Lens-driving device

Abstract

A lens-driving device, comprising a housing, a magnetic steel assembly, a circuit board assembly, an elastic bracket, a driving coil assembly and an image sensor, wherein the image sensor is arranged opposite an opening in an optical axis direction; the magnetic steel assembly and the driving coil assembly are arranged opposite each other in the optical axis direction so as to drive the image sensor to move relative to the housing in a direction perpendicular to the optical axis direction; the circuit board assembly comprises a first circuit board and a second circuit board that are stacked and fixed on the elastic bracket, the second circuit board being connected to the first circuit board; the driving coil assembly is fixed to the side of the first circuit board facing the magnetic steel assembly; the second circuit board electrically connects the first circuit board to an external circuit; and the first circuit board is a PCB, the second circuit board is an FPC, and the first circuit board and the second circuit board are integrally formed. Compared with the prior art, the lens-driving device has a compact structure, saves on space, and has a good image-stabilization driving effect.

Description

Lens drive device Technical Field

[0001] This utility model relates to the field of image stabilization technology, and in particular to a lens driving device. Background Technology

[0002] As consumers demand a better shooting experience, image stabilization features of lens drive mechanisms are widely used in various video recording devices. The integration of lens drive mechanisms with various portable electronic devices such as mobile phones, camcorders, and computers is also gaining popularity among consumers. Technical issues

[0003] Lens driving devices of related technologies generally include a housing, a circuit board disposed within the housing, magnets or coils fixed on the circuit board, coils or magnets fixed to the housing, and a lens bracket fixed to the circuit board. The circuit board is structurally strong by stacking and soldering multiple circuit boards. The lens module is fixed to the lens bracket, and the circuit board is elastically supported by spring contacts. When current is applied to the coil, the coil and the magnet assembly generate an electromagnetic field. The coil experiences a Lorentz force from this electromagnetic field, driving the lens bracket to move perpendicular to the optical axis, thereby enabling the lens module to achieve image stabilization. However, in this lens driving device, the spring contacts that elastically support the circuit board are costly to manufacture. Furthermore, the method of stacking and soldering circuit boards to form a single unit to support the lens bracket increases the overall height of the lens driving device, resulting in poor space utilization.

[0004] Therefore, it is necessary to provide a new lens driving device to solve the above-mentioned technical problems. Technical solutions

[0005] The purpose of this invention is to provide a lens driving device with a small overall size, good driving effect, and better image stabilization effect.

[0006] To achieve the above objectives, this utility model provides a lens driving device, including a housing, a magnet assembly fixed to the housing, a circuit board assembly suspended within the housing, an elastic bracket supporting the circuit board assembly on the housing, a drive coil assembly stacked and fixed to the circuit board assembly and electrically connected to the circuit board assembly, and an image sensor fixed to the circuit board assembly; the housing has an opening extending through it along the optical axis of the image sensor, and the image sensor is disposed opposite to the opening along the optical axis; the magnet assembly and the drive coil assembly are disposed opposite to each other along the optical axis to drive the image sensor to move relative to the housing in a direction perpendicular to the optical axis;

[0007] The circuit board assembly includes a first circuit board stacked and fixed to the elastic bracket and a second circuit board connected to the first circuit board; the drive coil assembly is fixed to the side of the first circuit board facing the magnet assembly; the second circuit board electrically connects the first circuit board to an external circuit.

[0008] The first circuit board is a PCB circuit board, and the second circuit board is an FPC circuit board. The first circuit board and the second circuit board are integrally formed.

[0009] Preferably, the thickness of the first circuit board is greater than the thickness of the second circuit board.

[0010] Preferably, the second circuit board includes a circuit board body, a flexible extension portion formed by extending the circuit board body away from the first circuit board, a connecting portion formed by bending and extending the circuit board body from opposite ends toward the first circuit board, and a fixing portion formed by bending and extending the connecting portion toward the first circuit board; the circuit board body is spaced apart from the first circuit board, and the fixing portion is fixed to the first circuit board.

[0011] The housing has a clearance groove formed through one side perpendicular to the optical axis, and the flexible extension passes through the clearance groove to be electrically connected to an external circuit.

[0012] Preferably, the drive coil assembly includes a coil substrate stacked and fixed to the first circuit board and a drive coil fixed to the side of the coil substrate facing the magnet assembly.

[0013] Preferably, the magnet assembly interacts with the drive coil assembly to drive the image sensor to move along a first direction and a second direction perpendicular to the optical axis, wherein the first direction is perpendicular to the second direction. The lens driving device further includes an anti-collision assembly fixed to the first circuit board. The anti-collision assembly includes a first anti-collision block fixed to opposite sides of the first circuit board along the first direction and a second anti-collision block fixed to opposite sides of the first circuit board along the second direction.

[0014] Preferably, the lens driving device further includes a connector, with the first anti-collision block and the second anti-collision block respectively fixed at both ends of the connector.

[0015] Preferably, the housing includes a bottom cover and an upper cover fixed to the bottom cover; the elastic bracket includes a bracket body disposed inside the upper cover, a first mounting portion and a second mounting portion extending from both ends of the bracket body toward the side close to the circuit board assembly; the circuit board assembly is fixed to the first mounting portion, the second mounting portion is fixed to the bottom cover, and the magnet assembly is fixed to the upper cover.

[0016] The upper cover includes a rectangular upper cover body, a support portion extending from one end of the upper cover body away from the bottom cover, the support portion forming the opening, and the upper cover also includes a first damping portion and a second damping portion extending from the inner edge of the support portion toward the bottom cover by bending.

[0017] The first damping part extends into the first limiting groove, and the second damping part extends into the second limiting groove.

[0018] Preferably, the width of the first damping portion parallel to the first direction is the same as the width parallel to the second direction; the width of the second damping portion parallel to the first direction is the same as the width parallel to the second direction.

[0019] Preferably, the first circuit board has a through hole extending through it along the optical axis. The lens driving device further includes a sensor bracket fixed to the first circuit board. The sensor bracket is fixed to the first circuit board and covers the through hole. The image sensor is fixed to the side of the sensor bracket facing the opening and located inside the through hole. Beneficial effects

[0020] Compared with the prior art, in the lens driving device of this utility model, the driving coil assembly and the magnet assembly are respectively fixed on the circuit board assembly and the housing. The driving coil assembly and the magnet assembly are spaced apart. The housing has an opening that runs through it along the optical axis of the image sensor. The image sensor is arranged opposite to the opening along the optical axis. The magnet assembly and the driving coil assembly are arranged opposite to each other along the optical axis to drive the image sensor to move relative to the housing in a direction perpendicular to the optical axis. The circuit board assembly includes a first circuit board stacked and fixed on one side of an elastic bracket and a second circuit board connected to the first circuit board. The driving coil assembly is fixed on the side of the first circuit board facing the magnet assembly. The second circuit board electrically connects the first circuit board to an external circuit. The first circuit board is a PCB circuit board, and the second circuit board is an FPC circuit board. By combining the first circuit board and the second circuit board, the stacking height of the circuit board assembly is further reduced. The first circuit board and the second circuit board are formed as a single structure, reducing the soldering between the first circuit board and the second circuit board, which can save the necessary stacking height along the optical axis during soldering, thereby reducing the overall stacking height and making the best use of the installation space. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0022] Figure 1 is a three-dimensional structural schematic diagram of the lens driving device provided in an embodiment of the present utility model;

[0023] Figure 2 is a partial exploded view of the lens driving device provided in an embodiment of the present invention;

[0024] Figure 3 is an exploded perspective view of the lens driving device provided in an embodiment of the present invention.

[0025] Figure 4 is a cross-sectional view along line AA in Figure 1;

[0026] Figure 5 is a cross-sectional view along line BB in Figure 1;

[0027] Figure 6 is a top view of the anti-collision component provided in an embodiment of this utility model;

[0028] Figure 7 is a schematic diagram of the circuit board assembly provided in an embodiment of this utility model.

[0029] In the diagram, 100 is the lens drive device; 1 is the housing; 101 is the bottom cover; 102 is the top cover; 1021 is the top cover body; 1022 is the support part; 1023 is the first damping part; 1024 is the second damping part; 1025 is the opening; 1026 is the perforation; 1027 is the clearance groove; 2 is the elastic bracket; 21 is the bracket body; 22 is the first mounting part; 23 is the second mounting part; 3 is the circuit board assembly; 31 is the first circuit board; 311 is the through hole; 32 is the second circuit board; 321 is the circuit board body; 322 is the flexible extension part; 323 is the connecting part; 32 4. Fixing part; 4. Drive coil assembly; 41. Coil substrate; 42. Drive coil; 421. First coil group; 422. Second coil group; 5. Magnet assembly; 51. First magnet unit; 52. Second magnet unit; 6. First magnetic conductive sheet; 7. Second magnetic conductive sheet; 8. Frame; 9. Anti-collision assembly; 91. First anti-collision block; 911. First limiting groove; 92. Second anti-collision block; 921. Second limiting groove; 93. Connector; 10. Image sensor; 11. First driving chip; 12. Second driving chip; 13. Filter; 14. Sensor bracket. Embodiments of the present invention

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0031] Referring to Figures 1 to 7, this embodiment of the present invention provides a lens driving device 100, including a housing 1, a magnet assembly 5 fixed to the housing 1, a circuit board assembly 3 suspended inside the housing 1, an elastic bracket 2 supporting the circuit board assembly 3 on the housing 1, a drive coil assembly 4 stacked and fixed to the circuit board assembly 3 and electrically connected to the circuit board assembly 3, and an image sensor 10 fixed to the circuit board assembly 3; the housing 1 has an opening 1025 extending through it along the optical axis of the image sensor 10; the image sensor 10 is disposed opposite to the opening 1025 along the optical axis; the drive coil assembly 4 is spaced apart from the magnet assembly 5; the magnet assembly 5 and the drive coil assembly 4 are disposed opposite to each other along the optical axis to drive the image sensor 10 to move relative to the housing in a direction perpendicular to the optical axis.

[0032] Optionally, the lens driving device 100 further includes a frame 8 and a filter 13, wherein the frame 8 is opposite to the opening 1025 and fixed to the circuit board assembly 3, and the filter 13 is mounted and fixed to the frame 8.

[0033] The circuit board assembly 3 includes a first circuit board 31 stacked and fixed to the elastic bracket 2 and a second circuit board 32 connected to the first circuit board 31; the drive coil assembly 4 is fixed to the side of the first circuit board 31 facing the magnet assembly 5; the second circuit board 32 electrically connects the first circuit board 31 to an external circuit. The first circuit board 31 and the second circuit board 32 are integrally formed, reducing the soldering between them and saving the necessary stacking height along the optical axis during soldering, thus reducing the overall stacking height and maximizing the use of installation space. The first circuit board 31 is a PCB circuit board, which is a rigid circuit board with high structural strength and good support. The second circuit board 32 is an FPC circuit board, which is flexible, thin, and saves stacking height along the optical axis. Therefore, through the combination of rigid and flexible components of the first circuit board 31 and the second circuit board 32, the stacking height of the circuit board assembly 3 is further reduced.

[0034] Specifically, the second circuit board 32 is connected to the periphery of the first circuit board 31 along the optical axis of the image sensor 10. The first circuit board 31 and the second circuit board 32 do not overlap, so that the circuit board assembly 3 has a small stacking height.

[0035] In this embodiment, the thickness of the first circuit board 31 is greater than the thickness of the second circuit board 32. This results in high structural strength and good support performance for the first circuit board 31.

[0036] In this embodiment, the second circuit board 32 includes a circuit board body 321, a flexible extension portion 322 extending from the circuit board body 321 away from the first circuit board 31, a connecting portion 323 extending from opposite ends of the circuit board body 321 towards the first circuit board, and a fixing portion 324 extending from the connecting portion 323 towards the first circuit board. The circuit board body 321 is spaced apart from the first circuit board 31, and the fixing portion 324 is fixed to the first circuit board 321. The housing 1 has a clearance groove 1027 extending through one side perpendicular to the optical axis, and the flexible extension portion 322 passes through the clearance groove 1027 to be electrically connected to an external circuit. This facilitates the supply of power to the drive coil assembly 4 through the flexible extension portion 1027.

[0037] In this embodiment, the drive coil assembly 4 includes a coil substrate 41 stacked and fixed to the first circuit board 31 and a drive coil 42 fixed to the side of the coil substrate 41 facing the magnet assembly.

[0038] In this embodiment, the magnet assembly 5 interacts with the drive coil assembly 4 to drive the image sensor 10 to move along a first direction X perpendicular to the optical axis and a second direction Y perpendicular to the optical axis, wherein the first direction X is perpendicular to the second direction Y.

[0039] The lens driving device 100 further includes an anti-collision assembly 9 fixed to the first circuit board; the anti-collision assembly 9 includes a first anti-collision block 91 fixed to opposite sides of the first circuit board 31 along the first direction X, and a second anti-collision block 92 fixed to opposite sides of the first circuit board 31 along the second direction Y. The first anti-collision block 91 and the second anti-collision block 92 can prevent the circuit board assembly 3 carrying the image sensor 10 from colliding with the housing 1 when it moves, thereby improving motion stability. They can also limit the rotation position of the frame 8, preventing the image sensor 10 from rotating too much, thus ensuring high safety.

[0040] In this embodiment, the lens driving device 100 further includes a connector 93, with the first anti-collision block 91 and the second anti-collision block 92 respectively fixed at both ends of the connector 93. By providing the connector 93, the stability of the first anti-collision block 91 and the second anti-collision block 92 can be increased. It can be understood that there are four connectors 93, with one connector 93 between each adjacent first anti-collision block 91 and second anti-collision block 92.

[0041] In this embodiment, the housing 1 includes a bottom cover 101 and an upper cover 102 fixed to the bottom cover 101. The elastic bracket 2 includes a bracket body 21 disposed inside the upper cover 102, and a first mounting portion 22 and a second mounting portion 23 extending from both ends of the bracket body 21 toward the side near the circuit board assembly 3, respectively; the circuit board assembly 3 is fixed to the first mounting portion 22, and the second mounting portion 23 is fixed to the bottom cover 101. The magnet assembly 5 is fixed to the upper cover 102. The opening 1025 is formed on the upper cover 102.

[0042] In this embodiment, the first anti-collision block 91 is provided with a first limiting groove 911 formed by recessing from the side near the upper cover 102 to the side away from the upper cover 102, and the second anti-collision block 92 is provided with a second limiting groove 921 formed by recessing from the side near the upper cover 102 to the side away from the upper cover 102. The upper cover 102 includes an upper cover body 1021 in the shape of a rectangular frame, and a support portion 1022 extending from the side of the upper cover body 1021 away from the bottom cover 101 toward its inner periphery. The support portion 1022 surrounds the opening. The upper cover 102 also includes a first damping portion 1023 and a second damping portion 1024 extending from the inner periphery of the support portion 1022 toward the bottom cover 101 by bending. The first damping portion 1023 and the second damping portion 1024 are respectively disposed in the first limiting groove 911 and the second limiting groove 921. The clearance groove 1027 is formed through one side of the upper cover body 1021.

[0043] In this embodiment, the first damping portion 1023 and the second damping portion 1024 have the same structure; the width of the first damping portion 1023 on the side parallel to the first direction X and the width on the side parallel to the second direction Y are the same. The width of the second damping portion 1024 on the side parallel to the first direction X and the width on the side parallel to the second direction Y are the same. The widths of the first direction X and the second direction Y, which are perpendicular to each other and both perpendicular to the optical axis, are the same. The first damping portion 1023 and the second damping portion 1024 are arranged with a stamped laminated structure, maintaining consistent dimensions in the thickness and width directions, which ensures consistent damping effect perpendicular to the optical axis and provides good damping performance.

[0044] In this embodiment, the drive coil assembly 4 includes a first coil group 421 and a second coil group 422 spaced apart. The first coil group 421 is arranged along one diagonal of the circuit board assembly 3, and the second coil group 422 is arranged along the other diagonal of the circuit board assembly 3. The magnet assembly 5 includes a first magnet unit 51 spaced apart from the first coil group 421 and a second magnet unit 52 spaced apart from the second coil group 422. The first magnet unit 51 is a Heilbeck magnetic circuit. The first coil group 421 interacts with the first magnet unit 51 to drive the circuit board assembly 3, which carries the image sensor 10, to move along a first direction X. The second coil group 422 interacts with the second magnet unit 52 to drive the circuit board assembly 3, which carries the image sensor 10, to move along a second direction Y.

[0045] In this embodiment, the first coil group 421 and the second coil group 422 are respectively disposed at the four corners of the circuit board assembly 3, so that the first magnet unit 51 and the second magnet unit 52 also correspond to the four corners of the circuit board assembly 3. The arrangement of multiple coils and multiple magnets improves the overall driving force of the lens driving device 100, while saving installation space.

[0046] In this embodiment, the lens driving device 100 further includes a first driving chip 11 and a second driving chip 12. The first driving chip 11 is disposed in the first coil group 421 and is used to control the first coil group 421 to interact with the magnet assembly 5 to move along the first direction X. The second driving chip 12 is disposed in the second coil group 422 and is used to control the second coil group 422 to interact with the magnet assembly 5 to move along the second direction Y.

[0047] In this embodiment, the lens driving device 100 further includes a first magnetic conductive sheet 6, which is stacked and fixed on the side of the magnet assembly 5 away from the driving coil assembly 4; the housing has a through-hole 1026, and the first magnetic conductive sheet is disposed in the through-hole 1026. The first magnetic conductive sheet 6 enhances the magnetic conductivity of the magnet assembly 5.

[0048] In this embodiment, the lens driving device 100 further includes a second magnetic conductive sheet 7, which is fixed to the housing 1. The second magnetic conductive sheet 7 is located on the side of the driving coil assembly 4 away from the magnet assembly 5, and is positioned directly opposite the magnet assembly 5. This enhances the magnetic conductivity.

[0049] In this embodiment, the first circuit board 31 is provided with a through hole 311 extending through it along the optical axis. The lens driving device 100 also includes a sensor bracket 14 fixed to the first circuit board 31. The sensor bracket 14 is fixed to the first circuit board 31 and covers the through hole 311. The image sensor 10 is fixed to the side of the sensor bracket 14 facing the opening 1025 and located inside the through hole 311.

[0050] Compared with the prior art, in the lens driving device of this utility model, the driving coil assembly and the magnet assembly are respectively fixed on the circuit board assembly and the housing. The driving coil assembly and the magnet assembly are spaced apart. The housing has an opening that runs through it along the optical axis of the image sensor. The image sensor is arranged opposite to the opening along the optical axis. The magnet assembly and the driving coil assembly are arranged opposite to each other along the optical axis to drive the image sensor to move relative to the housing in a direction perpendicular to the optical axis. The circuit board assembly includes a first circuit board stacked and fixed on one side of an elastic bracket and a second circuit board connected to the first circuit board. The driving coil assembly is fixed on the side of the first circuit board facing the magnet assembly. The second circuit board electrically connects the first circuit board to an external circuit. The first circuit board is a PCB circuit board, and the second circuit board is an FPC circuit board. By combining the first circuit board and the second circuit board, the stacking height of the circuit board assembly is further reduced. The first circuit board and the second circuit board are formed as a single structure, reducing the soldering between the first circuit board and the second circuit board, which can save the necessary stacking height along the optical axis during soldering, thereby reducing the overall stacking height and making the best use of the installation space.

[0051] The above description is merely an embodiment of this utility model. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of this utility model, but these improvements all fall within the protection scope of this utility model.

Claims

1. A lens driving device, comprising a housing, a magnet assembly fixed to the housing, a circuit board assembly suspended within the housing, an elastic bracket supporting the circuit board assembly on the housing, a drive coil assembly stacked and fixed to the circuit board assembly and electrically connected to the circuit board assembly, and an image sensor fixed to the circuit board assembly; the housing has an opening extending through it along the optical axis of the image sensor, and the image sensor is disposed opposite to the opening along the optical axis; the magnet assembly and the drive coil assembly are disposed opposite to each other along the optical axis to drive the image sensor to move relative to the housing in a direction perpendicular to the optical axis; characterized in that, The circuit board assembly includes a first circuit board stacked and fixed to the elastic bracket and a second circuit board connected to the first circuit board; the drive coil assembly is fixed to the side of the first circuit board facing the magnet assembly; the second circuit board electrically connects the first circuit board to an external circuit. The first circuit board is a PCB circuit board, and the second circuit board is an FPC circuit board. The first circuit board and the second circuit board are integrally formed.

2. The lens driving device according to claim 1, characterized in that, The thickness of the first circuit board is greater than the thickness of the second circuit board.

3. The lens driving device according to claim 1, characterized in that, The second circuit board includes a circuit board body, a flexible extension portion formed by extending the circuit board body away from the first circuit board, a connecting portion formed by bending and extending the circuit board body from opposite ends toward the first circuit board, and a fixing portion formed by bending and extending the connecting portion toward the first circuit board; the circuit board body is spaced apart from the first circuit board, and the fixing portion is fixed to the first circuit board. The housing has a clearance groove formed through one side perpendicular to the optical axis, and the flexible extension passes through the clearance groove to be electrically connected to an external circuit.

4. The lens driving device according to claim 1, characterized in that, The drive coil assembly includes a coil substrate stacked and fixed to the first circuit board and a drive coil fixed to the side of the coil substrate facing the magnet assembly.

5. The lens driving device according to claim 1, characterized in that, The magnet assembly interacts with the drive coil assembly to drive the image sensor to move along a first direction and a second direction perpendicular to the optical axis, the first direction being perpendicular to the second direction; the lens driving device further includes an anti-collision assembly fixed to the first circuit board; the anti-collision assembly includes a first anti-collision block fixed to opposite sides of the first circuit board along the first direction, and a second anti-collision block fixed to opposite sides of the first circuit board along the second direction.

6. The lens driving device according to claim 5, characterized in that, The lens driving device also includes a connector, with the first anti-collision block and the second anti-collision block fixed at both ends of the connector, respectively.

7. The lens driving device according to claim 6, characterized in that, The housing includes a bottom cover and an upper cover fixed to the bottom cover; the elastic bracket includes a bracket body disposed inside the upper cover, a first mounting portion and a second mounting portion extending from both ends of the bracket body toward the side close to the circuit board assembly; the circuit board assembly is fixed to the first mounting portion, the second mounting portion is fixed to the bottom cover, and the magnet assembly is fixed to the upper cover.

8. The lens driving device according to claim 7, characterized in that, The first anti-collision block is provided with a first limiting groove formed by recessing from the side of it close to the top cover to the side away from the top cover, and the second anti-collision block is provided with a second limiting groove formed by recessing from the side of it close to the top cover to the side away from the top cover. The upper cover includes a rectangular upper cover body, a support portion extending from one end of the upper cover body away from the bottom cover, the support portion forming the opening, and the upper cover also includes a first damping portion and a second damping portion extending from the inner edge of the support portion toward the bottom cover by bending. The first damping part extends into the first limiting groove, and the second damping part extends into the second limiting groove.

9. The lens driving device according to claim 8, characterized in that, The width of the first damping part parallel to the first direction is the same as the width parallel to the second direction; the width of the second damping part parallel to the first direction is the same as the width parallel to the second direction.

10. The lens driving device according to claim 1, characterized in that, The first circuit board has a through hole extending through it along the optical axis. The lens driving device also includes a sensor bracket fixed to the first circuit board. The sensor bracket is fixed to the first circuit board and covers the through hole. The image sensor is fixed to the side of the sensor bracket facing the opening and located inside the through hole.

Images