JP6297433B2 - Lens drive device - Google Patents

Description

  The present invention relates to a lens driving device.

  2. Description of the Related Art A lens driving device including an electromagnetic driving type driving unit including a coil and a magnet is known. Such a lens driving device includes an autofocus driving device that drives the lens frame along the optical axis direction, and a camera shake correction driving device that drives the lens frame in a direction intersecting the optical axis.

  The prior art described in the following Patent Document 1 moves the entire autofocus lens driving device in a first direction (X direction) and a second direction (Y direction) that are orthogonal to the optical axis and orthogonal to each other. Is a camera shake correction device configured to perform camera shake correction, and a base that is spaced apart from the bottom surface portion of the autofocus lens driving device and one end fixed at the outer peripheral portion of the base, and the optical axis And a plurality of suspension wires that support the entire autofocus lens driving device so as to be swingable in a first direction (X direction) and a second direction (Y direction).

  In this prior art, the lens frame around which the focus coil is wound is supported by a magnet holder that is arranged around the lens frame via a leaf spring for autofocus, and supports the front end of the lens frame. The front end of the suspension wire is fixed to the outer periphery of the leaf spring. Accordingly, in the autofocus lens driving device, the magnet holder that elastically supports the lens frame via the leaf spring is supported in a suspended state at the front ends of the plurality of suspension wires extending in the optical axis direction.

JP 2011-65140 A

  In the conventional lens driving device described above, when an external force along the optical axis acts on the lens driving device for autofocus, a buckling load is applied to the suspension wire that supports the lens suspension device in a suspended state, and an excessive external force is applied. If added, the suspension wire may be damaged. In order to cope with this, an arm portion that elastically absorbs a compressive force applied to the suspension wire is provided on a leaf spring to which the tip of the suspension wire is fixed.

  However, when such an arm portion is provided, the leaf spring is likely to vibrate due to the swing of the suspension wire accompanying the camera shake correction, and there arises a problem that the movement of the lens frame becomes unstable due to resonance and oscillation caused by the leaf spring. In particular, due to the demand for smaller and lighter lens drive devices, the drive unit has been reduced in size and the thrust has been reduced. In order to cope with this, it is necessary to weaken the force of the leaf spring. There is a need to suppress resonance and oscillation caused by a leaf spring without affecting the force.

  This invention makes it an example of a subject to cope with such a problem. That is, an object of the present invention is to stabilize the movement of the lens frame by suppressing resonance and oscillation caused by the leaf spring without affecting the force of the leaf spring.

In order to achieve such an object, a lens driving device according to the present invention has the following configuration.
A lens frame, a movable support member that surrounds the lens frame around the optical axis, a leaf spring that elastically supports the lens frame on the movable support member for driving in the optical axis direction, and a rear side of the movable support member A base support member, a support wire that is erected from the base support member along the optical axis and that crosses the optical axis, and elastically supports the movable support member, and the lens frame in the optical axis direction. And a drive unit that drives in one or both of the directions intersecting the optical axis, and the leaf spring is fixed to a front end of the movable support member and a corner fixed to the front end of the support wire A pair of arm portions that elastically connect the fixing portion and the corner portion, and a connection portion that connects the pair of arm portions, and the arm portion is connected to the one end from the both ends of the fixing portion. It extends toward the corner, and the connecting portion is a pair of the arm portions The hung in an arch shape, and the corner portion has an opening formed between the connecting portion, the front end of the movable support member, the connecting portion and the stepped portion providing a gap between the arm portion A lens driving device comprising: an adhesive member reservoir that is recessed along the adhesive member, wherein the adhesive member stored in the adhesive member reservoir is in contact with the connecting portion.

It is a disassembled perspective view of the lens drive device concerning the embodiment of the present invention. It is explanatory drawing ((a) is a top view, (b) is XX sectional drawing of (a)) which showed the whole structure which concerns on embodiment of this invention. An explanatory view showing a movable support member and a leaf spring in a lens drive device concerning an embodiment of the present invention ((a) is a plane showing a state where front blade springs 11 and 12 are attached to lens frame 2 and movable support member 10 (B) is a plan view of the lens frame 2 and the movable support member 10 with the front leaf springs 11 and 12 removed. FIG. 4A is an explanatory diagram showing in detail the main part of FIG. 3 (FIG. 4A is a plan view, and FIG. 4B is a sectional view taken along line XX in FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing ((a) is a camera, (b) is a portable information terminal) which showed the electronic device provided with the lens drive device which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an exploded perspective view of a lens driving device according to an embodiment of the present invention, and FIG. 2 shows an overall configuration according to the embodiment of the present invention ((a) is a plan view, (b) ) Is an XX sectional view of (a).

  The lens driving device 1 includes a lens frame 2, a support unit 3, and a driving unit 4. The lens frame 2 includes a lens barrel attachment port 2S for attaching a lens barrel (not shown). The central axis of the lens barrel mounting port 2S is the optical axis of the lens. Hereinafter, the object side of the lens will be described as “front”, and the image side of the lens will be described as “rear”. In the figure, the optical axis direction is indicated by the Z direction, and the directions intersecting the optical axis are indicated by the X and Y directions.

  The drive unit 4 drives the lens frame 2 in one or both of the optical axis direction and the direction intersecting the optical axis. In the illustrated example, the drive unit 4 includes a focus coil 20 wound around the body of the lens frame 2 around the optical axis, four magnets 21 arranged around the lens frame 2, and four magnets 21. A camera shake correction coil 22 (22A, 22B) is provided behind each of the two magnetic field directions orthogonal to each other.

  The support unit 3 elastically supports the lens frame 2 in the driving direction of the driving unit 4. The position of the lens frame 2 is controlled by a balance between the thrust of the drive unit 4 and the elastic force of the support unit 3. In the illustrated example, the support unit 3 includes a movable support member 10, front plate springs (plate springs) 11 and 12, a rear plate spring (plate spring) 13, a support wire 14, and a base support member 15. The movable support member 10 surrounds the lens frame 2 around the optical axis, elastically supports the lens frame 2 in the optical axis direction, and is elastically supported in a direction intersecting the optical axis. The illustrated movable support member 10 has a rectangular shape having a corner around the optical axis, and the corner serves as a magnet holding portion 10P that holds the magnet 21 described above.

  Front end attachment portions 10A and 10B of the movable support member 10 are attached with outer attachment portions 11A and 11B of the front leaf spring 11, and an inner attachment portion 11C of the front leaf spring 11 is provided on the front surface 2A of the lens frame 2. It is attached to the part 2A1. Front end attachment portions 10C, 10D of the movable support member 10 are attached with outer attachment portions 12B, 12A of the front leaf spring 12, and an inner attachment portion 12C of the front leaf spring 12 is provided on the front surface 2A of the lens frame 2. It is attached to the part 2A2.

  The front leaf spring 11 includes elastic portions 11D and 11E between the outer attachment portions 11A and 11B and the inner attachment portion 11C. Similarly, the front leaf spring 12 includes the outer attachment portions 12A and 12B and the inner attachment portion. The elastic parts 12E and 12D are provided between 12C.

  An outer attachment portion 13A of the rear leaf spring 13 is attached to the rear end attachment portion 10E of the movable support member 10, and an inner attachment portion 13B of the rear leaf spring 13 is attached to the rear attachment portion 2C provided on the rear surface of the lens frame 2. It is attached. The rear leaf spring 13 includes an elastic portion 13C between the outer attachment portion 13A and the inner attachment portion 13B.

  The front side of the lens frame 2 is supported on the front side of the movable support member 10 via the front leaf springs 11 and 12 including the elastic portions 11D, 11E, 12D, and 12E, and the rear side of the lens frame 2 includes the elastic portion 13C. It is supported on the rear side of the movable support member 10 via the rear leaf spring 13. Thus, the lens frame 2 is elastically supported by the movable support member 10 for driving in the optical axis direction.

  The base support member 15 is disposed behind the lens frame 2 and the movable support member 10, and includes a central opening 15A through which light passing through the lens passes through the bottom plate 15B. In the illustrated example, the base support member 15 has a rectangular shape with corners around the optical axis, like the movable support member 10, and includes wire holding portions 15C at the corners.

  The support wire 14 (14A, 14B, 14C, 14D) has elasticity with respect to the curvature, and the rear end is held by the wire holding portion 15C of the base support member 15 and is erected along the optical axis. Yes. The front ends of the support wires 14A, 14B, 14C, 14D are attached to the outer attachment portions 11A, 12A, 11B, 12B of the front leaf springs 11, 12 attached to the movable support member 10, and the support wire 14 Supports the movable support member 10 that elastically supports the lens frame 2 in a suspended manner. As a result, the base support member 15 elastically supports the movable support member 10 with respect to driving in the direction intersecting the optical axis, and the lens frame 2 intersects the optical axis due to the elastic curve of the support wire 14. It is elastically supported with respect to the driving in the direction.

  The base support member 15 includes an external connection terminal 15 </ b> F, and includes a circuit connected to the external connection terminal 15 </ b> F on the bottom plate 15 </ b> B, thereby configuring a power feeding end to the drive unit 4. Part of the external connection terminal 15F having a plurality of independent terminals is provided at both ends of the camera shake correction coil 22 (22A, 22B) supported by the coil support portion 15D of the base support member 15 via a circuit provided in the bottom plate 15B. It is connected and serves as a power supply terminal of the camera shake correction coil 22.

  A part of the external connection terminal 15F is connected to both ends of the focus coil 20 from the circuit provided in the bottom plate 15B via the support wires 14A and 14B held by the wire holding portion 15C and the front leaf springs 11 and 12. The focus coil 20 is a power supply terminal.

  Further, a part of the external connection terminal 15F is connected to the position detection sensor 6 (6A, 6B) supported by the sensor support portion 15E of the base support member 15 via a circuit provided in the bottom portion 15B. It is an input / output terminal of the sensor 6 (6A, 6B).

  By controlling power feeding to the focus coil 20 and the camera shake correction coil 22 independently, focus control and camera shake correction control of the lens frame 2 can be performed. At that time, the camera shake correction control is feedback control based on the detection signal of the position detection sensor 6 (6A, 6B). A filter frame F is mounted behind the base support member 15, and an imaging element (not shown) is mounted behind the filter frame F. A protective frame 5 having a central opening 5 </ b> A is attached to the base support member 15 so as to surround the outer periphery of the movable support member 10.

  3 and 4 show the movable support member 10 and the leaf springs (front leaf springs 11 and 12) arranged around the lens frame 2. 3A is a plan view showing a state in which the front leaf springs 11 and 12 are attached to the lens frame 2 and the movable support member 10, and FIG. 3B is a state in which the front leaf springs 11 and 12 are removed. 2 is a plan view of a lens frame 2 and a movable support member 10. FIG. 4A and 4B are explanatory views showing in detail the main part of FIG. 3 (FIG. 4A is a plan view, and FIG. 4B is an XX cross-sectional view in FIG. 4A).

  The outer attachment portions 11A, 11B, 12A, and 12B of the front leaf springs 11 and 12 include a corner portion 40 that is fixed to the front end of the support wire 14, a fixing portion 41 that is fixed to the front end of the movable support member 10, and a fixing portion. A pair of arm portions 42 that elastically connect 41 and the corner portion 40 and a connection portion 43 that connects between the pair of arm portions 42 are provided. The corner portion 40 is disposed at a position corresponding to the corner portion 10H of the movable support member 10, and is positioned at the apex of the substantially triangular outer mounting portions 11A, 11B, 12A, and 12B. The fixed portion 41 is located at the center of the substantially triangular outer mounting portions 11A, 11B, 12A, and 12B, and is fixed to the mounting surface 10J of the front end mounting portions 10A, 10B, 10C, and 10D of the movable support member 10. ing.

  The pair of arm portions 42 are located on the outer peripheral portions of the substantially triangular outer mounting portions 11A, 11B, 12A, and 12B, and the corner portions 40 are located with respect to the fixed portion 41 that is fixed to the front end of the movable support member 10. The fixed portion 41 and the corner portion 40 are elastically connected so that the position can be displaced up and down. The connecting portion 43 connects the pair of arm portions 42 in an arch shape, and an opening is formed between the connecting portion 43 and the corner portion 40.

  On the other hand, the front end attaching portions 10A, 10B, 10C, and 10D of the movable support member 10 to which the outer attaching portions 11A, 11B, 12A, and 12B of the front leaf springs 11 and 12 are attached have a concave corner portion 10H in a plan view. The inside is a space for arranging the support wire 14, and the corner portions 40 of the front leaf springs 11 and 12 are arranged thereon and fixed to the tip of the support wire 14. A pair of anti-rotation convex portions 10G is provided for each corner portion 10H so as to protrude outside the pair of arm portions 42 of the front side leaf springs 11 and 12 at a position close to the corner portion 10H. The arm portions 42 of the front leaf springs 11 and 12 are protected.

  The front end attaching portions 10A, 10B, 10C, and 10D of the movable support member 10 are stepped portions that are positioned below the pair of arm portions 42 in the front leaf springs 11 and 12 and have a gap with the arm portions 42. 10K and an adhesive member reservoir 10L which is located below the connecting portion 43 in the front leaf springs 11 and 12 and is recessed along the connecting portion 43 are provided.

  The step portion 10K in the movable support member 10 is formed one step down from the mounting surface 10J to which the fixing portion 41 of the front plate springs 11 and 12 is fixed, and only allows the bending of the arm portion 42 in the front plate springs 11 and 12. It has a dent. Further, the adhesive member reservoir 10L has a recess which is lower than the recess of the stepped portion 10K and is deeper than the recess 10D. The outer surface of the adhesive member reservoir 10L is flush with the attachment surface 10J. A wall portion 10N having a thickness is provided. The wall portion 10N is located in the opening between the corner portion 40 and the connecting portion 43 of the front leaf springs 11 and 12. An adhesive member for damping vibration is stored in the adhesive member reservoir 10L, and the adhesive member is stored in contact with the connecting portion 43 of the front leaf springs 11 and 12 located on the adhesive member reservoir 10L.

  The adhesive member reservoir 10L has an inner wall at the level difference from the mounting surface 10J and an outer wall at the level difference from the wall 10N. Further, the adhesive member reservoir 10L has left and right walls that are stepped from the stepped portion 10K. Thus, since the adhesive member reservoir 10L is a recess having a wall around it, the vibration damping adhesive member having a relatively high viscosity stored in the reservoir 10L does not flow out to the outside. It is possible to maintain the state of being stored in the pool.

  The lens frame 2 arranged on the inner side of the movable support member 10 is provided with stopper projections 2B and vibration-attenuating projections 30 on its four sides, and the movable support member 10 corresponds to the stopper projections 2B. The stopper receiver 10M is provided, and the concave portion 31 is provided corresponding to the protruding portion 30. The stopper support 10 </ b> M provided on the movable support member 10 is excessive in the direction intersecting the optical axis of the lens frame 2 in the movable support member 10 by hitting the stopper projection 2 </ b> B provided on the lens frame 2. The movement is regulated. Moreover, an adhesive member for damping vibration is accommodated between the concave portion 31 provided in the movable support member 10 and the protruding portion 30 protruding therein, and unnecessary vibration of the lens frame 2 is suppressed by this adhesive member. doing.

  The lens driving device 1 having such a feature elastically connects the corner portion 40 where the front leaf springs 11 and 12 are fixed to the front end of the support wire 14 and the fixing portion 41 fixed to the front end of the movable support member 10. Therefore, even when an external force in the optical axis direction is applied to the movable support member 10, the arm portion 42 can elastically absorb the external force and reduce the load applied to the support wire 14. it can. Further, the front leaf springs 11 and 12 include a connecting portion 43 that connects the pair of arm portions 42, and the movable support member 10 has an adhesive property that collects a vibration-damping adhesive member that contacts the connecting portion 43. Since the member reservoir 10L is provided, vibration transmitted from the support wire 14 to the pair of arm portions 42 via the corner portion 40 can be effectively attenuated. Accordingly, even when the force of the front leaf springs 11 and 12 is weakened, resonance and oscillation caused by the leaf springs can be effectively suppressed, and the movement of the lens frame 2 can be stabilized.

  Further, the adhesive member reservoir 10L provided on the movable support member 10 is provided with a wall around it so that the vibration-damping adhesive member accumulated therein is less likely to flow out. In the case of receiving the vibration, vibrations transmitted to the front leaf springs 11 and 12 can be effectively damped by holding the adhesive member in the adhesive member reservoir 10L.

  Further, the connecting portion 43 that connects the pair of arm portions 42 in an arch shape is deformed in a direction in which the pair of arm portions 42 intersects the optical axis in addition to the function of making contact with the vibration damping adhesive member. Therefore, even when the force of the front leaf springs 11 and 12 is weakened, the lens frame 2 can be effectively prevented from shaking.

  FIG. 5 shows an electronic apparatus including the lens driving device 1 according to the embodiment of the present invention. The lens driving device 1 according to the embodiment of the present invention can be reduced in size and can have high autofocus performance or camera shake correction performance by being mounted on the camera 100 shown in FIG. . Moreover, by mounting on the portable information terminal (including a mobile phone, a smart phone, etc.) 200 shown in FIG. 5B, the entire device can be made thinner, the camera function part can be enhanced, and the space can be saved. .

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and the design can be changed without departing from the scope of the present invention. Is included in the present invention. In addition, the above-described embodiments can be combined by utilizing each other's technology as long as there is no particular contradiction or problem in the purpose and configuration. In addition, the adhesive member in embodiment mentioned above should just be a member which has damping property, such as an ultraviolet curable resin, a thermosetting resin, and grease.

1: lens driving device, 2: lens frame, 2A: front surface,
2B: Stopper protrusion, 2B1, 2B2: Stopper surface,
2A1, 2A2: Front end mounting portion, 2S: Lens barrel mounting port,
2C: Rear mounting part,
3: support part, 4: drive part, 5: protective frame, 5A: central opening,
6 (6A, 6B): position detection sensor,
10: movable support member, 10A, 10B, 10C, 10D: front end mounting portion,
10E: Rear end mounting portion, 10P: Magnet holding portion,
10F: outer peripheral surface, 10G: rotation stopper convex portion, 10H: corner portion,
10J: mounting surface, 10K: stepped portion, 10L: adhesive member reservoir, 10N: wall portion,
10M: Stopper surface,
11, 12: Front leaf spring (leaf spring),
11A, 11B, 12A, 12B: outside attachment part,
11C, 12C: inner mounting part,
11D, 11E, 12D, 12E: elastic part,
13: Rear leaf spring (leaf spring),
13A: outside attachment part, 13B: inside attachment part,
13C: Elastic part, 14 (14A, 14B, 14C, 14D): Support wire,
15: Base support member, 15A: Center opening, 15B: Bottom plate,
15C: wire holding part, 15D: coil support part, 15E: sensor support part,
15F: External connection terminal,
20: Focus coil, 21: Magnet,
22 (22A, 22B): camera shake correction coil,
30: Projection, 31: Recess,
40: Corner part, 41: Fixed part, 42: Arm part, 43: Connection part,
F: Filter frame, 100: Camera, 200: Portable information terminal

Claims (5)

A lens frame,
A movable support member surrounding the lens frame around the optical axis;
A leaf spring that elastically supports the lens frame on the movable support member with respect to driving in the optical axis direction;
A base support member disposed behind the movable support member;
A support wire that elastically supports the movable support member with respect to driving in a direction standing from the base support member along the optical axis and intersecting the optical axis;
A driving unit that drives the lens frame in one or both of an optical axis direction and a direction intersecting the optical axis;
The leaf spring includes a corner portion fixed to the tip of the support wire, a fixing portion fixed to the front end of the movable support member, and a pair of arm portions that elastically connect the fixing portion and the corner portion. And a connecting portion for connecting the pair of arms,
The arm portion extends from both ends of the fixed portion toward one corner, and the connecting portion is arched between a pair of the arm portions, and between the corner and the connecting portion. An opening is formed,
The front end of the movable support member is provided with a stepped portion providing a gap between the arm portion and an adhesive member reservoir recessed along the connecting portion,
The lens driving device, wherein the adhesive member stored in the adhesive member reservoir is in contact with the connecting portion. The lens driving device according to claim 1, wherein the adhesive member reservoir is disposed on the optical axis side with respect to the support wire . The lens driving device according to claim 1 , wherein the adhesive member reservoir is provided with a wall around it . The camera provided with the lens drive device described in any one of Claims 1-3 . The electronic device provided with the lens drive device described in any one of Claims 1-3 .

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