Lens drive unit

Abstract

The present invention provides a lens driving device. 【Solution means】 It includes a base, a support frame, a lens barrel holder, an elastic assembly, a shake correction coil, and a magnet steel. A central hole penetrating it is provided at the center of the base. The elastic assembly is fixed to both opposite sides of the support frame in the optical axis direction. The shake correction coil is fixed to the base. The magnet steel is fixed to the support frame and faces the shake correction coil with a gap therebetween. The shake correction coil drives the lens barrel holder to move synchronously. The shake correction coil cooperates with the magnet steel to drive the support frame to move along a direction perpendicular to the optical axis of the lens barrel holder. The shake correction coil is in a ring shape, and an arc-shaped structure that bends and recesses in a direction away from the central hole is provided on the side of the shake correction coil close to the central hole. The arc-shaped structure matches the outer peripheral shape of the central hole so that the shake correction coil is completely located outside the range of the central hole. Compared with the prior art, the lens driving device of the present invention has a good shake correction effect, saves mounting space, and provides a good user experience.

Description

[Technical Field]

[0001] The present invention relates to a driving device, and more particularly to a lens driving device. [Background technology]

[0002] With the development of imaging technology, lens drivers have been widely applied to various imaging devices, and the combination of lens drivers with various portable electronic devices such as mobile phones, video cameras, and personal computers has become popular among consumers.

[0003] In conventional lens drive devices, the drive mechanism typically combines a coil and a magnetic steel to form a drive structure, with a support frame supported on a base, a lens barrel holder mounted in a center hole of the base, a drive coil and a drive magnetic steel fixed to the lens barrel holder and support frame, respectively, an OIS coil (image stabilization coil) fixed to a housing and located above the support frame, and an image stabilization magnetic steel fixed to the side of the support frame away from the base. When a current is applied to the image stabilization coil, an electromagnetic field is generated in the image stabilization coil and the image stabilization magnetic steel, and the image stabilization coil is subjected to the Lorentz force of the electromagnetic field, driving the image stabilization magnetic steel to move in a direction perpendicular to the optical axis, thereby driving the lens barrel and achieving the image stabilization function.

[0004] However, in the lens driving device of the prior art, one side of the image stabilization coil is close to the center hole of the base, so the image stabilization coil is prone to exceeding the center hole due to deformation or assembly tolerances, taking up installation space and making the overall assembly difficult.

[0005] Therefore, it is necessary to provide a new lens driving device that solves the above problems. Summary of the Invention [Problem to be solved by the invention]

[0006] The technical problem to be solved by the present invention is to provide a lens driving device that is small, easy to assemble, and requires less installation space. [Means for solving the problem]

[0007] In order to solve the above technical problems, the present invention provides a lens driving device, which includes a base, a support frame, a lens barrel holder, an elastic assembly, an image stabilization coil, and a magnet steel. The base has a center hole penetrating the center of the base. The support frame has an accommodation space, and the support frame is installed facing the base and spaced apart. The lens barrel holder is accommodated in the accommodation space and spaced apart from the support frame, and is used to mount a lens module. The elastic assemblies are fixed to opposite sides of the support frame in the optical axis direction and elastically suspend the lens barrel holder in the accommodation space. the image stabilization coil is fixed to the base, the magnetic steel is fixed to the support frame and faces the image stabilization coil with a gap between them, the image stabilization coil cooperates with the magnetic steel to drive the support frame to move in a direction perpendicular to the optical axis of the lens barrel holder so as to drive the lens barrel holder to move synchronously, the image stabilization coil is ring-shaped, and the side of the image stabilization coil closest to the center hole is provided with an arc-shaped structure that is bent and concave in a direction away from the center hole, and the arc-shaped structure matches the outer peripheral shape of the center hole so that the image stabilization coil is positioned completely outside the range of the center hole.

[0008] Preferably, the image stabilization coil has a track shape and includes two long sides arranged opposite to each other and two short sides arranged opposite to each other, and the arc-shaped structure is provided on the long sides that are closer to the center hole.

[0009] Preferably, the base has a rectangular structure, the four image stabilization coils are arranged to surround the central hole and are fixed to the four sides of the base, the four image stabilization coils are parallel to the four sides of the base, and the four magnetic steel pieces are arranged to be fixed to the support frame, with the four image stabilization coils corresponding one-to-one to the four magnetic steel pieces.

[0010] Preferably, the lens driving device further includes a flexible substrate for connection to an external power source, the flexible substrate being fixed to the side of the base closer to the magnetic steel, and the image stabilization coil being laminated and fixed to the flexible substrate and electrically connected to the flexible substrate.

[0011] Preferably, the elastic assembly comprises an upper elastic sheet and a lower elastic sheet, the upper elastic sheet comprising a first fixed arm fixed to the support frame, a second fixed arm fixed to the lens barrel holder, and a plurality of first elastic arms connecting the first fixed arm and the second fixed arm, the first elastic arm being installed at a distance from the support frame along the optical axis direction of the lens barrel holder, and the lower elastic sheet comprising a third fixed arm fixed to the side of the support frame closer to the base, a fourth fixed arm fixed to the lens barrel holder, and a second elastic arm connecting the third fixed arm and the fourth fixed arm, the second elastic arm being installed at a distance from the support frame along the optical axis direction of the lens barrel holder.

[0012] Preferably, the lens driving device further includes suspension wires, the suspension wires being plural and spaced apart, with both ends of each suspension wire fixed to the base and the support frame, respectively, so as to suspend the support frame from the base.

[0013] Preferably, the lens driving device further includes a horizontal support elastic member, the horizontal support elastic member including a first arm fixed to the suspension wire, a second arm fixed to the support frame, and an elastic arm connecting the first arm and the second arm.

[0014] Preferably, the support frame comprises a rectangular frame body and four fixed structures located at the four corners of the support frame, the upper elastic sheets are two in number and are installed opposite each other at a distance, each upper elastic sheet has two first elastic arms spaced apart from each other, the four first fixed arms correspond one-to-one to the four fixed structures, and the magnetic steel is fixed to the side of the frame body closer to the lens barrel holder.

[0015] Preferably, the base has a rectangular structure, there are four image stabilization coils, and they are fixed to the four sides of the base, and there are four magnetic steel pieces, and they are fixed to the support frame, and the four image stabilization coils are provided in one-to-one correspondence with the four magnetic steel pieces.

[0016] Preferably, the lens driving device further includes a focus coil, which is fixedly fitted to the lens barrel holder and installed at a distance from the magnetic steel, and the focus coil and the magnetic steel work together to drive the lens barrel holder to move along the optical axis direction, thereby realizing an autofocus function.

[0017] Preferably, the flexible substrate further includes a substrate body fixed to the base, and a pin that bends and extends from one side of the substrate body to the base. [Effects of the Invention]

[0018] Compared to the prior art, the lens driver of the present invention has an arc-shaped structure on the side of the image stabilization coil closest to the center hole, which is concave and bent away from the center hole. This arc-shaped structure matches the outer shape of the center hole, ensuring that the image stabilization coil is positioned completely outside the center hole. By providing a concave structure in the middle portion of the image stabilization coil closest to the center hole in this manner, the image stabilization coil can be prevented from exceeding the center hole while maintaining its dimensional driving force. This allows for full utilization of product space, miniaturization of the entire lens driver, and a better user experience. [Brief explanation of the drawings]

[0019] In order to more clearly explain the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings that need to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work, among which: [Figure 1] FIG. 1 is a diagram showing the three-dimensional structure of a lens driving device according to the present invention. [Figure 2] FIG. 2 is a diagram showing the overall exploded structure of the lens driving device of the present invention. [Figure 3] FIG. 3 is a cross-sectional view taken along the line AA in FIG. [Figure 4] FIG. 4 is a diagram showing the structure of the upper elastic sheet of the present invention. [Figure 5] FIG. 5 is a diagram showing the structure of the lower elastic sheet of the present invention. [Figure 6] FIG. 6 is a top view of the assembled base, flexible substrate, and image stabilization coil of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and are not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative ingenuity shall fall within the protection scope of the present invention. Example 1

[0021] As shown in Figures 1 to 6, there is provided a lens driving device 100 including a base 1, a support frame 2, a suspension wire 12, a housing 3, a lens barrel holder 4, an image stabilization coil 6, a magnetic steel 7, a focus coil 8, an elastic assembly 5, and a flexible substrate 10.

[0022] A central hole 14 is provided through the center of the base 1, and the central hole 14 makes it easy to install the lens barrel holder 4. The base 1 is used to support and fix the flexible substrate 10 and the image stabilization coil 6.

[0023] The support frame 2 has a storage space 9, and is installed facing the base 1 with a gap therebetween.

[0024] In this embodiment, the lens driving device 100 further includes a housing 3 that is provided to be covered by the base 1 and that, together with the base 1, surrounds a storage space 31, and suspension wires 12 that support the support frame 2 movably within the storage space 31, one end of the suspension wires 12 being connected to the base 1 and the other end being connected to the elastic assembly 5. The suspension wires 12 are made of a metallic conductive material and consist of a plurality of wires that are spaced apart from one another and are arranged around the support frame 2, with one end of each suspension wire 12 fixed to the base 1 and the other end being fixed to and electrically connected to the upper elastic sheet 51. The suspension wires 12 are used to provide a restoring force to the support frame 2 when the image stabilization function is in use.

[0025] The lens barrel holder 4 is accommodated in the accommodation space 9 and is used to mount a lens module having an optical axis (Z axis).

[0026] The elastic assemblies 5 are fixed to opposite sides of the support frame 2 in the optical axis direction, and elastically support the lens barrel holder 4 within the accommodation space 9. As a result, when a current is applied to the image stabilization coil 6, an electromagnetic field is generated between the image stabilization coil 6 and the magnetic steel 7, and the image stabilization coil 6 is subjected to the Lorentz force of the electromagnetic field, driving the magnetic steel 7 to move in a direction perpendicular to the optical axis, thereby driving the lens barrel and contributing to achieving OIS image stabilization performance.

[0027] The image stabilization coil 6 is fixed to the base 1. The image stabilization coil 6 is fixed to the base 1, and the magnetic steel 7 is fixed to the support frame 2 on the side closer to the lens barrel holder 4. The image stabilization coil 6 is located within the magnetic field range of the magnetic steel 7 and drives the magnetic steel 7 to move in a direction perpendicular to the optical axis. Here, the image stabilization coil 6 is formed by pre-winding, and the plane in which the winding direction of the image stabilization coil 6 lies is perpendicular to the optical axis direction. This allows for a significant reduction in costs.

[0028] The magnetic steel 7 is fixed to the support frame 2 and faces the image stabilization coil 6 at a distance, and the image stabilization coil 6 cooperates with the magnetic steel 7 to drive the support frame 2 to move in a direction perpendicular to the optical axis of the lens barrel holder 4 so as to drive the lens barrel holder 4 to move synchronously. The magnetic steel 7 includes first drive magnetic steel 7 fixed to opposite sides of the support frame 2 in the direction perpendicular to the optical axis, and second drive magnetic steel 7 fixed to opposite sides of the other side of the support frame 2, and each magnetic steel 7 is unipolar magnetized. A single magnetic pole is provided on each of the opposite sides of the magnetic steel 7.

[0029] The flexible substrate 10 is fixed to the base 1 and is used to connect to an external power source. The flexible substrate 10 is fixed to the side of the base 1 that is closer to the magnetic steel 7, and the image stabilization coil 6 is laminated and fixed to the flexible substrate 10 and electrically connected to the flexible substrate 10.

[0030] The image stabilization coil 6 is ring-shaped, and the side of the image stabilization coil 6 closest to the central hole 14 is provided with an arc-shaped structure 61 that is concave and bent away from the central hole 14. The arc-shaped structure 61 matches the outer shape of the central hole 14 so that the image stabilization coil 6 is positioned completely outside the range of the central hole 14. By forming the middle portion of the image stabilization coil 6 closest to the central hole 14 into the arc-shaped structure 61 in a predetermined shape, the dimensional driving force of the image stabilization coil can be maintained while not exceeding the central hole 14. This makes full use of the space in the product, allowing the entire lens driving device 100 to be made smaller, and improving the user experience.

[0031] Specifically, the lens driving device 100 further includes a focus coil 8, which is fixedly fitted around the lens barrel holder 4 and spaced apart from the magnet steel 7. The focus coil 8 and the magnet steel 7 work together to drive the lens barrel holder 4 to move along the optical axis direction, thereby achieving an autofocus function. The focus coil 8 is fixedly fitted around the outer periphery of the lens barrel holder 4 and spaced apart from the magnet steel 7. The focus coil 8 is electrically connected to the upper elastic sheet 51. The magnetization direction of the magnet steel 7 is parallel to the winding plane of the focus coil 8, and the focus coil 8 drives the focus coil 8 to move along the optical axis direction. By moving the lens barrel holder 4 along the optical axis direction using the focus coil 8, an autofocus (AF) function can be achieved. In this embodiment, the magnetization direction of the magnet steel 7 is parallel to the winding plane of the focus coil 8.

[0032] Of course, the magnetization direction of each magnet steel 7 may be perpendicular to the optical axis direction.

[0033] Here, the lens barrel holder 4 , focus coil 8 , image stabilization coil 6 , magnetic steel 7 and flexible substrate 10 are all housed within a housing 3 .

[0034] In this embodiment, the image stabilization coil 6 has a track shape, with two long sides 62 facing each other and two short sides 63 facing each other, and the arc-shaped structure 61 is provided on the long sides 62 that are closest to the center hole 14. This maximizes the use of product space, reduces the overall size of the lens driving device 100, and improves the user experience.

[0035] In this embodiment, the base 1 has a rectangular structure, and the four image stabilization coils 6 are arranged around the central hole 14 and fixed to the four sides of the base 1, respectively, and parallel to the four sides of the base 1. The four magnetic steel bars 7 are also arranged and fixed to the support frame 2, respectively, and each of the four image stabilization coils 6 corresponds to one of the four magnetic steel bars 7. By correspondingly arranging the multiple image stabilization coils 6 and the multiple magnetic steel bars 7, it is possible to adjust driving forces in different directions. For example, the first and second directions are driving directions that are perpendicular to each other on the same plane, where the first direction is the X-axis direction and the second direction is the Y-axis direction. Electrically connecting different image stabilization coils 6 enables image stabilization adjustment in different directions, which is convenient.

[0036] In this embodiment, the elastic assembly 5 includes an upper elastic sheet 51 and a lower elastic sheet 52. The upper elastic sheet 51 includes a first fixed arm 511 fixed to the support frame 2, a second fixed arm 512 fixed to the barrel holder 4, and a plurality of first elastic arms 513 connecting the first fixed arm 511 and the second fixed arm 512, the first elastic arms 513 being installed at a distance from the support frame 2 along the optical axis direction of the barrel holder 4. The lower elastic sheet 52 includes a third fixed arm 521 fixed to the side of the support frame 2 closer to the base 1, a fourth fixed arm 522 fixed to the barrel holder 4, and a second elastic arm 523 connecting the third fixed arm 521 and the fourth fixed arm 522, the second elastic arm 523 being installed at a distance from the support frame 2 along the optical axis direction of the barrel holder 4.

[0037] One end of the upper elastic sheet 51 is fixed to the upper end of the support frame 2 along the optical axis direction of the barrel holder 4, and the other end of the upper elastic sheet 51 is fixed to the upper end of the barrel holder 4 along the optical axis direction, thereby elastically suspending the barrel holder 4 within the accommodation space 9. In this embodiment, the upper elastic sheet 51 is provided with a conductive path for realizing the transmission of electrical signals. For example, if the upper elastic sheet 51 is an FPC, the conductive path is realized by a conductive line in the FPC.

[0038] The two upper elastic sheets 51 are provided insulated from each other and together form a ring-shaped surrounding, with each upper elastic sheet 51 forming one conductive path, thereby enabling the transmission of electrical signals at both positive and negative poles. In this embodiment, the two upper elastic sheets 51 are provided symmetrically with respect to the center of the lens barrel holder 4. Of course, the two upper elastic sheets 51 may be of an integral structure, as long as the two conductive paths are insulated from each other, which is easy to understand.

[0039] One end of the lower elastic sheet 52 is fixed to the bottom end of the support frame 2 along the optical axis direction, and the other end of the lower elastic sheet 52 is fixed to the bottom end of the lens barrel holder 4 along the optical axis direction, and the upper elastic sheet 51 and the lower elastic sheet 52 together elastically support the lens barrel holder 4 within the accommodation space 9. The lower elastic sheet is used to provide a restoring force to the lens barrel holder 4 when using the autofocus (AF) function.

[0040] In this embodiment, the lens driving device 100 further includes a horizontal support elastic member 13, which includes a first arm 131 fixed to the suspension wire 12, a second arm 132 fixed to the support frame 2, and an elastic arm 133 connecting the first arm 131 and the second arm 132. By fixing the two suspension wires 12 to the first arm 131 and the base 1, respectively, suspension of the base 1 and the support frame 2 can be achieved.

[0041] In this embodiment, the support frame 2 includes a rectangular frame body 21 and four fixing structures 22 located at the four corners of the support frame 2. Two upper elastic sheets 51 are provided, facing each other at a distance. Each upper elastic sheet 51 includes two first elastic arms 52 spaced apart from each other. The four first fixing arms 511 correspond one-to-one to the four fixing structures 22. The magnetic steel 7 is fixed to the frame body 21 on the side closer to the lens barrel holder 4. This facilitates fastening the upper elastic sheet 51 to the fixing structures 22, enhances the fixing effect of the lens barrel holder 4, and makes the lens barrel holder 4 more stable. Optionally, the first fixing arms 511 are provided with a plurality of mounting holes passing therethrough. The fixing structures 22 are a plurality of fixing posts corresponding to the mounting holes. The mounting holes are fitted onto the fixing posts, respectively, to form a fixed connection.

[0042] In this embodiment, the flexible substrate 10 further includes a substrate body 101 fixed to the base 1, and pins 102 that bend and extend from one side of the substrate body 101 to the base 1. The pins 102 contribute to connection with external signal lines.

[0043] Compared to the prior art, the lens driver of the present invention has an arc-shaped structure on the side of the image stabilization coil closest to the center hole that is concave and bent away from the center hole, and this arc-shaped structure matches the outer shape of the center hole, so that the image stabilization coil is positioned completely outside the center hole. By providing a concave structure in the middle portion of the image stabilization coil closest to the center hole in this predetermined shape, the image stabilization coil can be prevented from exceeding the center hole while maintaining its dimensional driving force. This makes full use of the product's space, reduces the overall size of the lens driver, and improves the user experience.

[0044] The above-described embodiments are merely examples of the present invention, and those skilled in the art may make modifications without departing from the creative idea of ​​the present invention, and it is to be noted that all such modifications fall within the scope of protection of the present invention.

Claims

1. The camera includes a base, a support frame, a lens barrel holder, an elastic assembly, a plurality of hollow image stabilization coils, and a magnet steel; The base has a central hole extending therethrough, the support frame has an accommodation space, and is installed facing the base with a gap therebetween; the lens barrel holder is accommodated in the accommodation space and spaced apart from the support frame, and is used to mount a lens module; the elastic assemblies are fixed to opposite sides of the support frame in the optical axis direction, and elastically suspend the lens barrel holder within the accommodation space; the image stabilization coil is fixed to the base, the magnetic steel is fixed to the support frame and faces the image stabilization coil with a gap therebetween, and the image stabilization coil cooperates with the magnetic steel to drive the lens barrel holder to move synchronously, thereby moving the support frame in a direction perpendicular to an optical axis of the lens barrel holder; the image stabilization coil is ring-shaped, and a side of the image stabilization coil that is close to the central hole is provided with an arc-shaped structure that is curved and concave in a direction away from the central hole, and the arc-shaped structure matches the outer circumferential shape of the central hole so that the image stabilization coil is positioned completely outside the range of the central hole; the lens driving device further includes a flexible substrate for connection to an external power source, the flexible substrate being fixed to a side of the base close to the magnet steel so as to be in contact with the base, and the plurality of image stabilization coils being laminated and fixed to the flexible substrate and electrically connected to the flexible substrate, The base has a plurality of pairs of protrusions on a side closer to the magnet steel, a plurality of through holes are formed in the flexible substrate, each through hole being capable of receiving one of the plurality of pairs of protrusions; one of the protrusions of each pair passes through the through-hole and is positioned at one end of the image stabilization coil on the inside thereof, the other protrusion of each pair does not penetrate the flexible substrate and is located at the other end inside the image stabilization coil; A lens driving device characterized by:

2. the image stabilization coil has a track shape and includes two long sides that are opposite to each other and two short sides that are opposite to each other, and the arc-shaped structure is provided on the long sides that are close to the center hole; 2. The lens driving device according to claim 1.

3. the base has a rectangular structure; the four image stabilization coils are provided so as to surround the central hole and are fixed to four sides of the base, respectively, and the four image stabilization coils are parallel to the four sides of the base; the four magnetic steel pieces are provided so as to be fixed to the support frame, respectively, and the four image stabilization coils are provided in one-to-one correspondence with the four magnetic steel pieces; 2. The lens driving device according to claim 1.

4. the elastic assembly comprises an upper elastic sheet and a lower elastic sheet, the upper elastic sheet comprises a first fixed arm fixed to the support frame, a second fixed arm fixed to the lens barrel holder, and a plurality of first elastic arms connecting the first fixed arm and the second fixed arm, the first elastic arm being installed at a distance from the support frame along the optical axis direction of the lens barrel holder, the lower elastic sheet comprises a third fixed arm fixed to a side of the support frame closer to the base, a fourth fixed arm fixed to the lens barrel holder, and a second elastic arm connecting the third fixed arm and the fourth fixed arm, the second elastic arm being installed at a distance from the support frame along the optical axis direction of the lens barrel holder.

2. The lens driving device according to claim 1.

5. the lens driving device further includes a plurality of suspension wires, the suspension wires being spaced apart, and both ends of each suspension wire being fixed to the base and the support frame, respectively, so as to suspend the support frame from the base; 5. The lens driving device according to claim 4.

6. The lens driving device further includes a horizontal support elastic member, the horizontal support elastic member including a first arm fixed to the suspension wire, a second arm fixed to the support frame, and an elastic arm connecting the first arm and the second arm.

6. The lens driving device according to claim 5.

7. The support frame includes a rectangular frame body and four fixing structures located at four corners of the support frame, the two upper elastic sheets are provided opposite each other with a gap between them, each upper elastic sheet includes two first elastic arms spaced apart from each other, the four first fixing arms correspond one-to-one to the four fixing structures, and the magnetic steel is fixed to the frame body on the side closer to the lens barrel holder.

7. The lens driving device according to claim 6.

8. the lens driving device further includes a focus coil, the focus coil being fixedly fitted to the lens barrel holder and spaced apart from the magnetic steel, and the focus coil and the magnetic steel working together to drive the lens barrel holder to move along the optical axis direction, thereby realizing an autofocus function.

2. The lens driving device according to claim 1.

9. The flexible substrate further includes a substrate body fixed to the base, and a pin that bends and extends from one side of the substrate body to the base.

2. The lens driving device according to claim 1.

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