Lens driving device

Abstract

This invention discloses a lens driving device, including a carrier, a base, an upper spring, a lower spring, and a piezoelectric driving mechanism. The carrier has a lens mounting hole for mounting a lens. The base includes a bottom plate and a first baffle and a second baffle extending upward from opposite sides of the bottom plate. The upper spring connects the top of the carrier to the top of the first baffle, and the lower spring connects the base to the bottom of the carrier. The piezoelectric driving mechanism includes a friction plate, a piezoelectric block, and a friction rod. The friction plate is fixedly disposed on the side of the carrier, the piezoelectric block is fixedly disposed on the second baffle, one end of the friction rod is fixedly connected to the piezoelectric block, and the other end of the friction rod contacts the friction plate. When the piezoelectric block is energized, it moves along the optical axis and drives the carrier to move along the optical axis through the friction rod and friction plate. The piezoelectric driving device of this invention has the beneficial technical effects of high displacement control accuracy and fast response speed.

Description

Technical Field

[0001] This invention relates to the field of optical drive, and more specifically to a lens drive device. Background Technology

[0002] Traditional lens drive motors are typically installed inside the phone's camera module and are usually driven by an electromagnetic combination of magnets and coils, generating magnetic fields that can interfere with other electronic components inside the phone. Furthermore, they often use auxiliary components such as suspension wires and springs, which are susceptible to metal fatigue and irreversible deformation after impact. Summary of the Invention

[0003] The purpose of this invention is to provide a lens driving device to solve the problems existing in the prior art.

[0004] To address the above problems, according to one aspect of the present invention, a lens driving device is provided, the lens driving device comprising:

[0005] The carrier is provided with a lens mounting hole for mounting a lens.

[0006] The base includes a base plate and a first baffle and a second baffle extending upward from opposite sides of the base plate.

[0007] An upper spring plate connects the top of the carrier to the top of the first baffle.

[0008] A lower spring connects the base to the bottom of the carrier.

[0009] The piezoelectric drive mechanism includes a friction plate, a piezoelectric block, and a friction rod. The friction plate is fixedly disposed on the side of the carrier, the piezoelectric block is fixedly disposed on the second baffle, one end of the friction rod is fixedly connected to the piezoelectric block, and the other end of the friction rod is in contact with the friction plate. When the piezoelectric block is energized, it moves along the optical axis and drives the carrier to move along the optical axis through the friction rod and the friction plate.

[0010] In one embodiment, the lens driving device further includes a circuit board disposed on the outer surface of the second baffle and electrically connected to the piezoelectric block.

[0011] In one embodiment, the lens driving device further includes a sensor and a sensor magnet, the sensor magnet being disposed on the side of the carrier, and the sensor being disposed on the circuit board and cooperating with the sensor magnet to detect the position of the carrier.

[0012] In one embodiment, the base connection portions of the upper spring and the lower spring are respectively fixed on the base, and the carrier connection portions of the upper spring and the lower spring are respectively fixed on the carrier. The friction pad on the carrier is pressed onto the friction rod by the elastic force between the carrier connection portions and the base connection portions of the upper spring and the lower spring.

[0013] In one embodiment, the second baffle is provided with a piezoelectric block mounting groove and a sensor clearance groove. The opening of the piezoelectric block mounting groove is located at the top of the second baffle and extends downward a certain distance to form the bottom of the piezoelectric block mounting groove. The sensor clearance groove is located on one side of the piezoelectric block mounting groove. The piezoelectric block is installed in the piezoelectric block mounting groove and can vibrate up and down along the optical axis in the piezoelectric block mounting groove. The sensor is arranged in the sensor clearance groove.

[0014] In one embodiment, the outer surface of the second baffle is further provided with a circuit board mounting groove, the circuit board is arranged in the circuit board mounting groove, and the piezoelectric block mounting groove and the sensor clearance groove are arranged in the circuit board mounting groove.

[0015] In one embodiment, the first baffle has lower spring mounting steps at both ends, and the base connection of the lower spring is fixed to the surface of the lower spring mounting steps.

[0016] In one embodiment, the upper spring connecting portions are provided at both ends of the upper surface of the first baffle, and the base connecting portion of the upper spring is fixed on the upper spring connecting portion.

[0017] In one embodiment, the lower spring forms a U-shaped structure, with the open ends of the U-shaped structure forming the base connection portion of the lower spring and the bottom of the U-shaped structure forming the carrier connection portion of the lower spring.

[0018] In one embodiment, the carrier has a first side opposite to the first baffle and a second side opposite to the baffle. The top end of the first side is provided with an upper spring carrier connection portion, and the second side is provided with a friction plate mounting groove and a sensing magnet mounting groove. The friction plate mounting groove extends downward from the top end of the second side to the bottom end of the second side, and the sensing magnet mounting groove is disposed on the side of the friction plate mounting groove.

[0019] In one embodiment, the lens driving device further includes a housing, which cooperates with the base to form a cavity, and the carrier, upper spring, lower spring, and piezoelectric driving mechanism are disposed in the cavity.

[0020] Compared with traditional electromagnetic driving methods, the piezoelectric driving device of this invention uses piezoelectric drive, which can avoid electromagnetic interference and eliminates the need for a transmission mechanism, thus offering the advantages of high displacement control accuracy and fast response speed. Furthermore, this invention isolates the piezoelectric block from the friction plate by placing a friction rod between the piezoelectric block and the friction plate, preventing direct contact between them. Attached Figure Description

[0021] Figure 1 This is an exploded perspective view of a lens driving device according to an embodiment of the present invention.

[0022] Figure 2 This is a perspective view of the base according to an embodiment of the present invention.

[0023] Figure 3 This is a perspective view of the upper spring sheet according to an embodiment of the present invention.

[0024] Figure 4 This is a perspective view of the lower spring sheet according to an embodiment of the present invention.

[0025] Figure 5 This is a cross-sectional view of a piezoelectric drive device according to an embodiment of the present invention. Detailed Implementation

[0026] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so as to better understand the purpose, features and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are only for illustrating the essential spirit of the technical solution of the present invention.

[0027] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0028] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0029] In the following description, in order to clearly demonstrate the structure and working method of the present invention, a number of directional terms will be used. However, terms such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and not as limiting terms.

[0030] This invention relates to a lens driving device, which can be used in electronic devices such as mobile phone cameras and laptop cameras to drive lens movement to achieve optical zoom. Compared with traditional electromagnetic driving methods, this invention uses piezoelectric driving, which avoids electromagnetic interference and eliminates the need for a transmission mechanism, resulting in high displacement control accuracy and fast response speed. Furthermore, this invention avoids direct contact between the piezoelectric block and the friction plate by placing a friction rod between the piezoelectric block and the friction plate, thus isolating them.

[0031] Figure 1 This is an exploded perspective view of a lens driving device 100 according to an embodiment of the present invention. Figure 2 This is a perspective view of the base 10 according to an embodiment of the present invention, as shown below. Figure 1-2 As shown, a lens driving device 100 according to an embodiment of the present invention includes a carrier 10, a base 20, an upper spring 30, a lower spring 40, and a piezoelectric driving mechanism 50. The carrier 10 is provided with a lens mounting hole 11 for mounting a lens. The base 20 includes a bottom plate 21 and a first baffle 22 and a second baffle 23 extending upward from opposite sides of the bottom plate 21. The upper spring 30 connects the top of the carrier 10 to the top of the first baffle 22, and the lower spring 40 connects the base 20 to the bottom of the carrier 10. The piezoelectric drive mechanism 50 includes a friction plate 51, a piezoelectric block 52, and a friction rod 53. The friction plate 51 is fixedly disposed on the side of the carrier 10, and the piezoelectric block 52 is fixedly disposed on the second baffle 23 of the base 10. One end of the friction rod 53 is fixedly connected to the piezoelectric block 52, and the other end of the friction rod 53 is in contact with the friction plate 51. When the piezoelectric block 52 is energized, it moves along the optical axis. Since one end of the friction rod 53 is fixedly connected to the inner surface of the piezoelectric block 52, when the piezoelectric block 52 is energized and vibrates, it will drive the friction rod 53 to vibrate. The other end of the friction rod 53 is in contact with the friction plate, which is fixed on the carrier. Thus, the vibration is transmitted to the carrier 10 through the friction plate. Since the vibration direction of the piezoelectric block 52 is along the optical axis, the piezoelectric drive mechanism can drive the carrier 10 to move along the optical axis. A lens (not shown) is installed in the lens mounting hole 11 of the carrier 10, which can drive the lens to move along the optical axis to achieve optical zoom function. Compared to traditional electromagnetic drive technology, this invention utilizes piezoelectric drive, completely eliminating and avoiding electromagnetic interference problems. Furthermore, through a unique structural design, it achieves a breakthrough in drive methods while maintaining the original product size, possessing broad commercial application value.

[0032] Optionally, the lens drive device 100 also includes a circuit board 60, which is disposed on the outer surface of the second baffle 23 and electrically connected to the piezoelectric block 52, and provides current to the piezoelectric block 52 through the circuit board 60.

[0033] Optionally, the lens drive device 100 also includes a housing 80, which cooperates with the base 20 to form a cavity, and the carrier 10, the upper spring 30, the lower spring 40 and the piezoelectric drive mechanism 50 are disposed in the cavity.

[0034] In one embodiment, the lens driving device 100 further includes a sensor 71 and a sensor magnet 72. The sensor magnet 72 is fixedly disposed on the side of the carrier 10, and the sensor 71 is disposed on the circuit board 60 and cooperates with the sensor magnet 72 to detect the position of the carrier 10. That is, since the sensor magnet is fixedly installed on the carrier, when the piezoelectric block driving mechanism drives the carrier to move, the sensor magnet 72 moves with the carrier 10. Thus, the displacement of the carrier can be obtained by detecting the position of the sensor magnet, and the position information can be transmitted to the control module of an electronic device such as a mobile phone to further adjust the current of the piezoelectric block, thereby controlling the movement position of the carrier and achieving the ideal focusing effect. Optionally, the sensor can be a Hall sensor, which can accurately collect the displacement of the carrier 10.

[0035] Figure 3 This is a perspective view of the upper spring sheet according to an embodiment of the present invention. Figure 4 This is a perspective view of the lower spring sheet according to an embodiment of the present invention, as shown below. Figure 3-4 As shown, in one embodiment, the upper spring 30 is provided with an upper spring base connecting part 31 and an upper spring carrier connecting part 32, which are connected by an elastic element. The lower spring 40 is provided with a lower spring base connecting part 41 and a lower spring carrier connecting part 42, which are connected by an elastic element. The upper spring base connecting part 31 is fixed to the top of the first baffle 22 of the base 20, and the lower spring base connecting part 41 is fixed to both ends of the second baffle. The upper spring carrier connecting part 32 is fixed to the upper surface of the carrier 10, and the lower spring carrier connecting part 42 is fixed to the lower surface of the carrier. The friction plate 51 on the carrier 10 is pressed onto the friction rod 53 by the elastic element connecting the upper spring carrier connecting part and the upper spring base connecting part, and the elastic force connecting the lower spring base connecting part and the lower spring carrier connecting part, so that the vibration of the piezoelectric block can interact efficiently with the friction plate, thereby transmitting the motion to the carrier.

[0036] Reference Figure 2Optionally, the second baffle 23 is provided with a piezoelectric block mounting groove 231 and a sensor clearance groove 232. The opening of the piezoelectric block mounting groove 231 is located at the top of the second baffle and extends downward a certain distance to form the bottom of the piezoelectric block mounting groove. That is, the piezoelectric block mounting groove 231 is set as a top-open structure. After the piezoelectric block is placed in the piezoelectric block mounting groove, the bottom of the piezoelectric block is restricted, while the top is open. Thus, the piezoelectric block can be installed in the piezoelectric block mounting groove 231 and can vibrate up and down along the optical axis in the piezoelectric block mounting groove 231. The sensor clearance groove 232 is located on one side of the piezoelectric block mounting groove 231. The sensor 71 is arranged in the sensor clearance groove 232. The sensor 71 is fixed on the inner surface of the circuit board 60 and located in the sensor clearance groove 232, and faces and cooperates with the sensor magnet 72 to detect the displacement information of the sensor magnet.

[0037] In one embodiment, the outer surface of the second baffle 23 is further provided with a circuit board mounting groove 233. The circuit board mounting groove 233 is formed by sinking on the outer surface of the second baffle and is open at the top and bottom. That is, the entire circuit board mounting groove 233 extends upward and downward to the top and bottom of the second baffle to form a through groove. The circuit board 60 is arranged in the circuit board mounting groove 233, and the piezoelectric block mounting groove 231 and the sensor clearance groove 232 are arranged in the area where the circuit board mounting groove 233 is located.

[0038] In one embodiment, the first baffle 22 has lower spring mounting steps 221 at both ends, and the base connection part 41 of the lower spring 40 is fixed to the surface of the lower spring mounting steps 221.

[0039] In one embodiment, the upper surface of the first baffle 22 is provided with upper spring connecting portions 222 at both ends, and the base connecting portion 31 of the upper spring 30 is fixed on the upper spring connecting portion 222.

[0040] The base is connected to the carrier by the upper and lower spring plates, ensuring that the spring plates pull both ends of the carrier tightly to the second baffle of the base, ensuring uniform force, so that the friction rod always keeps in close contact with the friction plate during the vibration of the piezoelectric block, achieving a highly efficient piezoelectric drive effect.

[0041] Figure 3 This is a perspective view of the lower spring 40 according to an embodiment of the present invention, as shown below. Figure 4 As shown, in one embodiment, the lower spring 40 forms a letter "U" shape, with the open ends of the "U" shape forming a lower spring base connection portion 41, and the bottom of the "U" shape forming a lower spring carrier connection portion 42.

[0042] Figure 4 This is a perspective view of the carrier 10 according to an embodiment of the present invention, as shown below. Figure 4As shown, in one embodiment, the carrier 10 has a first side 12 opposite to the first baffle 22 and a second side 13 opposite to the second baffle 23. The top end of the first side 12 is provided with an upper spring carrier connecting part 121, and the second side 13 is provided with a friction plate mounting groove 131 and a sensing magnet mounting groove 132. The friction plate mounting groove extends downward from the top end of the second side to the bottom end of the second side and forms an open groove at the top and bottom. The friction plate is fixedly installed in the friction plate mounting groove 131, and the sensing magnet mounting groove 132 is disposed on the side of the friction plate mounting groove. The sensor magnet 72 is fixedly installed in the sensing magnet mounting groove 132.

[0043] Figure 5 This is a cross-sectional view of a piezoelectric drive device 100 according to an embodiment of the present invention. To clearly show the structure of the piezoelectric drive mechanism, the carrier is moved a certain distance to the right of the figure, so that the friction rod and the friction plate are spaced a certain distance apart, as shown. Figure 5 As shown, the piezoelectric block 52 is fixed to the base 20 and electrically connected to the circuit board 60. The rear end of the friction rod 53 is fixed to the piezoelectric block 52, and the friction plate 51 is fixed to the carrier 10. Due to the upper and lower spring plates applying force to the carrier... Figure 5 The force on the right side, as shown, pushes the carrier towards the second baffle of the base 20, causing the friction plate 51 to press against the friction rod 53. When the piezoelectric block 52 is energized and vibrates along the optical axis, it drives the friction rod 53 to move, and transmits the motion to the carrier through contact with the friction plate 51, thereby driving the carrier to move along the optical axis and achieving optical zoom. Since the entire driving process does not require the use of magnets, coils, or other structures, the overall structure of the lens driving device is simple, the power transmission is efficient, and it has broad commercial application prospects.

[0044] The preferred embodiments of the present invention have been described in detail above. However, it should be understood that after reading the above teachings, those skilled in the art can make various alterations or modifications to the present invention. These equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A lens driving device, characterized in that, The lens driving device includes: The carrier is provided with a lens mounting hole for mounting a lens. The base includes a base plate and a first baffle and a second baffle extending upward from opposite sides of the base plate. An upper spring connects the top of the carrier to the top of the first baffle. The upper spring has an upper spring base connecting part and an upper spring carrier connecting part, which are connected by an elastic element. The upper spring base connecting part is fixed to the top of the first baffle, and the upper spring carrier connecting part is fixed to the upper surface of the carrier. A lower spring connects the base to the bottom of the carrier. The lower spring has a lower spring base connecting portion and a lower spring carrier connecting portion, which are connected by an elastic element. The lower spring base connecting portion is fixed to both ends of the first baffle, and the lower spring carrier connecting portion is fixed to the lower surface of the carrier. A piezoelectric drive mechanism includes a friction plate, a piezoelectric block, and a friction rod. The friction plate is fixedly disposed on the side of the carrier, the piezoelectric block is fixedly disposed on the second baffle, one end of the friction rod is fixedly connected to the piezoelectric block, and the other end of the friction rod contacts the friction plate. The friction plate on the carrier is pressed onto the friction rod by the elastic force between the elastic element connecting the upper spring carrier connection part and the upper spring base connection part and the elastic element connecting the lower spring base connection part and the lower spring carrier connection part. When the piezoelectric block is energized, it moves along the optical axis and drives the carrier to move along the optical axis through the cooperation of the friction rod and the friction plate.

2. The lens driving device according to claim 1, characterized in that, The lens driving device also includes a circuit board, which is disposed on the outer surface of the second baffle and electrically connected to the piezoelectric block.

3. The lens driving device according to claim 2, wherein The lens driving device also includes a sensor and a sensor magnet. The sensor magnet is disposed on the side of the carrier, and the sensor is disposed on the circuit board and cooperates with the sensor magnet to detect the position of the carrier.

4. The lens driving device according to claim 2, wherein The second baffle is provided with a piezoelectric block mounting groove and a sensor clearance groove. The opening of the piezoelectric block mounting groove is located at the top of the second baffle and extends downward a certain distance to form the bottom of the piezoelectric block mounting groove. The sensor clearance groove is located on one side of the piezoelectric block mounting groove. The piezoelectric block is installed in the piezoelectric block mounting groove and can vibrate up and down along the optical axis in the piezoelectric block mounting groove. The sensor is arranged in the sensor clearance groove.

5. The lens driving apparatus according to claim 4, wherein The outer surface of the second baffle is also provided with a circuit board mounting groove, the circuit board is arranged in the circuit board mounting groove, and the piezoelectric block mounting groove and the sensor clearance groove are arranged in the circuit board mounting groove.

6. The lens driving apparatus according to claim 1, wherein The first baffle has lower spring mounting steps at both ends, and the base connection of the lower spring is fixed to the surface of the lower spring mounting steps.

7. The lens driving apparatus according to claim 1, wherein The upper surface of the first baffle is provided with the upper spring connecting parts at both ends, and the base connecting part of the upper spring is fixed on the upper spring connecting parts.

8. The lens driving apparatus according to claim 1, wherein The lower spring forms a U-shaped structure, with the open ends of the U-shaped structure forming the base connection portion of the lower spring and the bottom of the U-shaped structure forming the carrier connection portion of the lower spring.

9. The lens driving apparatus according to claim 1, wherein The carrier has a first side opposite to the first baffle and a second side opposite to the baffle. The top of the first side is provided with an upper spring carrier connecting part, and the second side is provided with a friction plate mounting groove and a sensing magnet mounting groove. The friction plate mounting groove extends downward from the top of the second side to the bottom of the second side, and the sensing magnet mounting groove is disposed on the side of the friction plate mounting groove.

10. The lens driving device according to claim 1, characterized in that, The lens driving device also includes a housing, which cooperates with the base to form a cavity, and the carrier, upper spring, lower spring and piezoelectric driving mechanism are disposed in the cavity.

Images