Lens driving device

Abstract

The present invention discloses a lens driving device, which includes a housing, a frame, a carrier, a base, an upper spring piece and a lower spring piece. The frame is provided with a magnet group, the carrier is provided with a first coil that cooperates with the magnet group, the base is provided with a second coil that cooperates with the magnet group. The first coil cooperates with the magnet group to drive the carrier to move along the optical axis direction, the second coil cooperates with the magnet group to drive the frame and the carrier to move in a plane perpendicular to the optical axis. And an elastic member is provided between the frame and the housing, and the elastic member is arranged around the frame. The elastic member includes a rectangular frame body and a frame connection part and a housing connection part arranged at the top of the rectangular frame body. The frame connection part and the housing connection part are respectively fixedly connected to the frame and the housing.

Description

Technical Field

[0001] The present invention relates to the field of optics, and in particular to a lens driving device. Background Art

[0002] With the widespread popularity of smart phones, the application scope of mobile phone cameras is getting wider and wider. However, most of the sensors of mobile phone cameras are currently placed in the module outside the motor. The side FPC uses a flexible circuit board, which causes problems such as warping, and the sensor detection is unstable. At the same time, the side FPC uses a flexible circuit board, and the uneven installation will affect the actual movement stroke. The vertical moving part of the middle carrier transmits the power of the bottom FPC to the upper spring sheet and then to the coil on the carrier through the suspension wire. When the motor is impacted or after a long period of operation, the reliability of the suspension wire becomes low, and it is easy to break and cause problems such as failure of the entire motor. In addition, the carrier is usually elastically connected to the frame and the base through the upper spring sheet and the lower spring sheet. During the movement of the carrier, the restoring force provided by the upper spring sheet and the lower spring sheet is insufficient, which easily makes the reset process of the carrier insensitive, affecting the imaging quality. Summary of the invention

[0003] The object of the present invention is to provide a lens driving device and an elastic member of the lens driving device to solve the above problems in the prior art.

[0004] In order to solve the above problems, according to one aspect of the present invention, a lens driving device is provided, which includes a shell, a frame, a carrier, a base, an upper spring leaf and a lower spring leaf, the frame is provided with a magnet group, the carrier is provided with a first coil cooperating with the magnet group, the base is provided with a second coil cooperating with the magnet group, the first coil cooperates with the magnet group to drive the carrier to move along the optical axis, the second coil cooperates with the magnet group to drive the frame and the carrier to move on a plane perpendicular to the optical axis, and an elastic member is provided between the frame and the shell, the elastic member is arranged around the frame, wherein the elastic member includes a rectangular frame main body and a frame connecting part and a shell connecting part arranged on the top of the rectangular frame main body, the frame connecting part and the shell connecting part are fixedly connected to the frame and the shell respectively.

[0005] In one embodiment, an elastic give way groove is provided at the bottom of the shell connecting part and the frame connecting part, and an avoidance groove cooperating with the elastic give way groove is provided on the side of the frame. When the elastic part is installed on the frame, the avoidance groove corresponds to the elastic give way groove.

[0006] In one embodiment, the upper spring piece forms an integral structure and includes an inner ring fixedly connected to the carrier, a frame fixing portion fixedly connected to the frame, and an upper spring piece elastic strip elastically connecting the inner ring and the frame fixing portion. The frame fixing portion cooperates with the four end corners of the frame and is fixedly connected between the upper surface of the magnet group and the lower surface of the frame.

[0007] In one embodiment, the lower spring piece is composed of four independent parts and respectively includes a first connecting piece, a second connecting piece, and a third connecting piece. The first connecting piece, the second connecting piece, and the third connecting piece are connected by a lower spring piece elastic strip and are respectively fixedly connected to the frame, the carrier, and the base.

[0008] In one embodiment, the bottom end of the frame is provided with a frame mounting protrusion, the lower surface of the carrier is provided with a carrier mounting protrusion, the upper surface of the base is provided with a base mounting protrusion, and the first connecting piece, the second connecting piece, and the third connecting piece of the lower spring piece are respectively fixed on the frame mounting protrusion, the carrier mounting protrusion, and the base mounting protrusion.

[0009] In one embodiment, a magnet avoidance space is formed between the lower spring piece elastic strip connecting the first connecting piece and the second connecting piece of the lower spring piece and the lower spring piece elastic strip connecting the second connecting piece and the third connecting piece, for the avoidance between the second coil and the magnet group.

[0010] In one embodiment, the housing includes a top and a side portion. The top is formed with a round hole for cooperating with the lens, and welding protrusions are provided on the inner side wall of the top. A baking avoidance groove is provided on the periphery of the round hole.

[0011] In one embodiment, the housing connecting portion forms a housing connecting piece and is connected to the inner wall of the top end of the housing by welding, and the frame connecting portion forms a frame connecting piece and is connected to the inner wall of the top end of the frame by welding.

[0012] In one embodiment, a bending portion is provided between the frame connecting piece and the housing connecting piece and the side portion of the elastic member.

[0013] In one embodiment, corners are formed between every two side portions of the rectangular frame body, and hollow portions are provided at the four corners of the rectangular frame body.

[0014] According to another aspect of the present invention, there is also provided an elastic member for a lens driving device. The lens driving device includes a housing and a frame. The elastic member is disposed between the frame and the housing and is arranged around the frame. The elastic member includes a rectangular frame body and a frame connection portion and a housing connection portion provided at the top of the rectangular frame body. The frame connection portion and the housing connection portion are fixedly connected to the frame and the housing respectively.

[0015] In one embodiment, the frame connection portion forms a frame connection piece and is connected to the inner wall of the top end of the frame by welding.

[0016] In one embodiment, the housing connection portion forms a housing connection piece and is connected to the inner wall of the top end of the housing by welding.

[0017] In one embodiment, a bending portion is provided between the frame connection piece and the housing connection piece and the side portion of the elastic member.

[0018] In one embodiment, the bending portion realizes the three-dimensional structure of the elastic member through multi-stage bending.

[0019] In one embodiment, a corner portion is formed between every two adjacent side portions of the rectangular frame body, and hollow portions are provided at the four corner portions of the rectangular frame body.

[0020] In one embodiment, elastic relief grooves are provided at the bottoms of the housing connection portion and the frame connection portion to increase the elastic deformation amount of the elastic member when moving in a plane perpendicular to the optical axis.

[0021] In one embodiment, a protrusion is provided on the outer side of the housing connection portion to increase the welding area between the housing connection portion and the housing.

[0022] In one embodiment, the frame connection portion is provided at the top of one pair of opposite side portions of the rectangular frame body, and the housing connection portion is provided at the top of the other pair of opposite side portions of the rectangular frame body.

[0023] In one embodiment, the frame connection portion and the housing connection portion are respectively provided at the middle positions of the side portions where they are located.

[0024] The lens driving device of the present invention can solve the problem that the reset ability of the carrier of the traditional optical element driving device is not strong after displacement, and improve the optical anti-shake performance of the optical element driving device. Description of the Drawings

[0025] Figure 1 is an exploded perspective view of a lens driving device according to an embodiment of the present invention.

[0026] Figure 2It is a perspective view of an elastic member according to an embodiment of the present invention.

[0027] Figure 3 It is a perspective view of a frame according to an embodiment of the present invention.

[0028] Figure 4 and Figure 5 are respectively perspective views of the upper spring piece and the lower spring piece according to an embodiment of the present invention

[0029] Figure 6 and Figure 7 are respectively different perspective views of some components of a lens driving mechanism according to an embodiment of the present invention after being assembled.

[0030] Figure 8 It is a perspective view of a lens driving device according to an embodiment of the present invention.

[0031] Figure 9 It is a perspective view of the base of a lens driving device according to an embodiment of the present invention.

[0032] Figure 10 It is a perspective view of the housing of a lens driving device according to an embodiment of the present invention. Detailed Description of the Embodiment

[0033] The following will describe the preferred embodiments of the present invention in detail with reference to the accompanying drawings so as to more clearly understand the purpose, features and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not limitations on the scope of the present invention, but only to illustrate the essential spirit of the technical solution of the present invention.

[0034] In the following description, certain specific details are set forth in order to provide a thorough understanding of various disclosed embodiments. However, one or more of these specific details may be practiced without these specific details. In other instances, well-known devices, structures and techniques associated with the present application may not be shown or described in detail so as not to unnecessarily obscure the description of the embodiments.

[0035] References to "one embodiment" or "an embodiment" throughout the specification mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of "in one embodiment" or "in an embodiment" throughout the specification are not necessarily all referring to the same embodiment. Additionally, the particular features, structures, or characteristics may be combined in any manner in one or more embodiments.

[0036] In the following description, in order to clearly show the structure and working mode of the present invention, many directional terms will be used for description. However, words such as "front", "rear", "left", "right", "outer", "inner", "outward", "inward", "up", and "down" should be understood as convenient terms and should not be understood as limiting terms.

[0037] Figure 1 is an exploded perspective view of a lens driving device according to an embodiment of the present invention. As Figure 1 shown, the lens driving device 100 includes a housing 10, a frame 20, a carrier 30, a base 40, an upper spring piece 50, and a lower spring piece 60. Among them, the frame 20 is provided with a magnet group 21, the carrier 30 is provided with a first coil 31 that cooperates with the magnet group 20, the base 40 is provided with a second coil 41 that cooperates with the magnet group 21, the first coil 31 cooperates with the magnet group 21 to drive the carrier 30 to move along the optical axis direction, the second coil 41 cooperates with the magnet group 21 to drive the frame 20 and the carrier 30 to move in a plane perpendicular to the optical axis, and an elastic member 70 is provided between the frame 20 and the housing 10, and the elastic member 70 is used to realize the reset action of the frame 20 and the carrier 30. It should be noted that the magnet group 21 of the present invention is provided on the frame 20 and is used for cooperation with the first coil 31 and the second coil 41 at the same time. However, those skilled in the art can understand that different magnet groups can also be respectively provided for cooperation with the first coil and the second coil. For example, a first magnet group is provided for cooperation with the first coil 31, and a second magnet group is provided for cooperation with the second coil 41. By adding the elastic member 70 for the reset operation after the translation of the frame and the carrier, the present invention has higher anti-shake performance compared with the traditional lens driving device that only relies on the upper and lower spring pieces for reset, and can achieve higher-quality imaging effects.

[0038] Specifically, Figure 2 is a perspective view of the elastic member 70 according to an embodiment of the present invention. As Figure 2 shown, the elastic member 70 integrally forms a rectangular frame structure and is arranged around the frame 20. The elastic member 70 includes a rectangular frame main body 71 and a frame connection part 72 and a housing connection part 73 provided at the top of the rectangular frame main body 71. Preferably, the frame connection part 72 is provided at the top of one pair of opposite sides of the rectangular frame main body 71, and the housing connection part 73 is provided at the top of the other pair of opposite sides of the rectangular frame main body 71. Preferably, the frame connection part 72 and the housing connection part 73 are respectively provided at the middle positions of the respective sides where they are located. That is to say, the frame connection part 72 and the housing connection part 73 divide the respective sides where they are located into two substantially equal parts, and the sides where they are located are substantially axially symmetrically arranged with respect to the frame connection part 72 or the housing connection part 73.

[0039] In one embodiment, the frame connection portion 72 forms a frame connection piece and is connected to the top end of the frame 20 by welding. Optionally, the housing connection portion 73 forms a housing connection piece and is connected to the inner wall of the top end of the housing 10 by welding. Optionally, a bending portion 74 is provided between the frame connection piece and the housing connection piece and the side portion of the elastic member 70. The bending portion 74 realizes the three-dimensional structure of the elastic member 70 through multi-stage bending and avoids metal fatigue caused by a one-time 90-degree bending.

[0040] In one embodiment, a corner portion is formed between every two side portions of the rectangular frame body 71. Optionally, hollow portions 75 are provided at the four corner portions of the rectangular frame body 71, which can increase the elastic deformation amount of the elastic member 70 moving in a plane perpendicular to the optical axis.

[0041] Optionally, elastic yielding grooves 76 are provided at the bottoms of the housing connection portion 72 and the frame connection portion 73, which are used to increase the elastic deformation amount of the elastic member 70 moving in a plane perpendicular to the optical axis.

[0042] Optionally, a protrusion portion 731 is provided on the outer side of the housing connection portion 73, which can increase the welding area between the housing connection portion 73 and the housing and enhance the connection stability.

[0043] Figure 3 is a perspective view of the frame 20 of an embodiment of the present invention. As Figure 3 shown, in one embodiment, the frame 20 forms a rectangular frame structure. The magnet group 21 includes four magnets and is respectively arranged at the four end corners of the frame 20. Optionally, magnet grooves 23 are provided at the four end corners of the frame 20. The magnet grooves 23 are used to install magnets. A frame top plate 24 is provided at the top of the magnet grooves 23. The frame fixing portion 52 of the upper spring piece 50 is arranged between the top of the magnet and the frame top plate 24. The inner ring of the upper spring piece 50 is connected to the top end of the carrier. Among them, the magnet group 21 is fixedly installed on the frame 20. That is to say, the magnet group 21 and the frame 20 form an integral body. When the magnet group 21 moves, the frame 20 also moves accordingly.

[0044] In one embodiment, an avoidance groove 25 that cooperates with the elastic yielding groove 76 of the elastic member 70 is provided on the side portion of the frame 20. When the elastic member 70 is installed on the frame 20, the avoidance groove 25 corresponds to the elastic yielding groove 76.

[0045] Figure 4 and Figure 5 are perspective views of the upper spring piece and the lower spring piece of an embodiment of the present invention respectively. As Figure 4-5As shown, in one embodiment, the upper spring piece 50 is integrally formed as a single structure and includes an inner ring 51 fixedly connected to the carrier 30, a frame fixing portion 52 fixedly connected to the frame 30, and an upper spring piece elastic strip 53 elastically connecting the inner ring 51 and the frame fixing portion 52. In one embodiment, the frame fixing portion 52 cooperates with the four end corners of the frame 20 and is preferably fixedly connected between the upper surface of the magnet group 21 and the lower surface of the frame 20. When the first coil 31 is energized, an electromagnetic induction is formed with the magnet group 21, and the magnet group 21 is driven to drive the frame 20 to move along the optical axis direction, thereby realizing the optical zoom function. During the movement of the frame 20, since the frame 20 is connected to the carrier 30 through the upper spring piece 50, the upper spring piece elastic strip 53 of the upper spring piece 50 will be stretched and deformed. Thus, when the frame 20 moves to a certain extent, the upper spring piece elastic strip 53 will generate a restoring force to drive the frame 20 back to its original position, and the frame 20 is driven back to its original position by this restoring force.

[0046] Optionally, the lower spring piece 60 is integrally composed of four independent parts, and the structure and shape of each part are similar. Only one of them will be taken as an example for illustration below. For the sake of simplicity in description, this part will be collectively referred to as the lower spring piece hereinafter. Referring to Figure 3 and Figure 5 , the lower spring piece 60 is disposed on the base 40 and includes a first connecting piece 61, a second connecting piece 62, and a third connecting piece 63. The first connecting piece 61, the second connecting piece 62, and the third connecting piece 63 are elastically connected by a lower spring piece elastic strip 64 and are respectively fixedly connected to the frame 20, the carrier 30, and the base 40. The lower spring piece 60 not only serves to reset the carrier 30 and the frame 20, but also serves to connect the built-in circuit of the base to the built-in circuit of the carrier.

[0047] Figure 6-7 are respectively the perspective views of some components of the lens driving mechanism according to an embodiment of the present invention after being assembled. As shown in Figure 3 and Figure 6-7 , in one embodiment, a frame mounting protrusion 22 is provided at the bottom end of the frame 20. Optionally, the frame mounting protrusion 22 is disposed adjacent to the avoidance groove 25. A carrier mounting protrusion 32 is provided on the lower surface of the carrier 30, and a base mounting protrusion 43 is provided on the upper surface of the base 40. The first connecting piece 61, the second connecting piece 62, and the third connecting piece 63 of the lower spring piece 60 are respectively fixed to the frame mounting protrusion 22 of the frame 20, the carrier mounting protrusion 32 of the carrier 30, and the base mounting protrusion 43 of the base 40, for example, by welding. The upper spring piece 60 not only serves to reset the carrier 30 and the frame 20, but also serves to connect the built-in circuit of the base to the built-in circuit of the carrier, which will be further described below.

[0048] Optionally, a magnet avoidance space is formed between the lower spring elastic strip connecting the first connecting piece 61 and the second connecting piece 62 of the lower spring piece 60 and the lower spring elastic strip connecting the second connecting piece 62 and the third connecting piece 63, for the avoidance between the built-in coil in the base and the magnet group.

[0049] Figure 8 is a perspective view of a lens driving device according to an embodiment of the present invention. Figure 9 is a perspective view of the base of a lens driving device according to an embodiment of the present invention. As Figure 8-9 shown, in one embodiment, the second coil 41 is built into the inner sides of the four corners of the base 40 to form a built-in coil, the built-in coil is arranged corresponding to the magnet group 21, the built-in coil is communicated with the built-in circuit of the base, when the carrier moves in a plane perpendicular to the optical axis, the force between the energized built-in coil and the magnet makes the magnet perform a planar movement, thereby driving the frame and the carrier to perform a planar movement, and the lower spring piece and the elastic member are used for the reset operation of the frame and the carrier.

[0050] Continue to refer to Figure 8-9 , a sensor mounting groove 44 is provided at the bottom end of the base 40 for placing two position sensors 45, the position sensors 45 correspond to the magnet group 21, and the two position sensors 45 are respectively used to detect the moving distances of the magnet on the X-axis and Y-axis in a plane perpendicular to the optical axis, so as to monitor the carrier and then detect the position of the lens according to the movement position of the magnet. Optionally, circuit pins 46 are provided on the base 40 for connecting the built-in circuit of the base to an external circuit.

[0051] Figure 10 is a perspective view of the housing 10 of a lens driving device according to an embodiment of the present invention. As Figure 10 shown, the housing 10 includes a top and a side, a round hole for cooperating with the lens is formed in the top and welding protrusions 12 are provided on the inner sidewall, and a baking avoidance groove 13 is further provided at the periphery of the round hole. The welding protrusions 12 are used for welding with the upper end surface of the housing connecting portion of the elastic member 70, and the baking avoidance groove 13 is used for baking dry the glue between the lower end surface of the frame connecting portion and the upper end surface of the frame of the elastic member 70, so as to facilitate the overall installation work.

[0052] During assembly, the base 40 is provided with a lower reed 60. Above the lower reed 60, the frame 20 and the carrier 30 are connected. The frame 20 is sleeved outside the carrier 30. A magnet group 21 is provided between the inner side wall of the frame and the outer side wall of the carrier. An upper reed 50 is provided between the top of the magnet and the carrier. The carrier 30 is sleeved with a first coil 31. When performing longitudinal movement, the built-in circuit in the base 40 transmits current to the first coil 31 through the lower reed 60 and the built-in circuit of the carrier. After the first coil 31 is powered on, an Ampere force is generated between the first coil 31 and the magnet group 21 to perform the longitudinal movement operation. The upper reed 50 and the lower reed 60 are used for the reset operation of the carrier 30. An elastic member 70 is provided between the outer side of the frame and the inner side wall of the housing. When the carrier performs planar movement perpendicular to the optical axis direction, the force between the built-in coil (i.e., the second coil 41) on the base 40 and the magnet group 21 after being powered on causes the magnet to perform planar movement, thereby driving the frame and the carrier to perform planar movement. The lower reed and the elastic member 70 are used for the reset operation of the frame and the carrier.

[0053] In summary, the optical element driving device of the present invention has a broad commercial use scenario and can be widely applied to various electronic devices such as mobile phones and smart phones.

[0054] The preferred embodiments of the present invention have been described in detail above. However, it should be understood that after reading the above teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention. These equivalent forms also fall within the scope defined by the appended claims of this application.

Claims

1. A lens driving device, characterized in that, the lens driving device includes a housing, a frame, a carrier, a base, an upper spring piece and a lower spring piece. The frame is provided with a magnet group, the carrier is provided with a first coil cooperating with the magnet group, the base is provided with a second coil cooperating with the magnet group, the first coil cooperates with the magnet group to drive the carrier to move along the optical axis direction, the second coil cooperates with the magnet group to drive the frame and the carrier to move in a plane perpendicular to the optical axis, and an elastic member is provided between the frame and the housing, the elastic member is arranged around the frame, wherein the elastic member includes a rectangular frame body and a frame connection part and a housing connection part arranged at the top of the rectangular frame body, and the frame connection part and the housing connection part are respectively fixedly connected to the frame and the housing; the housing connection part forms a housing connection piece and is connected to the inner wall of the top end of the housing by welding, and the frame connection part forms a frame connection piece and is connected to the inner wall of the top end of the frame by welding; a bending part is provided between the frame connection piece and the housing connection piece and the side part of the elastic member; corners are formed between every two side parts of the rectangular frame body, and hollow parts are provided at the four corners of the rectangular frame body; elastic relief grooves are provided at the bottoms of the housing connection part and the frame connection part.

2. The lens driving device according to claim 1, characterized in that, a relief groove cooperating with the elastic relief groove is provided on the side part of the frame. When the elastic member is installed on the frame, the relief groove corresponds to the elastic relief groove.

3. The lens driving device according to claim 1, characterized in that, the upper spring piece forms an integral structure and includes an inner ring fixedly connected to the carrier, a frame fixing part fixedly connected to the frame, and an upper spring piece elastic strip elastically connecting the inner ring and the frame fixing part. The frame fixing part cooperates with the four end corners of the frame and is fixedly connected between the upper surface of the magnet group and the lower surface of the frame.

4. The lens driving device according to claim 1, characterized in that, the lower spring piece is composed of four independent parts and respectively includes a first connection piece, a second connection piece and a third connection piece. The first connection piece, the second connection piece and the third connection piece are connected by a lower spring piece elastic strip and are respectively fixedly connected to the frame, the carrier and the base.

5. The lens driving device according to claim 4, characterized in that, a frame mounting protrusion is provided at the bottom end of the frame, a carrier mounting protrusion is provided on the lower surface of the carrier, a base mounting protrusion is provided on the upper surface of the base, and the first connection piece, the second connection piece and the third connection piece of the lower spring piece are respectively fixed on the frame mounting protrusion, the carrier mounting protrusion and the base mounting protrusion.

6. The lens driving device according to claim 4, characterized in that, A magnet avoidance space is formed between the lower spring strip elastic strips connecting the first connecting strip and the second connecting strip and the lower spring strip elastic strips connecting the second connecting strip and the third connecting strip of the lower spring strip, for avoiding between the second coil and the magnet group.

7. The lens driving device according to claim 1, characterized in that the housing includes a top and a side, a round hole for cooperating with the lens is formed in the top, welding protrusions are provided on the inner side wall of the top, and a baking avoidance groove is provided on the periphery of the round hole.

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