Lens drive device

Abstract

The present invention discloses a lens driving device, including a housing, a base, a carrier, a lens driving mechanism and a carrier positioning mechanism. The housing cooperates with the base to form a chamber, the carrier, the lens driving mechanism and the carrier positioning mechanism are arranged in the chamber, the lens driving mechanism includes a driving coil arranged on the base and a magnet group matched with the driving coil, the carrier positioning mechanism includes an iron core, a positioning coil, a spring and a frame, the frame is arranged in the housing and fixedly connected to the base, the spring is fixedly connected to the frame and applies elastic force to the carrier to position the carrier, the iron core is arranged on the frame and is provided with a positioning coil, and when the positioning coil is energized, a force is applied to the spring to separate the spring from the carrier, so that the carrier can move along the optical axis relative to the base. The present invention arranges the driving coil on the base and the magnet group on the carrier, and has the beneficial technical effects of stable power supply performance and long service life.

Description

Technical Field

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

[0002] With the development of technology, many electronic devices (such as smart phones or digital cameras) now have the function of taking photos or recording videos. The use of these electronic devices is becoming more and more common, and they are developing in the direction of convenient and lightweight design to provide users with more choices. However, the lens drive mechanism of current mobile phones and other handheld devices usually sets the coil on the carrier, and sets the magnet group that matches the coil on the base or the shell. During the movement of the carrier, the coil moves with the carrier, which easily causes circuit instability and shortens the service life.

[0003] In addition, current mobile phones and other devices are used in a wide range of scenarios. When used in some places with not-so-good environments, impurities such as dust layers can easily enter the camera device and affect the imaging effect. Summary of the invention

[0004] The object of the present invention is to provide a lens driving device to solve the above problems in the prior art.

[0005] In order to solve the above problem, according to one aspect of the present invention, a lens driving device is provided, characterized in that the lens driving device comprises a housing, a base, a carrier, a lens driving mechanism and a carrier positioning mechanism, the housing and the base cooperate to form a chamber, the carrier, the lens driving mechanism and the carrier positioning mechanism are arranged in the chamber,

[0006] The lens driving mechanism is used to drive the carrier to move relative to the base and includes a driving coil disposed on the base and a magnet group matched with the driving coil.

[0007] The carrier positioning mechanism includes an iron core, a positioning coil, a spring and a frame, wherein the frame is arranged in the shell and fixedly connected to the base, the spring is fixedly connected to the frame and applies elastic force to the carrier to position the carrier, the iron core is arranged on the frame and is provided with the positioning coil, and when the positioning coil is energized, a force is applied to the spring to separate the spring from the carrier, so that the carrier can move along the optical axis relative to the base.

[0008] In one embodiment, the carrier positioning mechanism also includes a positioning piece, one end of the spring sheet is fixedly connected to the frame, and the other end of the spring sheet is provided with the positioning piece, the positioning piece cooperates with the carrier and fixes the carrier under the elastic force of the spring sheet, and detaches from the carrier when the positioning coil is energized.

[0009] In one embodiment, the lens driving device also includes a carrying sleeve and a movable sleeve, the base is provided with a cylindrical protrusion, the carrying sleeve is arranged on the inner side of the cylindrical protrusion and is used to connect the lens, the movable sleeve is arranged on the outer side of the cylindrical protrusion, and the magnet group is arranged between the cylindrical protrusion and the movable sleeve and arranged around the cylindrical protrusion.

[0010] In one embodiment, the top of the bearing sleeve is provided with an edge protrusion and is fixedly connected to the top of the magnet, the top of the movable sleeve is connected to the top of the bearing sleeve, and the bottom of the movable sleeve and the bottom of the magnet group are fixedly connected to the carrier.

[0011] In one embodiment, the base is provided with a built-in circuit board, the coil is electrically connected to the built-in circuit board of the base through a terminal, and the magnet group includes a plurality of magnets, and avoidance gaps are provided between the plurality of magnets to avoid the terminal.

[0012] In one embodiment, the base includes a bottom and a cylindrical protrusion, the cylindrical protrusion is formed by extending upward from the bottom as a whole, the outer side wall of the cylindrical protrusion is provided with a coil groove, and the driving coil is arranged in the coil groove.

[0013] In one embodiment, the lens driving device further includes a guide column, which is fixedly mounted on the bottom of the base, and the carrier is provided with a guide hole, and the guide column cooperates with the guide hole to guide the carrier.

[0014] In one embodiment, the lens driving device also includes a flexible circuit board and a magnetic grid, one end of the flexible circuit board is fixedly connected to the carrier and is provided with a position sensor, the other end of the flexible circuit board is electrically connected to the built-in circuit board of the base, and the magnetic grid is arranged on the frame or the housing and cooperates with the position sensor.

[0015] In one embodiment, the lens driving device also includes a filter and an FPC module, wherein the FPC module is disposed below the base and electrically connected to a circuit board built into the base, and the filter is disposed in a bottom groove of the base and cooperates with the lens.

[0016] In one embodiment, the lens driving device further comprises a lens and a glass cover, wherein the glass cover is disposed at the front end of the lens and arranged inside the top end of the movable sleeve and connected to the top end of the edge protrusion of the movable sleeve.

[0017] In one embodiment, the built-in circuit board of the base has eight output pins, two of which are used to be electrically connected to the drive coil, two are used to be electrically connected to the positioning coil, four are used to be electrically connected to the flexible circuit board, and the input end of the built-in circuit board of the base is electrically connected to the FPC module, thereby realizing power supply operation for the drive coil, the positioning coil and the flexible circuit board.

[0018] The present invention creatively arranges the driving coil on the base, arranges the magnet group matched with the driving coil on the carrier, and realizes power supply to the driving coil through a unique structural design, which has the beneficial technical effects of stable power supply performance and long service life. In addition, in some embodiments, the present invention also realizes excellent dustproof effect through a unique dustproof structural design. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A perspective exploded view of a lens driving device according to an embodiment of the present invention is shown.

[0020] Figure 2 and Figure 3 It is a stereoscopic diagram of different viewing angles of some components of a lens device according to an embodiment of the present invention after being assembled.

[0021] Figure 4 FIG. 1 is a perspective view of a frame of a lens driving device according to an embodiment of the present invention.

[0022] Figure 5 is a cross-sectional view of a lens driving device according to an embodiment of the present invention.

[0023] Figure 6 The figure is a three-dimensional diagram of a base of a lens driving device according to an embodiment of the present invention.

[0024] Figure 7 It is a circuit connection diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings so that the purpose, features and advantages of the present invention can be more clearly understood. It should be understood that the embodiments shown in the accompanying drawings are not intended to limit the scope of the present invention, but are only intended to illustrate the essential spirit of the technical solution of the present invention.

[0026] In the following description, certain specific details are set forth for the purpose of illustrating the various disclosed embodiments to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the relevant art will recognize that the embodiments may be practiced without one or more of these specific details. In other cases, well-known devices, structures, and techniques associated with the present application may not be shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0027] References throughout the specification to "one embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any manner in one or more embodiments.

[0028] In the following description, in order to clearly show the structure and working mode of the present invention, many directional words will be used for description, but the words "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", "down", etc. should be understood as convenient terms and should not be understood as restrictive terms.

[0029] The present application generally relates to a lens driving device, which can be used in terminal products such as mobile phones and tablet computers to cooperate with lenses to realize functions such as taking pictures and recording videos. For the convenience of description, the present application introduces the concept of "optical axis" to indicate the propagation direction of light in an optical element. It is an abstract concept and does not refer to the existence of an axis in a physical sense. The direction along the optical axis is called the longitudinal direction.

[0030] Figure 1 A perspective exploded view of a lens driving device according to an embodiment of the present invention is shown. Figure 2 and Figure 3 1 is a stereoscopic diagram of different viewing angles of the assembled partial components of a lens device according to an embodiment of the present invention, such as Figure 1-3As shown, the lens driving device 100 includes a housing 10, a base 20, a carrier 30, a lens driving mechanism 40 and a carrier positioning mechanism 50. The housing 10 cooperates with the base 20 to form a chamber. The carrier 30, the lens driving mechanism 40 and the carrier positioning mechanism 50 are arranged in the chamber. The lens driving mechanism 40 includes a driving coil 41 arranged on the base 20 and a magnet group 42 matched with the driving coil 41 and is used to drive the carrier 30 to move relative to the base 20 to achieve an optical zoom function. The carrier positioning mechanism 50 includes a spring 51, an iron core 52, a positioning coil 53 and a frame 54. The frame 54 4 is arranged in the housing 10 and fixedly connected to the base 20, the spring sheet 51 is fixedly connected to the frame 54 and applies elastic force to the carrier 30 to position the carrier 30, the iron core 52 is arranged on the frame 54 and is provided with a positioning coil 53, the carrier positioning mechanism 50 is equivalent to a control switch for positioning the carrier 30, when the positioning coil 53 is not energized, the spring sheet 51 applies elastic force to the carrier, and the carrier 30 cannot move relative to the base 20, and when the positioning coil 53 is energized, the iron core 52 applies force to the spring sheet 51 to overcome the elastic force of the spring sheet 51, so that the carrier 30 can move relative to the base 20. For example, when optical zoom is required, the positioning coil 53 is energized, the iron core 52 applies force to the spring sheet 51 to overcome the elastic force of the spring sheet 51, and the lens driving mechanism drives the carrier 30 to move longitudinally to achieve the zoom function. When optical zoom is not required, the positioning coil 53 is de-energized, the spring sheet 51 applies force to the carrier 30, and the carrier 30 is relatively fixed to the base 20, thereby ensuring the stability of the carrier 30 and preventing the carrier 30 from moving longitudinally relative to the base together with the lens under the action of gravity when a mobile phone, tablet computer or other device equipped with the lens driving device of the present invention is inverted.

[0031] Continue to refer to Figure 1-3 In one embodiment, the carrier positioning mechanism also includes a positioning member 55. One end of the spring sheet 51 is fixedly connected to the frame 54. The other end of the spring sheet 51 is provided with the positioning member 55. The positioning member 55 cooperates with the carrier 30 and fixes the carrier 30 under the elastic force of the spring sheet 51, and is detached from the carrier 30 when the positioning coil 53 is energized.

[0032] Specifically, refer to Figure 4, which shows a three-dimensional view of a frame 54 of an embodiment of the present invention. The top of the frame 54 is provided with an opening 541 for matching with the lens and the bottom is open to match with the carrier. The side wall of the frame 54 is provided with a spring installation groove 542 and a positioning member installation groove 543 to respectively install the spring 51 and the positioning member 55. The positioning member 55 is engaged with the top of the carrier 30 under the elastic force of the spring 51, so that the carrier 30 cannot move longitudinally, ensuring the stability of the carrier 30. When the positioning coil 53 is energized, the iron core 52 attracts the positioning member 55, and the positioning member 55 moves away from the carrier 30 and detaches from the carrier 30, and no longer engages with the carrier 30, so that the carrier 30 and the lens can move longitudinally by energizing the driving coil 41 to realize the optical zoom function. When the carrier 30 and the lens are reset, the positioning coil 53 is powered off, and the positioning member 55 positions the carrier 30 again under the elastic action of the spring 51.

[0033] Figure 5 FIG. 2 is a cross-sectional view of a lens driving device according to an embodiment of the present invention. Figure 1 and Figure 5 As shown, in one embodiment of the present invention, the lens driving device 100 also includes a carrying sleeve 60 and a movable sleeve 70, the base 20 is provided with a cylindrical protrusion 21, the outer peripheral wall of the cylindrical protrusion 21 is provided with a coil groove 211, the driving coil 41 is arranged in the coil groove 211, the carrying sleeve 60 is arranged on the inner side of the cylindrical protrusion 21 and is used to connect the lens, the movable sleeve 70 is arranged on the outer side of the cylindrical protrusion 21, and the magnet group 42 is arranged between the cylindrical protrusion 21 and the movable sleeve 70 and arranged around the cylindrical protrusion 21.

[0034] Optionally, the top of the supporting sleeve 60 is provided with an edge protrusion 61 and is fixedly connected to the top of the magnet group 42, the top of the movable sleeve 70 is fixedly connected to the top of the supporting sleeve 60, and the bottom end of the movable sleeve 70 and the bottom end of the magnet group 42 are fixedly connected to the carrier 30.

[0035] A complex dustproof structure can be formed by the cylindrical protrusion 21 of the base 20, the bearing sleeve 60 and the movable sleeve 70, such as Figure 2As shown, when dust and other impurities enter from the top, due to the shielding of the movable sleeve 70 and the top of the bearing sleeve 60, they can only move toward the base along the gap between the inner wall of the frame 54 and the outer wall of the movable sleeve 70, and when approaching the top of the carrier 30, they move downward along the outer wall of the carrier 30, and then can only enter from the bottom of the carrier and be blocked by the cylindrical protrusion 21, and then can only move upward along the gap between the inner wall of the magnet group 42 and the outer wall of the cylindrical protrusion 21, and when reaching the top, they are blocked by the edge protrusion 61 of the bearing sleeve 60, and then move downward along the outer wall of the bearing sleeve 60. Therefore, dust and other impurities need to go through at least two 180-degree path bends to enter the interior, so that the dustproof structure achieves excellent dustproof effect through complex path design.

[0036] In addition, in one embodiment of the present invention, the drive coil is arranged on the base, and the magnet group is fixedly arranged in the frame and fixedly connected to the carrier by means of the frame, that is, the magnet group is indirectly fixed to the carrier. This is obviously different from the conventional design of arranging the drive coil on the carrier and arranging the magnet in the base or the shell. Since the drive coil is arranged on the base and can be connected to the external circuit through the built-in circuit board of the base, the drive coil does not need to move with the carrier during the movement of the carrier, and has a longer service life, durability and stability.

[0037] In one embodiment, Figure 1 As shown, the base 20 is provided with a built-in circuit board, the driving coil 41 is electrically connected to the built-in circuit board of the base through the terminal 411, and the magnet group 42 includes a plurality of magnets, and avoidance gaps are provided between the plurality of magnets to avoid the terminal 411.

[0038] Figure 6 FIG. 2 is a perspective view of a base 20 according to an embodiment of the present invention. In one embodiment, the base 20 is connected to the carrier 30 via a guide column 25. Figure 6 As shown, the base 20 includes a bottom 22 and a cylindrical protrusion 21 extending upward from the bottom 22. A coil groove 23 is provided in the area near the top of the outer wall of the cylindrical protrusion 21, and the driving coil 41 is arranged in the coil groove 23. The bottom 22 is also provided with a guide post mounting hole 24, which is used to fix and install the guide post 25. Correspondingly, the carrier 30 is provided with a guide hole that cooperates with the guide post 25. The base 20 and the carrier 30 are connected by the guide fixing hole and the guide post 25, and the carrier 30 can move relative to the base along the guide post, thereby guiding the movement of the carrier 30.

[0039] Return to reference Figure 2-3In one embodiment, the lens driving device 100 further includes a flexible circuit board 81 and a magnetic grid 82. One end of the flexible circuit board 81 is fixedly connected to the carrier 30 and is provided with a position sensor 811. The other end of the flexible circuit board 81 is electrically connected to the embedded metal sheet of the base 20, thereby connecting to an external circuit. The magnetic grid 82 is arranged on the frame 54 or the housing 10 and cooperates with the position sensor 811. When the position sensor 811 follows the carrier 30 to perform longitudinal movement, the position of the carrier 30 can be monitored through the magnetic grid 82.

[0040] Optionally, return a reference Figure 4 A side wall of the frame 54 is provided with an FPC board (flexible circuit board) avoidance groove 544 and a magnetic grid installation groove 545. The FPC board avoidance groove 544 is used for the avoidance operation when the flexible circuit board 81 and the position sensor 811 move longitudinally, and the magnetic grid installation groove 545 is used to install the magnetic grid 82. It should be understood by those skilled in the art that in other embodiments, the magnetic grid 82 can also be installed on the inner wall of the housing 10, and the magnet magnetic grid installation groove 545 is used as an avoidance groove. The purpose can be achieved as long as the position sensor 811 corresponds to the magnetic grid 82.

[0041] In one embodiment, referring to Figure 6 A terminal groove 26 is also provided on the outer side wall of the cylindrical protrusion 21 of the base 20 for installing a terminal 411 connecting the driving coil 41 and the flexible circuit board 81.

[0042] In one embodiment, referring to Figure 1 and Figure 6 The lens driving device 100 also includes a filter 83 and an FPC module 84. The FPC module 84 is arranged at the bottom of the base 20 and is electrically connected to the built-in circuit board of the base. The filter 83 is arranged in the bottom groove of the base and is arranged opposite to the lens.

[0043] Figure 7 FIG. 1 is a schematic diagram of line connection of an embodiment of the present invention. Figure 7 As shown, the built-in circuit board 27 of the base has eight output pins 271, two of which are used to be electrically connected to the terminal 411 of the drive coil 41, the other two are used to be electrically connected to the positioning coil 53, and the remaining four are used to be connected to one end of the flexible circuit board 81. The input end of the built-in circuit board of the base is electrically connected to the FPC module 84, thereby realizing the power supply operation of the drive coil 41, the positioning coil 53 and the flexible circuit board 81.

[0044] The preferred embodiments of the present invention have been described in detail above, but it should be understood that after reading the above teachings of the present invention, those skilled in the art may 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 comprises a housing, a base, a carrier, a lens driving mechanism and a carrier positioning mechanism. The housing and the base cooperate to form a chamber. The carrier, the lens driving mechanism and the carrier positioning mechanism are arranged in the chamber. The lens driving mechanism is used to drive the carrier to move relative to the base and includes a driving coil arranged on the base and a magnet group matched with the driving coil, wherein the magnet group is arranged on the carrier; The carrier positioning mechanism includes an iron core, a positioning coil, a spring and a frame, wherein the frame is arranged in the shell and fixedly connected to the base, the spring is fixedly connected to the frame and applies elastic force to the carrier to position the carrier, the iron core is arranged on the frame and is provided with the positioning coil, and when the positioning coil is energized, a force is applied to the spring to separate the spring from the carrier, so that the carrier can move along the optical axis relative to the base.

2. The lens driving device according to claim 1, characterized in that: The carrier positioning mechanism also includes a positioning piece, one end of the spring sheet is fixedly connected to the frame, the other end of the spring sheet is provided with the positioning piece, the positioning piece cooperates with the carrier and fixes the carrier under the elastic force of the spring sheet, and detaches from the carrier when the positioning coil is energized.

3. The lens driving device according to claim 1, characterized in that: The lens driving device also includes a carrying sleeve and a movable sleeve. The base is provided with a cylindrical protrusion. The carrying sleeve is arranged on the inner side of the cylindrical protrusion and is used to connect the lens. The movable sleeve is arranged on the outer side of the cylindrical protrusion. The magnet group is arranged between the cylindrical protrusion and the movable sleeve and is arranged around the cylindrical protrusion.

4. The lens driving device according to claim 3, characterized in that: The top of the bearing sleeve is provided with an edge protrusion and is fixedly connected to the top of the magnet, the top of the movable sleeve is connected to the top of the bearing sleeve, and the bottom of the movable sleeve and the bottom of the magnet group are fixedly connected to the carrier.

5. The lens driving device according to claim 1, characterized in that: The base is provided with a built-in circuit board, the coil is electrically connected to the built-in circuit board of the base through a terminal, and the magnet group includes a plurality of magnets, and avoidance gaps are provided between the plurality of magnets to avoid the terminal.

6. The lens driving device according to claim 1, characterized in that: The base includes a bottom and a cylindrical protrusion, wherein the cylindrical protrusion is formed by extending upward from the bottom as a whole, and an outer wall of the cylindrical protrusion is provided with a coil groove, and the driving coil is arranged in the coil groove.

7. The lens driving device according to claim 6, characterized in that: The lens driving device further comprises a guide column, which is fixedly mounted on the bottom of the base. The carrier is provided with a guide hole, and the guide column cooperates with the guide hole to guide the carrier.

8. The lens driving device according to claim 5, characterized in that: The lens driving device also includes a flexible circuit board and a magnetic grid. One end of the flexible circuit board is fixedly connected to the carrier and is provided with a position sensor. The other end of the flexible circuit board is electrically connected to the built-in circuit board of the base. The magnetic grid is arranged on the frame or the housing and cooperates with the position sensor.

9. The lens driving device according to claim 8, characterized in that: The lens driving device also includes a filter and an FPC module. The FPC module is arranged below the base and electrically connected to the built-in circuit board of the base. The filter is arranged in the bottom groove of the base and cooperates with the lens.

10. The lens driving device according to claim 4, characterized in that: The lens driving device further comprises a lens and a glass cover. The glass cover is arranged at the front end of the lens and disposed inside the top end of the movable sleeve and connected to the top end of the edge protrusion of the movable sleeve.

11. The lens driving device according to claim 9, characterized in that: The built-in circuit board of the base has eight output pins, two of which are used to be electrically connected to the drive coil, two are used to be electrically connected to the positioning coil, four are used to be electrically connected to the flexible circuit board, and the input end of the built-in circuit board of the base is electrically connected to the FPC module, thereby realizing the power supply operation of the drive coil, the positioning coil and the flexible circuit board.

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