ring 320;

The piezoelectric actuation system 200 is used to drive the transmission shaft 100 to rotate to drive the first support bar 340 to rotate relative to the first fixed ring 310 and to drive the second support bar 350 to rotate relative to the second fixed ring 320 to drive the transmission mechanism along the transmission shaft 100 unfold or fold in the axial direction.

In this embodiment, when the transmission shaft 100 rotates, the angle between the first fixed ring 310 and the first support bar 340 changes, thereby driving the second fixed ring 320 to rotate and move closer to or away from the second fixed ring 320 along the axial direction of the transmission shaft 100 . A fixed ring 310. When the second fixed ring 320 rotates, the angle between the second fixed ring 320 and the second support bar 350 changes. When the third fixed ring 330 is restricted from rotating, the third fixed ring 330 rotates at the first position. Under the action of the traction or pushing force of the two support bars 350, the second fixing ring 320 can be moved closer to or away from the second fixed ring 320 along the axial direction of the transmission shaft 100, thereby achieving expansion and contraction of the transmission mechanism.

Since the outer diameter of the first fixed ring 310 is smaller than the inner diameter of the second fixed ring 320 , with proper design, the first support bar 340 can rotate to be on the same plane as the first fixed ring 310 , and at this time the second fixed ring 320 The first support bar 340 and the first fixing ring 310 are enclosed and in the same plane as the first fixing ring 310; similarly, since the outer diameter of the second fixing ring 320 is smaller than the inner diameter of the third fixing ring 330, the second support bar 340 and the first fixing ring 310 are enclosed in the same plane. The bar 350 can rotate to be in the same plane as the second fixed ring 320. At this time, the third fixed ring 330 surrounds the second support bar 350 and the second fixed ring 320 and is in the same plane as the second fixed ring 320; , the entire transmission mechanism is folded into a plane, which minimizes the volume and only occupies a flat space. When the transmission mechanism is unfolded, the maximum extension length = the length of the first support + the length of the second support. It can be seen that the transmission mechanism It has the characteristics of small size and large changing stroke, which is conducive to miniaturization and thinness.

In some embodiments, referring to Figures 1, 2 and 3, the first support bar 340 is hinged with the first fixed ring 310 and the second fixed ring 320 through a ball joint; the second support bar 350 is hinged through a ball joint. The head hinge is hinged with the second fixed ring 320 and the third fixed ring 330;

When the transmission shaft 100 rotates around its own axis, the first support bar 340 and the second support bar 350 rotate to make the second fixed ring 320 and the third fixed ring 330 move closer to or away from the first fixed ring 310 synchronously.

In this embodiment, the ball joint hinge can meet the angle changes and position changes of the first support bar 340 and the second support bar 350, and can enable the first support bar 340 and the second support bar 350 to obtain a larger range of movement. It is conducive to folding the transmission mechanism into a flat surface and unfolding the transmission mechanism to the maximum extension length; at the same time, the ball head hinge can make the first support bar 340 and the second support bar 350 move more smoothly and flexibly, which is conducive to the rapid expansion and contraction of the transmission mechanism. .

In some embodiments, referring to Figure 1, Figure 2 and Figure 3, the first support bar 340 is hinged with the first fixed ring 310 and the second fixed ring 320 through a flexible hinge; the second support bar 350 is articulated through a flexible hinge. Hinged with the second fixing ring 320 and the third fixing ring 330 .

In this embodiment, the flexible hinge has the characteristics of no mechanical friction, no gap, small space size, easy control, and high motion sensitivity. It can enable the first support bar 340 and the second support bar 350 to obtain a larger range of movement, which is conducive to implementation Fold the transmission mechanism into a flat surface and expand the transmission mechanism to the maximum extension length; at the same time, the flexible hinge can make the first support bar 340 and the second support bar 350 move more smoothly and flexibly, which is conducive to the rapid expansion and contraction of the transmission mechanism. On the other hand, the movement of the first support bar 340 and the second support bar 350 can be made more sensitive, which is beneficial to improving the control accuracy and achieving high-precision control.

In some embodiments, referring to FIG. 3 , the first fixing ring 310 , the second fixing ring 320 , the third fixing ring 330 , the first support bar 340 and the second support bar 350 are processed in one piece.

As mentioned above, when properly designed, the transmission mechanism can be folded into a flat surface. When a flexible hinge is used to connect the first support bar 340 and the second support bar 350, a flat elastic thin plate can be processed through a hollowing process. Processing, in order to obtain an integrally processed transmission mechanism, the processing process is simple, the finished product is low in cost, and is conducive to miniaturization and thinness.

In some embodiments, referring to Figures 1, 5, 6 and 7, the piezoelectric actuation system 200 includes at least one stator made of piezoelectric material. The stator is provided with an arc surface. The stator is provided with a protruding contact portion, and the contact portion is in contact with the peripheral surface of the transmission shaft 100; the stator is used to generate vibration when excited by an electrical signal to cause the corresponding contact portion to perform an elliptical movement to drive the transmission shaft 100 to rotate around its own axis.

In this embodiment, the stator may be a piece of high-strength piezoelectric ceramics, or may be a composite body combining metal and piezoelectric materials.

The stator is equivalent to a piezoelectric motor. When an electrical signal is input to the stator, the stator will produce two resonance modes. The first mode provides vertical vibration (mode 1) for the contact part, and the second mode is The contact part provides vibration in the horizontal direction (mode 2); when the input electrical signal is a sinusoidal signal of the same frequency with a phase difference of π/2, the two vibration modes drive the contact part to move cyclically and exhibit an elliptical motion. trajectory, at this time the transmission shaft 100 is in contact with the contact part and rotates around its own axis under the action of contact friction.

Specifically, for example, when the input electrical signal is a same-frequency sinusoidal signal with a phase difference of π/2, the contact portion forms an elliptical movement in the clockwise direction, and at this time, the transmission shaft 100 is driven to rotate in the counterclockwise direction; input When the electrical signal is a sinusoidal signal of the same frequency with a phase difference of -π/2, the contact part forms an elliptical movement in the counterclockwise direction, and at this time, the transmission shaft 100 is driven to rotate in the clockwise direction; thereby realizing the transmission shaft 100% forward and reverse rotation to control the expansion and contraction of the transmission mechanism.

In some embodiments, the piezoelectric actuation system 200 includes a stator. In practical applications, an elastic block can be provided on an opposite side of the stator. The elastic block abuts the transmission shaft 100 and drives the transmission shaft 100 toward the stator. By applying pressure in the direction, the elastic block and the stator have the effect of providing positive pressure on the transmission shaft 100. On the one hand, it is beneficial to prevent the transmission shaft 100 from being separated from the stator, and on the other hand, it is beneficial to ensure that the contact part remains in contact with the transmission shaft 100.

In some embodiments, the piezoelectric actuation system 200 includes a plurality of stators made of piezoelectric material, with a plurality of arcuate surfaces surrounding a circle; when the stator is excited by an electrical signal, the stator vibrates to cause the corresponding The contact part performs an elliptical motion and cooperates with the elliptical motion of other contact parts to drive the transmission shaft 100 to rotate around its own axis.

In some preferred embodiments, with reference to Figure 1, Figure 6 and Figure 7, the piezoelectric actuation system 200 includes two stators, and the two stators are respectively:

The first stator 210 is provided with a first arc surface 211. The first arc surface 211 is provided with a protruding first contact portion 212. The first contact portion 212 is in contact with the peripheral surface of the transmission shaft 100; The first stator 210 is used to generate vibration when excited by an electrical signal to cause the first contact portion 212 to perform an elliptical movement;

The second stator 220 is provided with a second arc surface 221. The second arc surface 221 is provided with a protruding second contact portion 222. The second contact portion 222 contacts the peripheral surface of the transmission shaft 100; The arc surface 221 and the first arc surface 211 form a circle; the second stator 220 is used to generate vibration when excited by an electrical signal to make the second contact part 222 perform an elliptical movement and cooperate with the elliptical movement of the first contact part 212 The drive shaft 100 rotates around its own axis.

In this embodiment, only two stators are provided to control the rotation of the transmission shaft 100, simplifying the structure, reducing the overall weight, achieving a lighter effect, and also reducing control difficulty.

In actual application, users can control the electrical signal input to achieve the following various driving methods:

The first one uses only the first stator 210 or the second stator 220 to drive the transmission shaft to rotate:

For example, only a same-frequency sinusoidal signal with a phase difference of π/2 is input to the first stator 210 to excite, causing the first contact portion 212 to perform an elliptical movement in the clockwise direction, thereby causing the transmission shaft 100 to rotate in the counterclockwise direction; only A same-frequency sinusoidal signal with a phase difference of -π/2 is input to the first stator 210 to excite, causing the first contact part 212 to perform an elliptical movement in the counterclockwise direction, thereby causing the transmission shaft 100 to rotate in the clockwise direction; and the second The stator 220 only has the effect of providing positive pressure for the transmission shaft 100 and does not play a driving role; the reverse is the same and will not be described again here.

Second, use the first stator 210 and the second stator 220 to drive the transmission shaft to rotate at the same time:

For example, a same-frequency sinusoidal signal with a phase difference of π/2 is input to both the first stator 210 and the second stator 220 to excite, so that the first contact portion 212 and the second contact portion 222 both perform elliptical movements in the clockwise direction. Then the transmission shaft 100 is rotated in the counterclockwise direction; a same-frequency sinusoidal signal with a phase difference of -π/2 is input to both the first stator 210 and the second stator 220 to excite, so that the first contact part 212 and the second contact part 222 If both perform elliptical motion in the counterclockwise direction, the transmission shaft 100 will rotate in the clockwise direction;

The third method uses the first stator 210 and the second stator 220 to drive the transmission shaft to rotate:

For example, a same-frequency sinusoidal signal with a phase difference of π/2 is input to the first stator 210 to excite, causing the first contact portion 212 to perform an elliptical movement in the clockwise direction, thereby causing the transmission shaft 100 to rotate in the counterclockwise direction; The two stators 220 are excited by inputting sinusoidal signals of the same frequency with a phase difference of -π/2, causing the second contact part 222 to perform an elliptical movement in the counterclockwise direction, thereby causing the transmission shaft 100 to rotate in the clockwise direction; and vice versa, the same principle applies here. No longer.

Among the above three driving modes, each time the transmission shaft 100 changes the direction of rotation, the first driving mode and the second driving mode need to switch electrical signals. In contrast, the third driving mode requires switching of electrical signals due to the first stator 210 and the second stator 220 each control a rotation direction of the transmission shaft 100. Therefore, there is no need to switch the respective electrical signals of the first stator 210 and the second stator 220, which reduces the difficulty of controlling the electrical signal input.

In a further preferred embodiment, only one stator is provided to control the rotation of the transmission shaft 100 .

For example, based on the above embodiment, the second stator 220 is cancelled, and only the same-frequency sinusoidal signal with a phase difference of π/2 is input to the first stator 210 to excite, so that the first contact part 212 moves elliptically in the clockwise direction. , then the transmission shaft 100 is rotated in the counterclockwise direction; only the same-frequency sinusoidal signal with a phase difference of -π/2 is input to the first stator 210 to excite, causing the first contact part 212 to perform an elliptical movement in the counterclockwise direction, then The transmission shaft 100 is rotated in the clockwise direction; vice versa, the same principle will not be repeated here.

In some embodiments, the transmission shaft 100 is specifically a cylinder, and multiple arc surfaces are formed into a circle so that it can be arranged coaxially with the transmission shaft 100 , so that the overall structure of the piezoelectric actuator system 200 and the transmission shaft 100 can better cooperate. Compact, it can effectively utilize the space of the piezoelectric actuator system 200, improve the utilization efficiency of the internal space of the piezoelectric actuator system 200, make the piezoelectric actuator system 200 miniaturized and thinner, and also facilitate the maintenance and transmission of all contact parts. The shaft 100 is in contact, and the contact portion may be located inside the transmission shaft 100 to contact the inner peripheral surface of the transmission shaft 100 , or may be located outside the transmission shaft 100 to contact the outer peripheral surface of the transmission shaft 100 .

In some embodiments, referring to FIGS. 1 , 6 and 7 , the first arc surface 211 semi-encircles the drive shaft 100 along the circumferential direction of the drive shaft 100 and the first contact portion 212 is connected to the outer circumference of the drive shaft 100 . surface contact;

The second arc surface 221 and the first arc surface 211 completely surround the transmission shaft 100 in the circumferential direction of the transmission shaft 100 , and the second contact portion 222 is in contact with the outer peripheral surface of the transmission shaft 100 .

In this embodiment, the first arc surface 211 and the second arc surface 221 are located outside the transmission shaft 100 and completely surround the transmission shaft 100. The first contact portion 212 and the second contact portion 222 are in contact with the outer peripheral surface of the transmission shaft 100 to drive the transmission. As the shaft 100 rotates, such a design makes it easier for users to observe the assembly situation between the first stator 210, the second stator 220 and the transmission shaft 100, making it convenient for users to assemble and disassemble.

In some embodiments, with reference to Figures 1, 6 and 7, a first elastic element 230 and a second elastic element 240 are provided on the stator. The first elastic element 230 is located on the side of the stator provided with an arc surface. , the second elastic element 240 is located on the side of the stator away from the first elastic element 230. Both the first elastic element 230 and the second elastic element 240 are used to provide elastic force for the stator to keep the contact portion in contact with the peripheral surface of the transmission shaft 100. .

In this embodiment, the first elastic element 230 is specifically a serpentine structure that meanders back and forth, such as a reed, and the second elastic element 240 is a cylindrical structure, such as a spring. The first elastic element 230 and the second elastic element 240 can The position of the stator is limited and an elastic force is provided for the stator to keep the contact portion in contact with the peripheral surface of the transmission shaft 100 .

Referring to Figures 1 and 4, the present invention provides a zoom lens for use in cameras, including the actuating device in the above embodiment, a lens holder 400, a first lens barrel 500, a second lens barrel 600 and a third lens. barrel 700;

The stator of the piezoelectric actuation system 200 is fixed in the lens holder 400 through the first elastic element 230 and the second elastic element 240;

The first lens barrel 500 is fixedly connected to the lens holder 400. The first lens barrel 500 is coaxial with the first fixing ring 310 and surrounds the first fixing ring 310;

The second lens barrel 600 is sleeved on the first lens barrel 500 and surrounds the second fixing ring 320;

The third lens barrel 700 is sleeved on the second lens barrel 600 and surrounds the third fixing ring 330 . The third lens barrel 700 is fixedly connected to the third fixing ring 330 and has a lens 710 installed at one end away from the second lens barrel 600 .

In this embodiment, the outer peripheral surfaces of the first lens barrel 500 and the second lens barrel 600 are both provided with bosses, and the inner peripheral surfaces of the second lens barrel 600 and the third lens barrel 700 are both provided with bosses. Grooves are provided. Between the first lens barrel 500 and the second lens barrel 600 and between the second lens barrel 600 and the third lens barrel 700, the second lens barrel 600 is realized through mutual sliding cooperation of the bosses and grooves. and the limiting and guiding of the third lens barrel 700.

It should be noted that the first lens barrel 500 is fixed on the lens holder 400 and cannot rotate or move, and under the mutual limiting effect of the boss and the groove, the second lens barrel 600 and the third lens barrel 700 can only move Moves in the axial direction of the drive shaft 100 but cannot rotate.

Among them, the third lens barrel 700 is fixedly connected to the third fixed ring 330 and is limited by the boss of the second lens barrel 600. The third lens barrel 700 cannot rotate. When the transmission shaft 100 rotates, the third lens barrel 700 It can only move along the axial direction of the transmission shaft 100 (at the same time, the second lens barrel 600 is driven to move along the axial direction of the transmission shaft 100 under the limiting effect of the groove), thereby achieving lens zoom.

The stator uses the friction force between the contact part and the transmission shaft 100 as the driving force and self-locking force. When the stator is excited, the friction force between the contact part and the transmission shaft 100 is the driving force, driving the transmission shaft 100 to rotate, and then pushing The movement of the transmission mechanism realizes the expansion and contraction of the lens barrel; when the excitation is stopped, the friction force between the contact part and the transmission shaft 100 is a self-locking force, which keeps the lens barrel stationary, so that the actuating device realizes the stepless focusing function of the lens barrel. It also has a power-off self-locking function, which not only enables adjustment of various focal lengths within its stroke, but also enables timely power-off after adjustment to keep the focal length unchanged and save energy.

In some embodiments, with reference to Figures 1 and 2, an annular boss is provided on the outer circumference of the transmission shaft 100, and the transmission shaft 100 is embedded in the lens holder 400 through the annular boss; the annular boss can connect the transmission shaft 100 The position is limited on the lens holder 400 but will not affect the rotation of the transmission shaft 100, ensuring that the transmission shaft 100 can only rotate smoothly but cannot move in the axial direction.

The present invention provides a camera, including the zoom lens in the above embodiment, which has the following advantages:

1. Fast focusing response: when the stator is excited by an electrical signal, it can start within ten milliseconds; when the excitation signal stops, it can also complete braking and self-locking within ten milliseconds. The actuator uses the stator as the driving motor and can also complete starting and braking within ten milliseconds.

2. High focusing accuracy: The vibration of the stator is at the micro-nano level, and the displacement resolution can also reach the micro-nano level. Therefore, without a sensor (in the case of an open-loop control system), the positioning accuracy of the actuator can reach Micro and nano level.

3. Silent operation: The working frequency of the stator is in the ultrasonic frequency domain (>20kHz), which is beyond the hearing range of the human ear. For users, there is no noise pollution during operation.

4. Strong environmental adaptability: The stator is made of piezoelectric ceramics or a composite of piezoelectric ceramics and metal. The environment has little impact on the performance of these materials. The stator is not affected by electromagnetic interference and other harsh environments, even at -40-80 It can also work normally in harsh environments such as °C, strong magnetism, nuclear radiation, humidity, salt spray, etc., to better meet users' performance requirements.

5. Simple structure, strong telescopicity, long zoom stroke and fast zoom speed: The actuator device has a lightweight structure and the use of a transmission mechanism allows the telescopic movement of multiple lens barrels (>3 levels) with only a single driving force (Fig. Only three lens barrels are shown in the figure. In theory, more lens barrels can be pushed. As long as the first-stage fixed ring is fixed on the transmission shaft and the last-stage fixed ring is fixed on the last-stage lens barrel, additional lens barrels can be added in the middle. Multi-level fixed ring and support), compared with existing camera zoom technology (a single driving force can only achieve the expansion and contraction of one lens barrel), this zoom device has a long zoom stroke and fast zoom speed.

In the description of this specification, reference to the terms "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the description in conjunction with the terms The specific features, structures, materials or characteristics described in the above embodiments or examples are included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

What is described above are only some embodiments of the present invention. For those of ordinary skill in the art, several modifications and improvements can be made without departing from the creative concept of the present invention, and these all belong to the protection scope of the present invention.

Claims (8)

1. An actuating device is applied to a zoom lens and is characterized by comprising a transmission shaft (100), a transmission mechanism and a piezoelectric actuating system (200), wherein the transmission shaft (100) is fixedly connected with the transmission mechanism and is rotatably arranged on the piezoelectric actuating system (200), and the transmission shaft (100) can rotate around an axis of the transmission shaft;

the transmission mechanism comprises a first fixed ring (310), a second fixed ring (320) and a third fixed ring (330), wherein the outer diameter of the first fixed ring (310) is smaller than the inner diameter of the second fixed ring (320), the first fixed ring (310) is fixedly connected to the transmission shaft (100), a plurality of first branch strips (340) are hinged between the first fixed ring (310) and the second fixed ring (320), and the first branch strips (340) can pull the second fixed ring (320) to be close to the first fixed ring (310) or push the second fixed ring (320) to be far away from the first fixed ring (310) when rotating relative to the first fixed ring (310); the outer diameter of the second fixing ring (320) is smaller than the inner diameter of the third fixing ring (330), a plurality of second branch strips (350) are hinged between the second fixing ring (320) and the third fixing ring (330), and the second branch strips (350) can pull the third fixing ring (330) to be close to the second fixing ring (320) or push the third fixing ring (330) to be far away from the second fixing ring (320) when rotating relative to the second fixing ring (320);

the piezoelectric actuation system (200) is used for driving the transmission shaft (100) to rotate so as to drive the first branch strip (340) to rotate relative to the first fixed ring (310) and drive the second branch strip (350) to rotate relative to the second fixed ring (320), so that the transmission mechanism is unfolded or folded along the axial direction of the transmission shaft (100);

the piezoelectric actuation system (200) comprises at least one stator made of piezoelectric material, wherein an arc surface is arranged on the stator, and is provided with a convex contact part which is in contact with the peripheral surface of the transmission shaft (100); the stator is used for generating vibration when being excited by an electric signal so as to enable the corresponding contact part to perform elliptical motion to drive the transmission shaft (100) to rotate around the axis of the transmission shaft;

the piezoelectric actuation system (200) comprises two stators, which are respectively:

the first stator (210), a first cambered surface (211) is arranged on the first stator (210), a first protruding contact part (212) is arranged on the first cambered surface (211), and the first contact part (212) is in contact with the peripheral surface of the transmission shaft (100); the first stator (210) is configured to generate vibrations when excited by an electrical signal to cause the first contact (212) to perform an elliptical motion;

a second stator (220), wherein a second cambered surface (221) is arranged on the second stator (220), the second cambered surface (221) is provided with a convex second contact part (222), and the second contact part (222) is in contact with the peripheral surface of the transmission shaft (100); the second cambered surface (221) and the first cambered surface (211) are surrounded into a circle; the second stator (220) is configured to vibrate when excited by an electrical signal to cause the second contact (222) to perform an elliptical motion and to drive the drive shaft (100) to rotate about its own axis in coordination with the elliptical motion of the first contact (212).

2. The actuation device according to claim 1, characterized in that the first branch (340) is hinged to the first fixing ring (310) and the second fixing ring (320) by means of a ball-head hinge; the second branch strip (350) is hinged with the second fixing ring (320) and the third fixing ring (330) through ball-head hinges;

when the transmission shaft (100) rotates around the self axis, the first branch strip (340) and the second branch strip (350) rotate so as to enable the second fixed ring (320) and the third fixed ring (330) to synchronously approach or separate from the first fixed ring (310).

3. The actuation device according to claim 1, characterized in that the first branch (340) is hinged to the first and second fixed rings (310, 320) by a flexible hinge; the second branch (350) is hinged with the second fixing ring (320) and the third fixing ring (330) through flexible hinges.

4. An actuating device according to claim 3, characterized in that the first securing ring (310), the second securing ring (320), the third securing ring (330), the first branch (340) and the second branch (350) are integrally machined.

5. The actuation device according to claim 1, characterized in that the first cambered surface (211) partly surrounds the drive shaft (100) in the circumferential direction of the drive shaft (100) and the first contact portion (212) is in contact with the outer circumferential surface of the drive shaft (100);

the second cambered surface (221) and the first cambered surface (211) fully surround the transmission shaft (100) along the circumferential direction of the transmission shaft (100), and the second contact part (222) is in contact with the outer circumferential surface of the transmission shaft (100).

6. The actuating device according to claim 1, characterized in that a first elastic element (230) and a second elastic element (240) are provided on the stator, the first elastic element (230) being located on the side of the stator where the cambered surface is provided, the second elastic element (240) being located on the side of the stator remote from the first elastic element (230), the first elastic element (230) and the second elastic element (240) each being arranged to provide an elastic force for the stator to keep the contact portion in contact with the circumferential surface of the drive shaft (100).

7. A zoom lens applied to a camera, characterized by comprising an actuating device as claimed in any one of the preceding claims 1-6, a lens mount (400), a first barrel (500), a second barrel (600) and a third barrel (700);

the stator of the piezoelectric actuation system (200) is fixed in the lens base (400) through a first elastic element (230) and a second elastic element (240);

the first lens barrel (500) is fixedly connected to the lens base (400), and the first lens barrel (500) is coaxial with the first fixed ring (310) and surrounds the first fixed ring (310);

the second lens barrel (600) is sleeved on the first lens barrel (500) and surrounds the second fixing ring (320);

the third lens cone (700) is sleeved on the second lens cone (600) and surrounds the third fixing ring (330), and the third lens cone (700) is fixedly connected with the third fixing ring (330) and is far away from one end of the second lens cone (600) to be provided with a lens (710).

8. A camera comprising a zoom lens as claimed in claim 7.