JP2016212270A - Lens drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens drive device that can prevent particles from entering into an emission side.SOLUTION: A lens drive device comprises: a movable unit that includes a lens holder holding a lens, and a drive magnet for driving the lens in an optical axis direction; and a stationary unit that includes a drive coil for driving the lens in a direction orthogonal to the optical axis direction, a base part having a base opening part transmitting light from the lens formed at a center and installing the coil, and a support part supporting the movable unit with respect to the stationary unit. In the base part, a cylindrical convex part protruding forward is formed along an opening edge of the base opening part, and a convex part front end serving as an end part forward the cylindrical convex part is located forward with respect to a coil installation face, and a coil front end is located forward from the convex part front end.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a lens driving device suitably used for a camera module of a mobile phone, for example.

  In a lens driving device suitably used for a camera module of a cellular phone, a lens driving device has been developed that performs blur correction by moving a lens holder that holds a lens in a direction orthogonal to the optical axis (for example, the following patent document) 1). The lens driving device has a base portion that supports the lens holder via a suspension wire or the like, and an opening that allows light incident on the lens to pass through is formed at the center of the base portion.

  Such a lens driving device is used with an image sensor attached to the back of the base portion. However, in the conventional lens driving device, particles (dust) flowing from the lens driving device through the opening are attached to the image sensor. However, there is a problem in that the performance of the image sensor and the quality of the image obtained from the image sensor are adversely affected.

JP 2011-65140 A

  The present invention has been made in view of such a situation, and an object thereof is to provide a lens driving device capable of preventing inflow of particles to the emission side (rear side).

In order to achieve the above object, a lens driving device according to the present invention includes:
A movable part having a lens holder for holding the lens, and a driving magnet for driving the lens in the direction perpendicular to the optical axis;
A driving coil for driving the lens in the direction orthogonal to the optical axis and a base opening for allowing the light incident on the lens to pass through are formed in the center. A fixed portion having a base portion on which the drive coil is installed;
A movable portion connected to the movable portion so as to be movable relative to the fixed portion, and a support portion for supporting the movable portion on the fixed portion,
A cylindrical convex portion that protrudes forward in a direction parallel to the optical axis direction of the lens and toward the movable portion is formed on the base portion along an opening edge of the base opening portion. And
A convex front end that is the front end of the cylindrical convex portion is located in front of a coil installation surface that is a surface on which the driving coil is installed in the base portion,
A coil front end, which is the front end of the drive coil, is located in front of the convex front end.

  In the lens driving device according to the present invention, since the cylindrical convex portion is formed along the opening edge of the base opening, even if particles are generated in the lens driving device, the particles are blocked by the cylindrical convex portion. It is done. Therefore, the lens driving device according to the present invention can prevent inflow of particles from the base opening to the image sensor side behind.

  Furthermore, the convex front end, which is the front end of the cylindrical convex, is located in front of the coil installation surface, and is located behind the coil front end, which is the front end of the driving coil. As a result, even when the movable part and the fixed part come into contact with each other due to external impact or the like, the coil is arranged closer to the movable part than the cylindrical convex part. Contact with the movable part can be prevented. Therefore, even if the movable part and the fixed part collide with each other, the collision position is on the outer peripheral side from the cylindrical convex part, so that the particles generated by the collision flow into the image sensor side through the base opening. Can be prevented.

  Further, for example, a predetermined gap may be formed between the outer peripheral side surface of the cylindrical convex portion and the driving coil.

  Even if the particles on the front surface of the driving coil move toward the base opening, such a gap is trapped in the gap, so that the particles pass through the base opening to the image sensor side. An inflow problem can be effectively prevented.

  Further, for example, a wiring connected to the driving coil may be disposed in the gap.

  By arranging the wiring connected to the driving coil in the gap, the wiring distance of the driving coil can be shortened, and the arrangement space for other members in the base portion can be increased.

Also, for example, the outer peripheral side surface of the cylindrical convex portion may have a convex flat portion that is a flat portion extending in parallel to the plane including the optical axis,
The convex portion plane portion may be a part of the outer peripheral side surface of the driving coil and face each other across the gap with respect to a coil plane portion that is a plane portion extending in parallel to the plane including the optical axis. Good.

  With this configuration, particles are easily trapped in a gap formed between the outer peripheral side surface of the cylindrical protrusion and the side surface of the driving coil. Further, when the wiring is arranged in the gap, the wiring can be prevented from deviating from the gap.

FIG. 1A is an overall perspective view of a lens driving device according to an embodiment of the present invention. FIG. 1B is an overall perspective view showing the inside of the lens driving device excluding the case shown in FIG. 1A. FIG. 1C is an overall perspective view of the lens driving device excluding the case shown in FIG. 1B as seen from different angles. FIG. 2 is an exploded perspective view of the lens driving device excluding the case shown in FIG. 1A. FIG. 3A is a perspective view of the lens holder shown in FIG. FIG. 3B is a perspective view of the lens holder shown in FIG. 3A viewed from different angles. FIG. 4 is a perspective view of the frame shown in FIG. 5A is a plan view in which the circuit board and the drive coil are arranged on the base portion shown in FIG. 2, FIG. 5B is a plan view of the first drive coil shown in FIG. 5A, and FIG. FIG. 5C is a plan view of the second drive coil shown in FIG. FIG. 6A is a perspective view of a partially assembled view in which a circuit board and a drive coil are arranged on the base portion shown in FIG. FIG. 6B is an enlarged plan view of FIG. 5A and shows the relationship between the lens and the opening. FIG. 7 is a cross-sectional view taken along line VII-VII shown in FIG. 6B, and is a cross-sectional view in which a frame and a lens holder are also combined at the upper part in the Z-axis direction of the partially assembled view shown in FIG. 6B. FIG. 8 is an enlarged cross-sectional view in which a part of FIG. 7 is enlarged.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
As shown in FIG. 1A, a lens driving device 2 according to an embodiment of the present invention includes a movable unit 3 that moves in a direction orthogonal to the optical axis together with a lens held by a lens holder 40 during blur correction. It has the fixed part 4 which produces a relative displacement with respect to the movable part 3. The fixed part 4 includes a case 11 that covers the movable part 3 from the front (Z-axis positive direction side), a base part 10 that covers the movable part 3 from the rear (Z-axis negative direction side), and the like. The base 10 and the case 11 are joined at the rear open end of the case 11 in the Z-axis direction. The connector portion 23 is a part of the circuit board 20 (see FIG. 1B) included in the fixing portion 4 and is disposed on the side surface of the lens driving device 2. The movable portion 3 is disposed inside the case 11 and includes a lens holder 40 that holds a lens, a frame 60 that holds the lens holder 40 so as to be movable in the optical axis direction, and the like. A lens not shown in FIG. 1A is attached to the inner peripheral surface 48 of the lens holder 40.

  The lens driving device 2 is used in combination with an image sensor such as a solid-state imaging device (not shown). The image sensor is arranged behind the lens holder 40 (Z-axis negative direction side), photoelectrically converts light emitted from the lens 100 held by the lens driving device 2, and generates an image. The arrangement method of the image sensor is not particularly limited, and the image sensor may be directly fixed to the base unit 10 of the lens driving device 2 or may be connected to the lens driving device 2 through another member.

  As shown in FIG. 2, inside the case 11, a circuit board 20 constituted by an FPC or the like, a blur correction coil 30 as a drive coil, a lens holder, in front of the base portion 10 in the Z-axis direction. 40, a dual-purpose magnet 80 as a drive magnet, a frame 60, and the like are arranged. The circuit board 20 and the shake correction coil 30 are part of the fixed part 4, and the dual-purpose magnet 80 and the frame 60 are part of the movable part 3.

  As shown in FIG. 2, the circuit board 20 has a substrate opening 22 penetrating the front and back surfaces at the center thereof. A cylindrical convex portion 14 formed in the central portion of the base portion 10 is inserted into the substrate opening portion 22. The cylindrical convex portion 14 is formed along the opening edge of the base opening portion 12. On the surface (front surface) of the circuit board 20, a blur correction coil 30 is mounted around the board opening 22.

  The blur correction coil 30 includes a first drive coil 30a that drives a lens in a first drive axis direction, which will be described later, and a pair of second drives that drive the lens on a second drive axis that intersects the first drive axis at a substantially right angle. A coil 30b. The first drive coil 30a and the second drive coil 30b are fixed to the surface of the circuit board 20 with an adhesive or the like.

  The circuit board 20 has a rectangular plate shape as a whole, and a connector portion 23 for connecting to an external circuit is formed on one side of the rectangular outer shape. In all the drawings, the direction parallel to the optical axis of the lens 100 (see FIG. 7, but not shown in FIG. 7) fixed to the inner peripheral surface 48 of the lens holder 40 is defined as the Z axis, and the optical axis. The description will be made with the direction perpendicular to the X-axis direction and Y-axis direction.

  Note that the X axis, the Y axis, and the Z axis are orthogonal to each other. In the present embodiment, the X axis coincides with the first drive axis, and the Y axis coincides with the second drive axis. Further, the front or front along the Z-axis means an upward direction (Z-axis positive direction) in FIGS. 2 and 7, and means a subject side with respect to the lens. Further, the rear surface or rear side along the Z-axis means a downward direction (Z-axis negative direction) in FIGS. 2 and 7, and means an image sensor (imaging device) side with respect to the lens.

  As shown in FIG. 2, the base portion 10 includes a base plate body 10a having a coil installation surface 10aa and wire rear end attachment pieces 10b attached to the four corners of the base plate body 10a. A blur correction coil 30 is installed through the circuit board 20 in front of the coil installation surface 10aa. A rear end of a single suspension wire 16 is attached to each wire rear end attachment piece 10b. The suspension wires 16 respectively extend from the four corner portions of the base portion 10 through the four corner portions of the circuit board 20 toward the front in the Z-axis direction (Z-axis positive direction). Further, the base portion 10 is formed with a base opening 12 through which light incident on the lens 100 passes, in the center of the base plate body 10a. Further, the base portion 10 has a cylindrical convex portion 14 protruding forward, which is a direction parallel to the optical axis direction and from the fixed portion 4 toward the movable portion 3, along the opening edge of the base opening portion 12. Is formed.

  The movable unit 3 includes a front spring 90, a magnetic plate 61, a focusing coil 46, a rear spring 50, and the like in addition to the lens holder 40, the dual-purpose magnet 80, and the frame 60.

  Holder attachment portions 93a to 93d of the front spring 90 are attached and fixed to the front surface 42 of the lens holder 40 shown in FIG. A sensor component 41 is attached to a part of the outer circumferential surface 47 of the lens holder 40 in the circumferential direction. The sensor component 41 is configured by, for example, a Hall IC component that detects a relative position of the lens holder 40 with respect to the frame 60 by detecting a relative movement with the Hall element (Hall magnet). A hall magnet (not shown) is attached to the inner surface of the frame 60 corresponding to the sensor component 41.

  As shown in FIGS. 1B and 2, the front spring 90 is composed of four plate-shaped split plate springs 90 a to 90 d that are separated from each other and insulated. Each of the split plate springs 90a to 90d has corner-shaped wire attachment portions 92a to 92d to which the front ends of the suspension wires 16 are attached. The suspension wire 16 and the split plate springs 90a to 90d are each made of a conductive material such as a metal, and these can be electrically connected to each other.

  The suspension wire 16 as a support part connects the front spring 90 in the movable part 3 and the base part 10 in the fixed part 4. The suspension wire 16 is freely bent and elastically deformable along drive planes including the X axis and the Y axis, respectively. Thereby, the suspension wire 16 connects the movable part 3 to the fixed part 4 so as to be movable relative to the fixed part 4, and supports the movable part 3 on the fixed part 4.

  The suspension wire 16 can be elastically deformed in the Z-axis direction when an excessive force is applied. However, in the normal lens driving operation, the suspension wire 16 is freely bent and elastically deformed. The lens 100 held by the lens holder 40 of the movable unit 3 moves along a driving plane including the X axis and the Y axis. As shown in FIG. 4, the front end of the suspension wire 16 is easily connected to the wire attachment portions 92a to 92d of the divided plate springs 90a to 90d. 62 is provided.

  Each of the split plate springs 90a to 90d has frame attachment portions 94a to 94d that are continuous with the corner-like wire attachment portions 92a to 92d. Each frame attaching part 94a-94d is attached and fixed to four corner | angular parts located in the front surface 64 of the frame 60 of the square ring shape shown, for example in FIG. The frame 60 itself is made of an insulating material such as plastic.

  A plurality of mounting convex portions 65 are preferably formed on the front surface 64 located at the corner of the frame 60. Each mounting convex portion 65 is fitted into a fitting hole formed in the frame mounting portions 94a to 94d of the split leaf springs 90a to 90d shown in FIGS. 1B and 2. The divided leaf springs 90a to 90d are positioned and fixed to the frame 60 in this way.

  Holder attachment portions 93a to 93d are connected to the frame attachment portions 94a to 94d of the divided plate springs 90a to 90d through meandering portions 95a to 95d, respectively. The holder attachment portions 93a to 93d are formed with fitting holes, respectively. As shown in FIGS. 2 and 3A, mounting convex portions 43a to 43d are formed substantially uniformly along the circumferential direction on the front surface 42 of the lens holder 40, and the holder mounting portions in the divided leaf springs 90a to 90d are formed. In 93a to 93d, fitting holes are formed corresponding to the mounting convex portions 43a to 43d. The split plate springs 90a to 90d are fixed to the front surface 42 of the lens holder 40 by adhesion or the like in a state where the mounting convex portions 43a to 43d of the lens holder 40 are inserted into the fitting holes.

  That is, when the meandering portions 95a to 95d are elastically deformed, the front spring 90 is moved in the direction of the optical axis with respect to the frame 60 by the holder mounting portions 93a to 93d formed at the inner peripheral ends thereof. It is held movably in the Z-axis direction.

  In addition, each of the split plate springs 90 a to 90 d of the front spring 90 is connected to a separate suspension wire 16 and connected to a wiring pattern formed on the front surface of the lens holder 40. Therefore, it is possible to supply a drive current to the focusing coil 46 held by the lens holder 40 through the suspension wire 16 and the front spring 90 and to transmit a detection signal detected by the sensor component 41 to the circuit board 20. Yes. Each suspension wire 16 can be electrically connected to the wiring pattern of the circuit board 20.

  As shown in FIG. 3B, arc-shaped leaf spring mounting portions 44a and 44b are formed on the rear surface 45 of the lens holder 40. A stepped portion 49 is formed on the rear side of the outer peripheral surface 47 of the lens holder 40. A square ring-shaped focusing coil 46 shown in FIG. 2 is fixed to the step portion 49.

  As shown in FIG. 2, the rear spring 50 is composed of a pair of split leaf springs 50a and 50b. Each split leaf spring 50a, 50b is formed with arcuate holder mounting portions 54a, 54b on the inner periphery thereof. Each holder attaching part 54a, 54b is fixed to the leaf spring attaching part 44a, 44b shown in FIG. 3B. The means for fixing the rear spring 50 to the leaf spring mounting portions 44a and 44b is not particularly limited, and examples include fixing by fitting and fixing by an adhesive.

  As shown in FIG. 2, meandering portions 55a and 55b are formed on the split plate springs 50a and 50b of the rear spring 50 continuously from both end portions of the holder mounting portions 54a and 54b. Frame mounting portions 52a and 52b are formed continuously on the outer peripheral side of 55b. Each frame attachment portion 52a, 52b is fitted and fixed to the corner rear surface 68 of the frame 60.

  That is, the rear spring 50 is similar to the front spring 90 in that the meandering portions 55a and 55b are elastically deformed so that the lens holder 40 is attached to the frame 60 by the holder mounting portions 54a and 54b formed at the inner peripheral ends. On the other hand, it is held movably in the Z-axis direction, which is the optical axis direction. However, unlike the front spring 90, the rear spring 50 does not need to have a function of an electrical conduction path.

  As shown in FIG. 4, magnet mounting recesses 66 are formed along the four sides of the square on the rear side in the Z-axis direction of the square ring-shaped frame 60. As shown in FIG. 2 and FIG. 7, a dual-purpose magnet 80 is fixed to the magnet mounting recess 66 via a magnetic plate 61.

  As shown in FIG. 7, the blur correction coil 30 is disposed so as to face the dual-purpose magnet 80. In a state where a strong external force is not applied to the lens driving device 2, the rear surface of the dual-purpose magnet 80 and the front surface of the shake correction coil 30 are opposed to each other with a predetermined interval in the Z-axis direction. The blur correction coil 30 and the dual-purpose magnet 80 constitute a voice coil motor that drives the lens 100 held by the lens holder 40 in the movable portion 3 in the direction orthogonal to the optical axis.

  That is, by applying a drive current to the shake correction coil 30, a force in the direction perpendicular to the optical axis acts on the dual purpose magnet 80 due to the cooperative action of the blur correction coil 30 and the dual purpose magnet 80. Here, since the frame 60 to which the dual-purpose magnet 80 is fixed holds the lens holder 40 via the front spring 90 and the rear spring 50, the force acting on the dual-purpose magnet 80 is a force that moves the lens holder 40. It becomes. In this way, the lens driving device 2 includes the movable portion 3 including the lens holder 40 and the dual-purpose magnet 80 with respect to the fixed portion 4 including the base portion 10 and the shake correction coil 30. It can be moved along the drive plane. By moving the lens 100 along the driving plane together with the lens holder 40, the lens driving device 2 can perform the blur correction operation.

  Further, as shown in FIG. 7, the focusing coil 46 is also arranged so as to face the dual-purpose magnet 80. The inner peripheral surface of the dual-purpose magnet 80 and the outer peripheral surface of the focusing coil 46 are opposed to each other at a predetermined interval in the direction perpendicular to the optical axis. The focusing coil 46 and the dual-purpose magnet 80 constitute a voice coil motor that drives the lens 100 held by the lens holder 40 in the optical axis direction.

  That is, by applying a drive current to the focusing coil 46, a force in the optical axis direction acts on the focusing coil 46 by the cooperative action (VCM action) of the focusing coil 46 and the dual-purpose magnet 80. Therefore, the lens driving device 2 can move the lens holder 40 and the lens 100 back and forth in the optical axis direction with respect to the frame 60 and the fixed portion 4. The lens driving device 2 can perform an autofocus (AF) operation by moving the lens 100 together with the lens holder 40 in the optical axis direction with respect to the frame 60 and the fixed portion 4.

  In the present embodiment, the dual-purpose magnet 80 serves as both an AF control magnet and a shake correction control magnet, so that the number of parts can be reduced, and AF control and shake correction control can be performed with a simple configuration. Become. In addition, the lens driving device 2 can be reduced in size. However, the driving magnet used in the lens driving device 2 is not limited to the dual-purpose magnet 80, and may be a magnet dedicated to shake correction.

  The lens 100 may be composed of a plurality of lens groups. However, in the present embodiment, the description will be made assuming that the lens 100 is composed of one lens for the sake of simplicity.

  As shown in FIGS. 6A and 6B, the blur correction coil 30 includes a pair of first drive coils 30a and 30a that face each other with the base opening 12 sandwiched along the X-axis direction, and a base opening along the Y-axis direction. And a pair of second drive coils 30b and 30b facing each other with the portion 12 interposed therebetween. The first and second drive coils 30a and 30b installed on the base portion 10 via the circuit board 20 have a base portion so as to surround the cylindrical convex portion 14 in front of the square plate-shaped base portion 10 as a whole. 10 are arranged in parallel along each side.

  The positions of the first drive coils 30a, 30a facing each other along the X axis are slightly shifted in the Y axis direction, and the second drive coils 30b, 30b facing each other along the Y axis. The arrangement position in the X-axis direction is also slightly shifted. As described above, the first and second drive coils 30a and 30b are displaced in the same direction along the circumferential direction because the position sensors 18a and 18b and the damper base are placed at the four corners of the base 10 and the circuit board 20. This is because the suspension wire 16 can be easily fixed and passed through while being easily mounted.

  The position sensor 18a is constituted by a Hall sensor, for example, and faces the rear surface of one first drive magnet 80a of the dual-purpose magnet 80 shown in FIG. 2 together with one first drive coil 30a at a predetermined interval. The moving position in the X-axis direction can be detected. Further, the position sensor 18b is composed of, for example, a Hall sensor, and faces the rear surface of one second drive magnet 80b of the dual-purpose magnet 80 shown in FIG. 2 together with one second drive coil 30b at a predetermined interval. The movement position in the Y-axis direction of 80b can be detected. These position sensors 18 a and 18 b are electrically connected to the wiring pattern of the circuit board 20.

  In the present embodiment, the first drive coil 30a and the first drive magnet 80a are arranged at a predetermined interval along the Z-axis direction to constitute a first drive unit (first VCM) for blur correction, and the second The drive coil 30b and the second drive magnet 80b are arranged at a predetermined interval along the Z-axis direction and constitute a second drive unit (second VCM) for blur correction. The first drive axis of the first drive unit is the X axis, and the second drive axis of the second drive unit is the Y axis.

  The damper base 24 shown in FIGS. 6A and 6B is fixed to the four corners of the circuit board 20 by means such as adhesive or brazing. As shown in FIG. 1C, a predetermined damper gap is formed between the front surface of the damper base 24 and the corner rear surface 68 or the rear surface convex portion 69 of the frame 60, and a gel-like gap is formed in the damper gap. The damper material 70a is interposed so as to be in close contact with both. The damper gap is made larger than the interval between the dual-purpose magnet 80 and the shake correction coil 30, and specifically, about 0.1 to 0.4 mm is preferable.

  The damper material 70a is composed of a vibration absorbing material such as a soft gel material or a soft adhesive, but the material of the damper material 70a is not particularly limited. The damper material 70a functions as a damper when the frame 60 moves along the driving plane including the X axis and the Y axis with respect to the base portion 10 and the circuit board 20, and an effect of suppressing vibration can be expected.

  In the present embodiment, the damper material 70 a is not provided between the dual-purpose magnet 80 and the shake correction coil 30, but between the damper base 24 and the corner rear surface 68 of the frame 60, or on the rear surface of the damper base 24 and the frame 60. It is interposed between the part 69. For this reason, in this embodiment, even if an impact such as a drop of a portable device including the lens driving device 2 is applied, the combined function of the combined magnet 80 and the shake correction coil 30 causes the stopper action to function. . Therefore, the damper material 70a maintains the state in which the damper material 70a is held between the damper base 24 and the corner rear surface 68 of the frame 60 or between the damper base 24 and the rear surface convex portion 69 of the frame 60. The damper characteristics can be maintained well even after impact.

  In the present embodiment, as shown in FIG. 7, a part of the lens 100 is inserted into the base opening portion 12 of the base portion 10. As shown in FIG. 6B, in this embodiment, the oblique inner diameters Dxy1 and Dxy2 of the oblique base opening 12 located between the first drive shaft (X axis) and the second drive shaft (Y axis) The opening 12 is larger than the first inner diameter Dx in the X-axis direction and larger than the second inner diameter Dy of the base opening 12 in the Y-axis direction.

  In the present embodiment, the first inner diameter Dx and the second inner diameter Dy are substantially equal. The oblique inner diameters Dxy1 and Dxy2 are substantially equal to each other. The positions of the slanted inner diameters Dxy1 and Dxy2 are not particularly limited, and may be larger than the first inner diameter Dx and the second inner diameter Dy at any position between the first drive shaft (X axis) and the second drive shaft (Y axis). In particular, it is preferable that it is larger than the first inner diameter Dx and the second inner diameter Dy near the bisector of the intersection angle between the straight line along the first inner diameter Dx and the straight line along the second inner diameter Dy. .

  In the present embodiment, the base opening 12 is, for example, an n-polygonal polygonal shape, but the inner peripheral surface shape of the base opening 12 is not limited to a polygonal shape, and may be a curved surface shape. In addition, the maximum value of the oblique inner diameters Dxy1 and Dxy2 is preferably 1.02 to 1.05 times the first inner diameter Dx or the second inner diameter Dy.

  In the lens driving device 2 according to the present embodiment, as illustrated in FIG. 6B, the oblique inner diameters Dxy1 and Dxy2 of the oblique base opening 12 located in the middle of the X axis and the Y axis are the X axis of the base opening 12. It is larger than the first inner diameter Dx in the direction and larger than the second inner diameter Dy in the Y-axis direction of the base opening 12. With this configuration, not only when the lens 100 moves in the X-axis direction or the Y-axis direction but also when the lens 100 moves in an oblique direction between them, the lens 100 moves the opening edge of the base opening 12. There is no possibility of colliding with the inner peripheral surface of the cylindrical convex portion 14 to be configured. That is, the maximum movement amount of the lens 100 in the oblique direction is obtained by dividing the maximum movement amount in the first and second drive shaft directions by the cosine of the included angle (0 to 90 °) formed between the drive shaft and the oblique direction. Whichever is smaller, which is larger than the maximum movement amount in the first or second drive shaft direction. However, by setting the oblique inner diameters Dxy1 and Dxy2 to be larger than the first inner diameter Dx and the second inner diameter Dy, the distance between the circular lens 100 and the opening edge becomes larger in the oblique direction. Can be prevented from colliding with the opening edge.

  Moreover, in the lens driving device 2 according to the present embodiment, the base opening 12 formed in the base portion 10 is not a perfect circle, and the inner diameter Dxy1, which is an oblique direction located in the middle of the X-axis direction or the Y-axis direction. It has an irregular shape with a large Dxy2. Therefore, the outer shape of the base portion 10 can be reduced as compared with a perfect base opening in consideration of the maximum amount of movement in the oblique direction, which contributes to downsizing of the apparatus. In particular, as shown in FIG. 6B, since the first inner diameter Dx and the second inner diameter Dy are smaller than the oblique inner diameters Dxy1 and Dxy2, there is a sufficient space in the X-axis and Y-axis directions in which the blur correction coils 30 are arranged. Accordingly, the lens driving device 2 is provided with the first and second driving coils 30a and 30b that are larger in size and larger in driving force than the conventional one without increasing the outer shape of the base portion 10 and the circuit board 20, and the blur correction performance. On the contrary, by increasing only the slanted inner diameters Dxy1 and Dxy2, the lens 100 having a larger diameter than the conventional one can be held by the lens holder 40.

  Furthermore, in the present embodiment, the first drive unit includes a pair of first drive coils 30a located on both sides of the base opening 12 along the X-axis direction, and the pair of first drive coils 30a includes the base unit. 10 are arranged in parallel along two opposing sides. With this configuration, the driving force along the X-axis direction is improved, and the accuracy of blur correction is improved.

  The second drive unit includes a pair of second drive coils 30b located on both sides of the base opening 12 along the Y-axis direction, and the pair of second drive coils 30b are opposed to the base unit 10. They are arranged in parallel along the two sides. With this configuration, the driving force along the Y-axis direction is improved and the accuracy of blur correction is improved.

  Further, as shown in FIG. 1B, the frame 60 has a square ring shape as a whole, and is disposed inside the rectangular tube-shaped case 11 fixed to the base portion 10. Corresponds to the oblique direction defining the oblique inner diameters Dxy1 and Dxy2 shown in FIG. 6B. With this configuration, as shown in FIG. 6B, the first drive coil 30a and the second drive coil 30b can be efficiently arranged on the base portion 10 excluding the base opening portion 12. The outer shape of the base portion 10 can be reduced, and the lens driving device 2 can be easily downsized.

  Furthermore, in this embodiment, as shown in FIG. 6B, a cylindrical convex portion 14 is formed on the base portion 10 along the opening edge of the base opening portion 12. As shown in FIG. 8, which is an enlarged view of FIG. 7, a coil arrangement surface 10 aa that is a surface on which the blur correction coil 30 is installed is provided on the outer peripheral side of the cylindrical convex portion 14. The coil installation surface 10aa is formed on a surface facing forward in the base portion 10, and the first drive coil 30a and the second drive coil 30b are installed on the coil arrangement surface 10aa via the circuit board 20. .

  The cylindrical convex portion 14 projects forward from the coil installation surface 10aa, and the convex front end 14a, which is the front end portion of the cylindrical convex portion 14, is positioned forward of the coil installation surface 10aa of the base portion 10. Further, the coil front end 30c, which is the front end portion of the blur correction coil 30 (the first drive coil 30a in FIG. 8) disposed on the coil installation surface 10aa, is forward of the convex front end 14a of the cylindrical convex portion 14. To position.

  In the lens driving device 2 having such a cylindrical convex portion 14, even when particles are generated in the lens driving device 2, the particles are blocked by the cylindrical convex portion 14. Therefore, the lens driving device 2 can prevent particles generated by the lens driving device 2 from flowing into the rear image sensor side via the base opening 12. If particles or the like adhere to the light receiving surface of the image sensor, the quality of the image generated by the image sensor may be reduced, and if the particle is a conductive material, the image sensor may be damaged. Such a problem can be prevented by the cylindrical convex portion 14.

  Further, since the convex front end 14a of the cylindrical convex portion 14 is located behind the coil front end 30c of the blur correction coil 30, the movable part 3 and the fixed part 4 come into contact with each other due to external impact or the like. Even if it is a case, it can prevent that the cylindrical convex part 14 contacts the movable part 3 directly by the coil front end 30c contacting the combined magnet 80, and receiving an impact. Therefore, even if the movable portion 3 and the fixed portion 4 collide with each other due to an external impact or the like, the lens driving device 2 has a collision position on the outer peripheral side from the cylindrical convex portion 14, so that particles generated by the collision are not generated. The problem of flowing into the image sensor through the base opening 12 can be prevented.

  Further, in the lens driving device 2, as shown in FIG. 8, a gap 15 having a predetermined width is formed between the outer peripheral side surface 14 b of the cylindrical convex portion 14 and the shake correction coil 30. By providing such a gap 15, even when the particles move along the coil front end 30 c of the shake correction coil 30 toward the base opening 12, the particles are trapped in the gap 15. Is done. Therefore, the lens driving device 2 in which such a gap 15 is formed can more effectively prevent particles from flowing into the base opening 12. As shown in FIG. 7, when the diameter of the lens 100 is increased, the opening area of the base opening 12 is also increased, so that the inflow of particles to the image sensor side tends to easily occur. The lens driving device 2 that can prevent inflow is particularly suitable as a lens driving device that holds the large-diameter lens 100.

  As shown in FIG. 6B, in the lens driving device 2, the total area of the coil front end 30c including the four shake correction coils 30 is the area of the convex front end 14a in order to secure a driving force for shake correction. It is getting wider. Since the lens driving device 2 has a structure in which the impact of the collision between the movable portion 3 and the fixed portion 4 is received by the coil front end 30c having a larger area than the convex front end 14a, particles are generated by a large external force acting in a narrow range. Can prevent problems. Further, the damper material 70a shown in FIG. 1C also acts as a buffer material that softens the impact generated when the movable portion 3 and the fixed portion 4 collide, and suppresses the generation of particles in the lens driving device 2.

  Further, as shown in FIGS. 5A to 5C, in the lens driving device 2, a wire wiring 32a as a wiring portion connected to the pair of first driving coils 30a and a pair of second driving coils 30b. A wire wiring 32 b as a wiring portion connected to the wire is disposed in a gap 15 formed between the outer peripheral side surface of the cylindrical convex portion 14 and the shake correction coil 30. By arranging the wire wirings 32 a and 32 b connected to the shake correction coil 30 in the gap 15, the wiring distance of the shake correction coil 30 can be shortened, and the arrangement space for other members in the base portion 10 is increased. be able to. Further, the lead wires 34a and 34b of the drive coils 30a and 30b are connected to the circuit pattern of the circuit board 20 by effectively using the corner space between the cylindrical convex portion 14 and the drive coils 30a and 30b. Is easy. In other drawings except FIGS. 5A to 5C, the wire wirings 32a and 32b are not shown.

  As shown in FIG. 5A, the outer peripheral shape of the cylindrical convex portion 14 is a polygonal shape like the base opening 12, and the outer peripheral side surface 14b of the cylindrical convex portion 14 is a plane extending parallel to the plane including the optical axis. It has the convex part plane part 14ba which is a part. Convex portion flat portions 14ba extending parallel to the plane including the optical axis are formed at four locations on the outer peripheral side surface 14b of the cylindrical convex portion 14. Each of the convex flat portions 14ba is a part of the outer peripheral side surface of the shake correction coil 30 and is a flat portion extending in parallel with the plane including the optical axis, with the gap 15 interposed therebetween. Facing each other.

  Since such a convex portion flat portion 14ba is formed, the lens driving device 2 can easily arrange the wire wirings 32a and 32b along the outer peripheral side surface 14b of the cylindrical convex portion 14, and can also provide impact. For example, the wire wirings 32a and 32b can be prevented from deviating from the gap 15. In addition, by forming a gap 15 having a predetermined width along the X-axis and Y-axis directions around the cylindrical convex portion 14, particles are easily trapped in the gap 15, and the base opening The inflow of particles to the portion 12 can be more effectively prevented.

  The present invention is not limited to the above-described embodiment, and can be variously modified. For example, in the above-described embodiment, the driving force of the shake correction coil 30 is increased by fixing the driving coils 30a and 30b to the surface of the circuit board 20, but there is no need to increase the driving force. For this, a circuit board in which a coil is embedded may be used.

  In the above-described embodiment, the first drive shaft and the second drive shaft are arranged in parallel to the sides of the square plate-shaped base portion 10 and the circuit board 20, but the present invention is not limited thereto. For example, the first drive coil 30a and the second drive coil 30b may be arranged so that the first drive shaft and the second drive shaft are positioned on the diagonal line of the square plate-shaped base portion 10 and the circuit board 20. .

  Further, in the above-described embodiment, the single dual-purpose magnet 80 has the two functions of the shake correction magnet and the autofocus magnet. However, separate magnets may be prepared and attached. .

  Furthermore, in the above-described embodiment, the lens driving device 2 has two mechanisms, that is, an autofocus mechanism and a shake correction mechanism. However, the lens drive device of the present invention only needs to have at least a shake correction mechanism.

  In the above-described embodiment, the intersection angle between the first drive shaft and the second drive shaft is 90 degrees. However, in the present invention, these intersection angles may be other than 90 degrees.

DESCRIPTION OF SYMBOLS 2 ... Lens drive device 3 ... Movable part 4 ... Fixed part 10 ... Base part 11 ... Case 12 ... Base opening part 14 ... Cylindrical convex part 16 ... Suspension wire 18a, 18b ... Position sensor 20 ... Circuit board 22 ... Substrate opening part DESCRIPTION OF SYMBOLS 23 ... Connector part 24 ... Damper base 30 ... Shake correction coil 30a ... 1st drive coil 30b ... 2nd drive coil 30c ... Coil front end 30d ... Coil plane part 40 ... Lens holder 41 ... Sensor component 42 ... Front 43a-43d ... Mounting convex portions 44a, 44b ... Plate spring mounting portion 45 ... Rear surface 46 ... Focusing coil 47 ... Outer peripheral surface 48 ... Inner peripheral surface 49 ... Stepped portion 50 ... Rear springs 50a, 50b ... Split plate springs 52a, 52b ... Frame mounting Portions 54a, 54b ... Holder mounting portions 55a, 55b ... Meandering portion 60 ... Frame 61 ... Magnetic plate 62 ... notch 64 ... front 65 ... mounting convex 66 ... magnet mounting concave 68 ... corner rear surface 69 ... rear convex 70a ... damper material 80 ... dual-purpose magnet 80a ... first drive magnet 80b ... second drive magnet 90 ... Front springs 90a-90d ... Split plate springs 92a-92d ... Wire attachment parts 93a-93d ... Holder attachment parts 94a-94d ... Frame attachment parts 95a-95d ... Meandering part 100 ... Lens

Claims (4)

A movable part having a lens holder for holding the lens, and a driving magnet for driving the lens in the direction perpendicular to the optical axis;
A driving coil for driving the lens in the direction orthogonal to the optical axis and a base opening for allowing the light incident on the lens to pass through are formed in the center. A fixed portion having a base portion on which the drive coil is installed;
A movable portion connected to the movable portion so as to be movable relative to the fixed portion, and a support portion for supporting the movable portion on the fixed portion,
A cylindrical convex portion that protrudes forward in a direction parallel to the optical axis direction of the lens and toward the movable portion is formed on the base portion along an opening edge of the base opening portion. And
A convex front end that is the front end of the cylindrical convex portion is located in front of a coil installation surface that is a surface on which the driving coil is installed in the base portion,
The lens driving device according to claim 1, wherein a front end of the coil, which is the front end of the driving coil, is positioned in front of the front end of the convex portion.   The lens driving device according to claim 1, wherein a predetermined gap is formed between an outer peripheral side surface of the cylindrical convex portion and the driving coil.   The lens driving device according to claim 2, wherein a wiring connected to the driving coil is disposed in the gap. The outer peripheral side surface of the cylindrical convex portion has a convex plane portion that is a plane portion extending in parallel to the plane including the optical axis,
The convex flat portions face each other across the gap with respect to a coil flat portion which is a part of the outer peripheral side surface of the driving coil and extends in parallel to the plane including the optical axis. The lens driving device according to claim 2 or claim 3.

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