JP2016014705A - Lens driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens driving device sharing a magnet opposed to a position sensor of a movable part with a driving part and having a hand shake correcting function suppressing rotational movement of the movable part.SOLUTION: A lens driving device 1 has a driving magnet 15 and a driving coil 14 arranged so that a magnetic boundary line of the magnet 15 coincides with a long axis of the driving coil 14. In coil position regulators 31A and 31B of the driving coil 14 of a base member 3, a position sensor is arranged so that the respective centers of the magnet 15 and the position sensor 16 correspond to each other. At each side of the position sensor, an adhesive member 18 is arranged so that the center thereof is on the magnetic boundary line.

Description

  The present invention relates to a lens driving device mounted on an electronic device such as a mobile phone, and more particularly to a lens driving device having a camera shake correction function.

Conventionally, there are JP 2009-145771 A and JP 2014-85560 A as technologies in such fields. This gazette discloses a camera shake correction device used for a camera. This camera shake correction apparatus relates to a correction optical apparatus for correcting image shake, and particularly includes a correction optical apparatus including a magnetic actuator having a voice coil configuration.
In patent document 1, the damping means which suppresses the resonance of a movable member is provided.
In Patent Document 2, a position sensor and a dedicated position detection magnet are arranged to detect the movement position of the correction lens frame in the X direction and the Y direction.

JP 2009-144771 A JP 2014-85560 A

However, the damping means of the camera shake correction apparatus of Patent Document 1 is disposed at a position away from the magnetic actuator. Further, since the damping means has a characteristic of suppressing resonance, it slightly acts as a resistance when the movable part moves. Therefore, when the movable part moves, a force that the movable part tries to rotate around the damping means acts, making it difficult to instantaneously move the movable member to the target position.
Further, in Patent Document 2, a magnet facing the position detection sensor is required in addition to the magnet provided in the magnetic actuator, which is disadvantageous in reducing the space and increasing the cost.

  The present invention has been made in view of the above problems, and suppresses the rotation of the movable part, eliminates a dedicated magnet for position detection, and has a lens driving device having a camera shake correction function advantageous for space and cost, and An object of the present invention is to provide a camera and an electronic device incorporating a lens driving device.

  A lens driving device according to the present invention includes a lens frame, a base member, and a support unit that supports the lens frame so that the lens frame can move in a direction intersecting the optical axis, and the lens frame intersects the optical axis. The drive means is composed of a magnetic circuit using at least one pair of magnets and a drive coil, and the position of the adhesive member and the lens frame is detected at the air core of the coil. A position sensor is arranged to face the magnet.

  The driving means includes two sets of magnets and a driving coil. The driving member includes a coil as a base member and a magnet fixed to the lens frame. The adhesive member and the position sensor are fixed to the base member.

The coil has a major axis and a minor axis, and the center of the magnet and the center of the position sensor are substantially coincident with the center where the major axis and the minor axis of the coil intersect, and the adhesive member extends in the major axis direction of the drive coil. The position sensor is arranged at two positions.
Furthermore, the magnetization boundary line of the magnet and the major axis direction of the coil coincide with each other, and the center position of the two adhesive members is on the magnetization boundary line.

  Further, the lens frame may be supported so as to be movable in the optical axis direction and the direction intersecting the optical axis, and may include driving means for driving the lens frame in the optical axis direction and the direction orthogonal to the optical axis.

  The lens driving device according to the present invention provides a lens driving device that can reduce the number of magnets and prevent rotation of a movable part.

It is a disassembled perspective view which shows schematic structure of the lens drive device which concerns on embodiment of this invention. It is a top view which shows the base member of the lens drive device which concerns on embodiment of this invention. It is a top view which shows the base member by which the magnet of the lens drive device which concerns on embodiment of this invention is arrange | positioned. It is a partial expanded sectional view of the drive coil arrangement | positioning part and position sensor arrangement | positioning part which show embodiment of this invention. It is a figure which shows the camera which incorporated the lens drive device of this invention. It is a figure which shows the electronic device which incorporated the lens drive device of this invention.

  A lens driving device according to an embodiment of the present invention includes a lens frame, a base member, and a support unit that supports the lens frame with respect to the base member so as to be movable in an optical axis direction and a direction intersecting the optical axis. In addition, driving means for driving the lens frame in the optical axis direction and in a direction orthogonal to the optical axis is provided.

  The driving means includes first to third driving means. The first driving means drives the support portion in the optical axis direction. The second drive means and the third drive means include a coil and a magnet, and a magnetic circuit is formed between the coil and the magnet when the coil is energized to drive the support portion in a direction orthogonal to the optical axis.

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the same portions are denoted by the same reference numerals, and a part of overlapping explanation for each drawing is omitted. 1 to 4 are views showing an embodiment of the present invention, FIG. 1 is an exploded perspective view, FIG. 2 is a plan view showing a base member, and FIG. 3 is a plan view of the base member to which a magnet is attached. 4 is a partially enlarged cross-sectional view of the coil placement portion. 5 and 6 show a product incorporating the lens driving device of the present invention, FIG. 5 is a camera incorporating the lens driving device of the present invention, and FIG. 6 is an electronic device incorporating the lens driving device of the present invention. Shows the equipment.

As shown in FIGS. 1 to 4, the lens driving device 1 includes a lens frame 2, a base member 3, a support portion 4, a driving means 7, and a cover member 17.
The lens frame 2 includes a lens attachment opening 2A to which a lens barrel (not shown) is attached. The lens frame 2 is supported by the base member 3 via the support portion 4.

  In FIG. 1, the support portion 4 includes a magnet holder 11, a first elastic support member 5, and a second elastic support member 6. The magnet holder 11 is a resin member surrounding the periphery of the lens frame 2 and is configured by a short frame member in the illustrated example, and magnets 15 (15A, 15B, 15C, 15D) which are constituent elements of the driving means are provided at the four corners. ) Is attached.

  The first elastic support member 5 elastically supports the lens frame 2 along the optical axis direction with respect to the magnet holder 11, and is constituted by upper plate springs 5A and 5B and a lower plate spring 5C.

  The upper leaf spring 5A includes a lens frame attachment portion 5A1, magnet holder attachment portions 5A2, 5A3, wire column attachment portions 5A4, 5A5, and an elastic deformation portion 5A6, and the upper leaf spring 5B includes a lens frame attachment portion 5B1 and a magnet holder attachment. Part 5B2, 5B3, wire pillar attaching part 5B4, 5B5, and elastic deformation part 5B6 are provided. The lens frame mounting portions 5A1 and 5B1 of the upper plate springs 5A and 5B are mounted on the upper end mounting portion 2B of the lens frame 2, and the magnet holder mounting portions 5A2, 5A3, 5B2 and 5B3 of the upper plate springs 5A and 5B are magnets. The holder 11 is attached to the upper edge 11A. The lower leaf spring 5C includes a pair of lens frame attachment portions 5C1, 5C1, a magnet holder attachment portion 5C2, and an elastic deformation portion 5C3. The lens frame attachment portion 5C1 is attached to the lower end attachment portion 2C of the lens frame 2. The magnet holder attaching portion 5C2 is attached to the lower edge 11B of the magnet holder 11.

The second elastic support member 6 elastically supports the magnet holder 11 with respect to the base member 3 along the direction intersecting the optical axis. In the illustrated example, the plurality of wire pillars 6A, 6B, 6C, and 6D are used. It is configured. The plurality of wire pillars 6A, 6B, 6C, and 6D are attached to the wire pillar attachment parts 5A4, 5A5, 5B4, and 5B5 of the upper plate springs 5A and 5B whose upper ends are attached to the magnet holder 11. Are mounted in insertion holes 3G provided at the four corners of the base member 3. The wire columns 6A, 6B, 6C, 6D support the lens frame 2, the magnet holder 11, and the first elastic support member 5 in a suspended manner on the base member 3, and the wire columns 6A, 6B, 6C, 6D The lens frame 2 or the magnet holder 11 can be moved in a direction intersecting the optical axis Oa by elastic bending.

The driving means 7 includes a first coil 13 and a second coil 14 (14A, 14B, 14C, 14D).
The magnets 15 (15A, 15, 15, 15D) constitute first to third electromagnetic actuators. The first coil 13 is wound around a coil holding portion 2D1 on the side surface 2D of the lens frame 2 and cooperates with the magnet 15 (15A, 15B, 15C, 15D) attached to the magnet holder 11 to thereby form the lens frame 2. Is configured along the optical axis Oa. In FIG. 1, only a part of the first coil 13 is shown. One side of the magnet 15 (15A, 15B, 15, 15D) facing the lens frame 2 is either the N or S pole, and the back side thereof is magnetized to the other pole. Plate-shaped yokes 12A, 12B, 12C, and 12D are arranged on the back side of the magnet 15 (15A, 15, 15, 15D).

  The second coils 14 (14 </ b> A, 14 </ b> B, 14 </ b> C, 4 </ b> D) have air core portions held by the two coil holding portions 3 </ b> E and two coil holding portions 3 </ b> G in the base member 3, respectively, and are attached to the magnet holder 11. In cooperation with the magnet 15 (15A, 15B, 15C, 15D), a second electromagnetic actuator 91A and a third electromagnetic actuator 91B are configured to drive the magnet holder 11 including the lens frame 2 in a direction orthogonal to the optical axis Oa. ing. In FIG. 2, the second coils 14A, 14B, 14C, and 14D are wound in an oval shape having a major axis and a minor axis, and the four major axes are substantially the same in a plane orthogonal to the optical axis Oa. They are arranged in different directions so as to form a right angle. And the magnet 15 (15A, 15B, 15C, 15D) is such that the magnetization boundary line between the N pole and the S pole coincides with the long axis of the coil, and the left and right sides are even with respect to the short axis of the coil. In other words, in other words, the magnet 15 and the second coil 14 are arranged to face each other so that the center of the magnet 15 coincides with the center where the major axis and the minor axis of the second coil 14 intersect.

  The base member 3 includes an opening 3 </ b> A that faces the lens mounting opening 2 </ b> A of the lens frame 2. It is formed in a short shape corresponding to the magnet holder 11, and through holes 3G for supporting the wire pillars 6A, 6B, 6C, 6D are formed at the four corners thereof. Further, the position sensor holding portion 3F is provided together with the above-described coil holding portion 3E, and a contact protrusion with which the lower end of the lens frame 2 contacts is provided. The two position sensor holding portions 3F are respectively installed so that the center position where the major axis and the minor axis of the second coil 14 (14A, 14B) intersect and the center position of the position sensor 16 coincide. The two position sensors 16 are also arranged to face the magnets 15A and 15B attached to the magnet holder 11 so that the centers of the magnets 15A and 15B coincide.

  In the coil position restricting portions 31A and 31B of the base member 3, a concave adhesive member reservoir 19 is formed on the top surface 3L facing the magnet 15 so as to sandwich the position sensor holding portion 3F in the major axis direction of the second coil. ing. The center of the adhesive member reservoir 19 is disposed on the magnetization boundary line (on the long axis of the second coil), and the adhesive member 18 is disposed in the recess.

  As shown in FIG. 1, the lens driving device 1 can be provided with a cover member 17 that covers the lens frame 2, the support portion, and the driving means and has an electromagnetic shielding function. The cover member 17 can be provided with another mechanism such as a shutter mechanism on the upper portion provided with the optical path opening 17A. It is possible to supply power to the driving means of such another mechanism from the connection terminal of the base member 3 by providing a wiring along the cover member 17, for example.

  Next, the operation of the camera shake correction mechanism of the lens driving device 1 will be described. If camera shake occurs when photographing with a device (for example, a camera) in which the lens driving device 1 is incorporated, the position of the optical axis Oa changes. In this case, a detection sensor that detects camera shake such as a gyro sensor detects camera shake, and the control means (not shown) controls the second coil so that the position of the optical axis Oa on the image sensor is maintained at a predetermined position. 14 (14A, 14B, 14C, 14D) is energized. At this time, the second electromagnetic actuator 91A and the third electromagnetic actuator 91B form a magnetic field between the second coil 14 (14A, 14B, 14C, 14D) and the magnet 15 (15A, 15B, 15C, 15D). A driving force is generated in the magnet holder 11 including the lens frame 2. As a result, the magnet holder 11 including the lens frame 2 is driven in the direction of F1 or F2 in a plane orthogonal to the optical axis. The magnet holder 11 including the lens frame 2 is supported by four wire pillars 6A, 6B, 6C, 6D so as to be movable in a direction substantially orthogonal to the optical axis direction, and the position of the optical axis Oa corrects camera shake. It is moved to a predetermined position as much as possible. By this movement, the position of the optical axis Oa on the image sensor is maintained at a predetermined position, and camera shake can be corrected.

Here, the two position sensors 16 arranged to detect the position in which direction the magnet holder 11 has moved are detecting the strength of the magnets 15A and 15B.
At this time, the change in position of the optical axis Oa caused by camera shake may move in either direction of 360 degrees around the optical axis Oa. Therefore, the magnets 15A and 15B and the position sensor 16 need to face each other regardless of the direction of movement, and the centers of the magnets 15A and 15B and the position sensor 16 can always face each other at the same moving distance. Are arranged to match. This is because if the center positions do not match, there is a possibility that the position cannot be detected because the magnet holder 11 moves away from the facing position only when the magnet holder 11 moves in a specific direction.

In addition, vibration (resonance frequency) that causes the wire columns 6A, 6B, 6C, and 6D to resonate from the outside of the lens driving device 1 while one or both of the second electromagnetic actuator 91A and the third electromagnetic actuator 91B are operating. ), The wire pillars 6A, 6B, 6C, and 6D resonate, and the magnet holder 11 including the lens frame 2 moves against the control signal output by the control means, and moves to a predetermined position. Since the position cannot be maintained, in the present invention, the adhesive member 18 is provided in the coil position restricting portions 31A and 31B, and the base member 3 (coil position restricting portions 31 and 31B) and the magnet 15 (15A and 15B) are provided. The pressure-sensitive adhesive member 18 is in close contact.
Due to the nature of the adhesive member, even when resonance does not occur, a force that hinders the drive of the magnet holder 11 acts to hold the position of the magnet holder 11.
At this time, if the distance between the second electromagnetic actuator 91A as the driving means and the adhesive member 18 is increased, a force for rotating the magnet holder 11 around the adhesive member 18 is generated, and the camera shake correction is quickly performed. Can no longer do.
In order to prevent the rotation, the adhesive member 18 may be arranged at the center of the driving means.
In the present invention, the position sensor 16 is arranged at that position.
Therefore, the adhesive members in the present invention are arranged such that two adhesive members are equidistant from the center of the drive circuit on the central axis (on the magnetization boundary line) of the second electromagnetic actuator 91A as the drive member in the drive direction.
Thereby, it becomes possible to prevent rotation at the time of movement of the magnet holder 11.

FIG. 5 shows an embodiment of a camera 100 incorporating the lens driving device 1.
FIG. 6 shows an embodiment of an electronic device 200 in which the lens driving device 1 is built.
The lens driving device 1 is attached to the camera module 100 or the electronic device 200 (a mobile phone, a smartphone, a tablet PC, a notebook PC, etc.). The camera module 100 and the electronic device 200 including the lens driving device 1 include a camera shake correction mechanism that does not resonate even with external vibration, and can obtain high reliability of resonance suppression.

As mentioned above, although embodiment of this invention has been explained in full detail with reference to drawings, the adhesion member 18 used for this invention should just be a member which has damping property other than ultraviolet curable resin and a thermosetting resin. .
Further, the specific configuration is not limited to these embodiments, and any design change or the like within a range not departing from the gist of the present invention is included in the present invention. Each of the above-described embodiments can be combined by utilizing each other's technology unless there is a particular contradiction or problem in the purpose, configuration, or the like.

1: Lens drive device
2: lens frame, 2A: lens mounting opening, 2B: upper end mounting portion, 2C: lower end mounting portion, 2D: side surface, 2D1: coil holding portion,
3: base member, 3A: opening, 3B: side surface, 3C: back surface, 3E: coil holding part,
31A, 31B: Coil position restricting portion, 3F: Position sensor holding portion, 3G: Insertion hole,
4: Support part,
5: 1st elastic support member, 5A, 5B: Upper leaf | plate spring, 5A1, 5B1: Lens frame attaching part,
5A2, 5A3, 5B2, 5B3: Magnet holder mounting part,
5A4, 5A5, 5B4, 5B5: wire pillar mounting portion,
5A6, 5B6: elastic deformation part,
5C: Lower leaf spring, 5C1: Lens frame mounting portion, 5C2: Magnet holder mounting portion,
5C3: elastic deformation part,
6: 2nd elastic support member, 6A, 6B, 6C, 6D: Wire pillar,
7: Driving means,
11: Magnet holder 11A: Upper edge, 11B: Lower edge,
12A, 12B, 12C, 12D: plate yoke,
13: 1st coil, 14 (14A, 14B, 14C, 14D): 2nd coil,
15 (15A, 15B, 15C, 15D): magnet,
16: Position sensor,
17: Cover member, 17A: Opening,
18: Adhesive member,
19, 19A, 19B: Adhesive member pool,
21: Filter frame 22: Lens barrel,
Oa: optical axis,
F1: a first direction for driving the lens frame 2,
F2: second direction for driving the lens frame 2,
90: first electromagnetic actuator,
91A: second electromagnetic actuator,
91B: Third electromagnetic actuator,
100: Camera 200: Electronic device

Claims (8)

A lens frame, a base member, and a support portion that supports the lens frame so as to be movable in a direction intersecting the optical axis with respect to the base member, and driving the lens frame in a direction intersecting the optical axis. Provided with driving means,
The driving means includes a magnetic circuit using at least a pair of magnets and a driving coil, and a position sensor for detecting the positions of the adhesive member and the lens frame is provided on the magnet in the air core portion of the coil. A lens driving device having a camera shake correction function, wherein the lens driving device is disposed so as to face each other.   2. The lens driving device according to claim 1, wherein the driving means is a magnetic circuit including four sets of magnets and a driving coil. The driving means includes a coil fixed to the base member and a magnet fixed to the lens frame,
The lens driving device according to claim 1, wherein the adhesive member and the position sensor are fixed to a base member. The coil has a major axis and a minor axis, and the center of the magnet and the center of the position sensor are substantially coincident with the center where the major axis and the minor axis of the coil intersect,
4. The lens driving device according to claim 1, wherein the adhesive member is disposed at two positions with the position sensor sandwiched in the long axis direction of the driving coil. 5. The magnetized boundary line of the magnet and the long axis direction of the coil coincide,
The center position of the two adhesive members is on the magnetization boundary line.
Or a lens driving device according to any one of 4 to 4; The lens frame is supported so as to be movable in an optical axis direction and a direction intersecting the optical axis, and the driving means includes driving means for driving the lens frame in an optical axis direction and a direction orthogonal to the optical axis, respectively. The lens driving device according to claim 1, wherein the lens driving device is provided.   A camera comprising the lens driving device according to claim 1. An electronic apparatus comprising the lens driving device according to claim 1.

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