JP2011133801A - Lens drive device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens drive device achieving compactness and cost reduction by suppressing increase of the number of part items around a piezoelectric actuator. <P>SOLUTION: In the lens drive device 1A, connection parts 31f, 32f, 33c, 34c are elastically deformed while one side of the piezoelectric actuator 21 abuts against the side face of a lens holder 4, and thereby at least the other side face of the piezoelectric actuator 21 is pressed outside of frame parts 31a, 31b, 32a, 33a, 34a along the normal line of a plate member 30. Thus, a reaction force in the direction toward the lens holder 4 is applied to the piezoelectric actuator 21, and the abutting state between the piezoelectric actuator 21 and the side face of the lens holder 4 is maintained. Since a flexible printed circuit board as in the past is no more necessary, increase of the number of part items around the piezoelectric actuator 21 is suppressed, and compactness and cost reduction of the device is achieved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a lens driving device that drives a camera lens mounted on, for example, a mobile phone.

  As a technology in this type of field, for example, there is a lens driving device described in Patent Document 1. This conventional lens driving device includes a lens holder that holds a lens and has a friction member on a side surface, a base that includes a guide unit that supports the lens holder so as to be movable in the optical axis direction, and a friction member that contacts the friction member. A piezoelectric actuator that applies a driving force in the optical axis direction to the lens holder, and a pressing member that presses the piezoelectric actuator toward the lens holder so as to maintain a contact state between the friction target member and the friction member. Has been.

  For example, the ultrasonic transducer described in Patent Document 2 discloses a configuration of an external terminal connected to a piezoelectric actuator. In this conventional ultrasonic transducer, a flexible printed board having a substrate electrode corresponding to the electrode of the piezoelectric actuator and a grounding electrode is integrally fastened to the piezoelectric actuator by pressure contact.

JP 2008-40076 A Japanese Patent Laid-Open No. 7-115783

  However, when the flexible printed circuit board used in Patent Document 2 described above is applied to the piezoelectric actuator of the lens driving device disclosed in Patent Document 1, the number of parts around the piezoelectric actuator increases. Since the increase in the number of parts around the piezoelectric actuator may hinder downsizing and cost reduction of the apparatus, it is desirable to suppress it as much as possible.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lens driving device that can be reduced in size and cost by suppressing an increase in the number of parts around a piezoelectric actuator. And

  In order to solve the above problems, a lens driving device according to the present invention includes a lens holder having a through-hole capable of holding a lens, a shaft that supports the lens holder so as to be movable in the optical axis direction of the lens, and a shaft around the shaft. A base portion provided with a plurality of disposed support columns, a piezoelectric actuator disposed in contact with the side surface of the lens holder, and moving the lens holder along the optical axis direction; A substantially plate-like pressing member that presses against the side surface, and the piezoelectric actuator has a plurality of piezoelectric elements that expand and contract in accordance with an applied voltage value. The external electrode and the ground electrode are formed corresponding to the node point where the expansion and contraction of the electrode does not occur, and the pressing member is arranged to be connected to the external electrode and the ground electrode, respectively. And a connecting portion that connects the wiring portion and the frame portion. When the one surface side of the piezoelectric actuator is in contact with the side surface of the lens holder, the connecting portion is By elastically deforming, at least the other surface side of the piezoelectric actuator is pushed out of the frame portion along the normal direction of the pressing member.

  In this lens driving device, in a state where one surface side of the piezoelectric actuator is in contact with the side surface of the lens holder, at least the other surface side of the piezoelectric actuator is moved from the frame portion along the normal direction of the pressing member by elastically deforming the connecting portion. Is also pushed out. Due to the elastic deformation of the connecting portion, a reaction force in the direction toward the lens holder acts on the piezoelectric actuator, so that the contact state between the piezoelectric actuator and the side surface of the lens holder is maintained. The pressing member includes a wiring part connected to the external electrode and the ground electrode, a frame part fixed to the support column, and a connecting part that connects the wiring part and the frame part. Accordingly, the pressing member also has a function as an external terminal of the piezoelectric actuator, and a conventional flexible printed board is not necessary, so that an increase in the number of parts around the piezoelectric actuator can be suppressed. Thereby, size reduction and cost reduction of an apparatus are achieved.

  Moreover, it is preferable that the base part is provided with an insertion hole through which the frame part of the pressing member passes, and an end part of the frame part is drawn out to the outside of the base part through the insertion hole. Thereby, since the structure around the piezoelectric actuator is further simplified, the apparatus can be further miniaturized.

  Moreover, it is preferable that the connection part is bent several times between the wiring part and the frame part. In this way, the length of the connecting portion is ensured, and a predetermined spring constant for the piezoelectric actuator to press the side surface of the lens holder is obtained.

  Moreover, it is preferable that the pressing member is spanned between adjacent struts in the base portion. According to such a configuration, since the piezoelectric actuator can be disposed close to the side surface of the lens holder by utilizing the empty space between the support columns, the device can be further downsized.

  According to the present invention, it is possible to reduce the size and cost by suppressing an increase in the number of parts around the piezoelectric actuator.

1 is a perspective view showing a lens driving device according to a first embodiment of the present invention. It is a disassembled perspective view of the lens drive device shown in FIG. It is a perspective view which shows the lens drive device shown in FIG. 1 in the state which removed the cover part. FIG. 4 is a plan view of FIG. 3. It is a front view of the piezoelectric actuator unit in the lens drive device shown in FIG. It is a figure which shows the mode at the time of the drive of a piezoelectric actuator. It is a perspective view which shows the lens drive device which concerns on 2nd Embodiment of this invention. FIG. 8 is an exploded perspective view of the lens driving device shown in FIG. 7. It is a perspective view which shows the lens drive device shown in FIG. 7 in the state which removed the cover part. FIG. 10 is a plan view of FIG. 9. It is a principal part enlarged view which shows the 2nd overhang | projection part which concerns on a modification.

  Hereinafter, a preferred embodiment of a lens driving device according to the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a perspective view showing a lens driving device according to a first embodiment of the present invention. 2 is an exploded perspective view thereof, and FIG. 3 is a perspective view of the lens driving device shown in FIG. 1 with the cover portion removed. FIG. 4 is a plan view of FIG. A lens driving device 1A shown in FIGS. 1 to 4 is a device for driving a camera lens mounted on, for example, a mobile phone, and includes a base portion 2, a cover portion 3, a lens holder 4, and a piezoelectric actuator unit 5. And is configured.

  The base portion 2 is formed of, for example, a liquid crystal polymer containing a glass fiber or an inorganic filler, and has a flat and substantially rectangular parallelepiped shape. As shown in FIGS. 2 and 3, on one surface side of the base portion 2, a first shaft 11 having a true circular cross section made of a magnetic material and corresponding to the corner portions 2b, 2b opposed on one diagonal line and Two shafts 12 are erected. In addition, on one surface side of the base portion 2, four support columns 13 are erected around the first shaft 11 and the second shaft 12 so as to correspond to the four corners.

  The cover part 3 is formed of, for example, SPCC (cold rolled steel) and has a hollow, substantially rectangular parallelepiped shape with one surface opened. As shown in FIGS. 1 and 2, a circular opening 3 a that exposes a lens (not shown) attached to the lens holder 4 is formed in the central portion of the surface of the cover portion 3. In addition, circular openings 3b are formed around the openings 3a corresponding to the positions of the first shaft 11, the second shaft 12, and the support columns 13, respectively. As shown in FIG. 1, the cover portion 3 is in a state where the tip portion 11 a of the first shaft 11, the tip portion 12 a of the second shaft 12, and the tip portion 13 a of the column 13 are passed through the opening 3 b, respectively. For example, it is fixed to the base portion 2 by heat caulking.

  The lens holder 4 is formed of, for example, a liquid crystal polymer including a carbon fiber, and has a cylindrical shape with a substantially octagonal cross section. As shown in FIGS. 2 and 3, a through hole 4 a that can hold the lens is formed in the center portion of the lens holder 4. Further, as shown in FIG. 4, a first projecting portion 16 is formed on the side surface of the lens holder 4 so as to project outward toward the same extent as the height of the lens holder 4. Is formed with an insertion hole 16 a corresponding to the first shaft 11. The lens holder 4 is movable in the axial direction of the first shaft 11 (the optical axis direction of the lens) by passing the first shaft 11 through the insertion hole 16a of the first overhanging portion 16, and the first holder 11 The shaft 11 is supported so as to be rotatable.

  Further, on the side surface of the lens holder 4, a plate-like second projecting portion 17 is formed at a position facing the first projecting portion 16. The second overhanging portion 17 is disposed close to the second shaft 12 in a state where the lens holder 4 is supported by the first shaft 11, and the second shaft in the second overhanging portion 17. A rectangular magnet 18 is fixed to the surface opposite to the surface 12.

  Accordingly, the lens holder 4 is rotated in the direction in which the second overhanging portion 17 is attracted to the second shaft 12 by the magnetic force generated between the magnet 18 and the second shaft 12 (the arrow in FIG. 4). A biasing force in the A direction) is always applied. The rotation of the lens holder 4 stops at a position where the side surface of the lens holder 4 abuts against the bump 21 a of the piezoelectric actuator 21, and in this state, between the second overhanging portion 17 and the second shaft 12. Are formed at regular intervals.

  In the lens driving device 1A, the second shaft 12 and the magnet 18 are disposed at a position facing the first shaft 11 with the lens holder 4 interposed therebetween. Therefore, the first shaft 11 and the first shaft 11, which is the rotation center of the lens holder 4, and the distance between the bump 21 a, which is an action point at which the piezoelectric actuator 21 presses the side surface of the lens holder 4, Since a sufficient distance from the second shaft 12 can be secured, the magnetic force of the magnet 18 can be made relatively small.

  On the other hand, as shown in FIG. 5, the piezoelectric actuator unit 5 includes a piezoelectric actuator 21 and a plate member (pressing member) 30. The piezoelectric actuator unit 5 is not in close proximity to any one of the support 13 (hereinafter referred to as “support 13 </ b> A”) disposed close to the first shaft 11 and the first shaft 11 and the second shaft 12. Of the two struts 13, the struts 13 are disposed between the struts 13 (hereinafter referred to as “struts 13 </ b> B”) disposed on the tip end side in the direction of arrow A as viewed from the second overhanging portion 17 side (FIG. 3). reference).

  The piezoelectric actuator 21 has a plurality of piezoelectric elements that expand and contract in accordance with the applied voltage value. A plurality of, for example, semi-cylindrical bumps 21a are provided on one surface side of the piezoelectric actuator 21 along the arrangement direction of the piezoelectric elements, and on the other surface side, a position (node point) where the piezoelectric element does not expand and contract. Correspondingly, an external electrode 23A, an external electrode 23B, and a ground electrode 24 are provided.

  The piezoelectric actuator 21 is expanded and contracted during driving by superimposing a longitudinal vibration mode in which the piezoelectric elements vibrate in the arrangement direction and a bending vibration mode in which the piezoelectric element vibrates in the thickness direction. FIG. 6 is a diagram showing a state in which the piezoelectric actuator 21 is driven. When a predetermined voltage is applied between the external electrodes 23A and 23B and the ground electrode 24, FIG. 6 (a) and FIG. As shown in b), the bump 21a of the piezoelectric actuator 21 drives the lens holder 4 along the optical axis direction.

  In the example shown in the figure, the boundary portion of the piezoelectric element and the position that is about 1/6 L from the end of the piezoelectric actuator when the length in the arrangement (optical axis) direction of the piezoelectric actuator 21 is L, There are three node points N1, N2, and N3. The node point N1 is not displaced in the direction in which the piezoelectric elements are arranged or in the thickness direction, and the node points N2, N3 are displaced in the direction in which the piezoelectric elements are arranged, but are not displaced in the thickness direction. ing.

  The external electrode 23A and the external electrode 23B have, for example, a rectangular shape and are provided apart from each other so as to correspond to the central node point N1. The ground electrode 24 is formed in a strip shape from the node point N2 on one side of the central node point N1 to the node point N3 on the other side of the central node point N1.

  The plate member 30 is formed in an approximately rectangular shape by an elastic member such as a leaf spring, for example, and functions as a fixing member that fixes the piezoelectric actuator 21 and a pressing member that presses the piezoelectric actuator 21 toward the side surface of the lens holder 4. And a function as an external terminal of the piezoelectric actuator 21. More specifically, as shown in FIG. 5, the plate member 30 includes a first wire 31 connected to one end of the ground electrode 24 of the piezoelectric actuator 21 and a first wire 31 connected to the other end of the ground electrode 24. The second wiring 32, the third wiring 33 connected to the external electrode 23A, and the fourth wiring 34 connected to the external electrode 23B are formed in a substantially rectangular plate shape as a whole.

  The first wiring 31 extends between the columns 13A and 13B at positions closer to the distal ends of the columns 13A and 13B than the piezoelectric actuator 21 and the frame portions 31a and 31a extending along the columns 13A and 13B. It has a frame part 31 b and a wiring part 31 c that connects the frame part 31 b and one end of the ground electrode 24. The wiring portion 31c includes a connection portion 31d fixed to one end of the ground electrode 24, end portions 31e and 31e connected to the frame portion 31b on both sides of the piezoelectric actuator 21, and end portions 31e and 31e from both ends of the connection portion 31d. It has the connection parts 31f and 31f extended to 31e.

  The second wiring 32 includes a frame portion 32a extending between the support column 13A and the support column 13B at a position closer to the base ends of the support column 13A and the support column 13B than the piezoelectric actuator 21, and the other end of the frame portion 32a and the ground electrode 24. And a frame part 32c extending from the approximate center of the frame part 32a to the base part 2 side. The wiring portion 32b includes a connection portion 32d fixed to the other end of the ground electrode 24, end portions 32e and 32e connected to the frame portion 32a on both sides of the piezoelectric actuator 21, and end portions 32e and 32e from both ends of the connection portion 32d. It has the connection parts 32f and 32f extended to 32e. The wiring part 32 b of the second wiring 32 is connected to the wiring part 31 c of the first wiring 31 by a connecting part 35 extending along the ground electrode 24.

  The third wiring 33 is connected to the frame portion 33a extending along the column 13B on the inner side of the frame portion 31a of the first wiring 31, the connection portion 33b fixed to the external electrode 23A, and the frame portion 33a. It has the connection part 33c which connects the part 33b. The fourth wiring 34 includes a frame portion 34a extending along the support column 13A inside the frame portion 31a of the first wiring 32, a connection portion 34b fixed to the external electrode 23B, a frame portion 34a, and a connection portion 34b. And a connecting portion 34c that connects the two.

  The plate member 30 having such a configuration has the bumps 21a of the piezoelectric actuator 21 on the side surface of the lens holder 4 by the frame portions 31a and 31a of the first wiring 31 being bonded to the inside of the support pillars 13A and 13B. In the abutting state, it is bridged between the column A and the column B and fixed. At this time, as described above, the lens holder 4 is rotated in the direction in which the second overhanging portion 17 is attracted to the second shaft 12 by the magnetic force generated between the magnet 18 and the second shaft 12. The urging force in the direction (direction of arrow A in FIG. 4) is always applied.

  For this reason, the piezoelectric actuator 21 is pressed toward the plate member 30 by the side surface of the lens holder 4, but the connection portions 31 f and 31 f of the first wiring 31 and the second wiring 32 formed of an elastic member are connected. The portions 32 f and 32 f, the connecting portion 33 c of the third wiring 33, and the connecting portion 34 c of the fourth wiring 34 are elastically deformed, and at least the other surface side of the piezoelectric actuator 21 is framed along the normal direction of the plate member 30. The parts 31a, 31b, 32a, 33a, and 34a are pushed outward. As a result, a reaction force in the direction toward the lens holder 4 (in the direction of arrow B in FIG. 4) acts on the piezoelectric actuator 21, and the contact state between the bump 21a of the piezoelectric actuator 21 and the side surface of the lens holder 4 is maintained. Is done.

  As shown in FIG. 5, the connecting portions 31f and 31f of the first wiring 31 and the connecting portions 32f and 32f of the second wiring 32 are bent at a substantially right angle a plurality of times. Accordingly, the lengths of the connecting portions 31f and 31f of the first wiring 31 and the connecting portions 32f and 32f of the second wiring 32 are ensured, and the piezoelectric actuator 21 has a predetermined length for pressing the side surface of the lens holder 4. The spring constant is obtained.

  Further, at the node point N1 of the piezoelectric actuator 21, for example, solder is used to fix the external electrode 23A and the connecting portion 33b, fix the external electrode 23B and the connecting portion 34b, and fix the ground electrode 24 and the connecting portion 35. Used. Then, at the node points N2 and N3 of the piezoelectric actuator 21, for example, a silicone adhesive is used for fixing the element body portion of the piezoelectric element and the connection portion 31d and fixing the element body portion of the piezoelectric element and the connection portion 32d. It is done.

  As a result, the piezoelectric actuator 21 and the plate member 30 are firmly fixed at the node point N1 that is not displaced in the arrangement direction or thickness direction of the piezoelectric elements, and is displaced in the arrangement direction of the piezoelectric elements, but in the thickness direction. Since the piezoelectric actuator 21 and the plate member 30 are flexibly fixed at the node points N2 and N3 that are not displaced, the posture of the piezoelectric actuator 21 with respect to the plate member 30 can be stabilized.

  On the other hand, the end portions 31g and 31g of the frame portions 31a and 31a of the first wiring 31, the end portion 32g of the frame portion 32c of the second wiring 32, the end portion 33g of the frame portion 33a of the third wiring 33, and the fourth. An end portion 34 g of the frame portion 34 a of the wiring 34 is drawn out to the bottom surface side of the base portion 2 through an insertion hole 2 a (see FIG. 2) provided in the base portion 2. Each end 31g, 31g, 32g, 33g, 34g functions as an external terminal of the piezoelectric actuator 21.

  These external terminals are preferably formed by connecting portions drawn to the bottom surface side of the base portion 2 to each other, insert-molding together with the base portion 2, and then cutting the connection portion. Further, when the connecting portion is not formed, the end portions 31g, 31g, 32g, 33g, and 34g can be passed through the insertion holes 2a of the base portion 2 as external terminals.

  As described above, in the lens driving device 1 </ b> A, the connecting portions 31 f, 32 f, 33 c, and 34 c are elastically deformed in a state where one surface side of the piezoelectric actuator 21 is in contact with the side surface of the lens holder 4. At least the other surface side is pushed outside the frame portions 31 a, 31 b, 32 a, 33 a, 34 a along the normal direction of the plate member 30. Due to the elastic deformation of the connecting portions 31f, 32f, 33c, and 34c, a reaction force in the direction toward the lens holder 4 acts on the piezoelectric actuator 21, so that the piezoelectric actuator 21 and the side surface of the lens holder 4 are in contact with each other. Is maintained.

  The plate member 30 includes wiring portions 31d, 32d, 33b, 34b connected to the external electrodes 23A, 23B and the ground electrode 24, frame portions 31a, 31a fixed to the support columns 13A, 13B, and wiring. It has the connection parts 31f, 32f, 33c, and 34c which connect the part 31d, 32d, 33b, and 34b and frame part 31a, 31b, 32a, 33a, 34a. Therefore, the plate member 30 also has a function as an external terminal of the piezoelectric actuator 21, and a conventional flexible printed circuit board is not necessary, so that an increase in the number of parts around the piezoelectric actuator 21 can be suppressed. Thereby, size reduction and cost reduction of an apparatus are achieved.

  Further, the base portion 2 is provided with an insertion hole 2a through which the frame portions 31a, 31b, 32c, 33a, and 34a of the plate member 30 pass, and end portions 31g, 31g, and 31g, 31g, and 31a of the frame portions 31a, 31b, 32c, 33a, and 34a, respectively. 32g, 33g, and 34g are drawn out of the base part 2 through the insertion hole 2a. As a result, the configuration around the piezoelectric actuator 21 is further simplified, so that the apparatus can be further miniaturized.

  Further, the plate member 30 is spanned between the adjacent support columns 13A and 13B in the base portion 2. According to such a configuration, the piezoelectric actuator 21 can be disposed close to the side surface of the lens holder 4 by utilizing the empty space between the support columns 13A and 13B, so that the device can be further downsized.

[Second Embodiment]
Subsequently, a second embodiment of the present invention will be described. FIG. 7 is a perspective view showing a lens driving apparatus according to the second embodiment of the present invention. FIG. 8 is an exploded perspective view thereof, and FIG. 9 is a perspective view showing the lens driving device shown in FIG. 7 with the cover portion removed. Further, FIG. 10 is a plan view of FIG.

  As shown in FIGS. 7 to 10, the lens driving device 1 </ b> B according to the second embodiment is different from the first embodiment in the configuration in the vicinity of the second shaft 12, and other configurations are the same as those in the first embodiment. It is the same. More specifically, in the lens driving device 1B, the second projecting outward from the portion near the base portion 2 in the lens holder 4 at a position facing the first projecting portion 16 on the side surface of the lens holder 4. The overhanging portion 47 is formed.

  An insertion hole 47 a corresponding to the second shaft 12 is formed in the second overhang portion 47. The cross-sectional shape of the insertion hole 47a is substantially elliptical. As shown in FIG. 10, the position of the first shaft 11 and the position of the second shaft 12 are approximately the same width as the diameter of the second shaft 12. Extends along the first direction L1. The second shaft 12 is passed through a substantially central portion of the insertion hole 47a, and the peripheral surface of the second shaft 12 is in contact with an inner wall surface that forms the insertion hole 47a. Thereby, the rotation around the first shaft 11 is restricted in the movement of the lens holder 4 permitted by the first shaft 11.

  Also in such a lens driving device 1B, in a state where one surface side of the piezoelectric actuator 21 is in contact with the side surface of the lens holder 4, the connecting portions 31f, 32f, 33c, and 34c are elastically deformed, so that at least other parts of the piezoelectric actuator 21 are obtained. The surface side is pushed out of the frame portions 31 a, 31 b, 32 a, 33 a, and 34 a along the normal direction of the plate member 30. Due to the elastic deformation of the connecting portions 31f, 32f, 33c, and 34c, a reaction force in the direction toward the lens holder 4 along the second direction L2 that intersects the first direction L1 acts on the piezoelectric actuator 21. Therefore, the contact state between the piezoelectric actuator 21 and the side surface of the lens holder 4 is maintained.

  The plate member 30 includes wiring portions 31d, 32d, 33b, 34b connected to the external electrodes 23A, 23B and the ground electrode 24, frame portions 31a, 31a fixed to the support columns 13A, 13B, and wiring. It has the connection parts 31f, 32f, 33c, and 34c which connect the part 31d, 32d, 33b, and 34b and frame part 31a, 31b, 32a, 33a, 34a. Therefore, the plate member 30 also has a function as an external terminal of the piezoelectric actuator 21, and a conventional flexible printed circuit board is not necessary, so that an increase in the number of parts around the piezoelectric actuator 21 can be suppressed. Thereby, size reduction and cost reduction of an apparatus are achieved.

  Further, the base portion 2 is provided with an insertion hole 2a through which the frame portions 31a, 31b, 32c, 33a, and 34a of the plate member 30 pass, and end portions 31g, 31g, and 31g, 31g, and 31a of the frame portions 31a, 31b, 32c, 33a, and 34a, respectively. 32g, 33g, and 34g are drawn out of the base part 2 through the insertion hole 2a. As a result, the configuration around the piezoelectric actuator 21 is further simplified, so that the apparatus can be further miniaturized.

  Further, the plate member 30 is spanned between the adjacent support columns 13A and 13B in the base portion 2. According to such a configuration, the piezoelectric actuator 21 can be disposed close to the side surface of the lens holder 4 by utilizing the empty space between the support columns 13A and 13B, so that the device can be further downsized.

  The present invention is not limited to the above embodiment. For example, in the second embodiment described above, the insertion hole 47a extending along the first direction L1 is provided in the second overhanging portion 47 of the lens holder 4, but instead of the insertion hole 47a, for example in FIG. As shown, a cutout groove 48 b having a cross-sectional shape extending along the first direction L <b> 1 may be provided in the second overhanging portion 48 of the lens holder 4. Even if it is such a form, the effect similar to embodiment mentioned above is acquired.

  DESCRIPTION OF SYMBOLS 1A, 1B ... Lens drive device, 2 ... Base part, 2a ... Insertion hole, 4 ... Lens holder, 4a ... Through-hole, 11 ... 1st shaft, 12 ... 2nd shaft, 13A, 13B ... Column, 21 ... Piezoelectric actuator, 23A, 23B ... external electrode, 24 ... ground electrode, 30 ... plate member (pressing member), 31d, 32d, 33b, 34b ... wiring portion, 31a, 31b, 32a, 32c, 33a, 34a ... frame portion, 31f, 32f, 33c, 34c ... connecting part, end part ... 31g, 31g, 32g, 33g, 34g, N1 to N3 ... node points.

Claims (4)

A lens holder having a through-hole capable of holding a lens;
A base portion provided with a shaft for movably supporting the lens holder in the optical axis direction of the lens, and a plurality of support columns arranged around the shaft;
A piezoelectric actuator that is disposed in contact with a side surface of the lens holder and moves the lens holder along the optical axis direction;
A substantially plate-like pressing member that presses one side of the piezoelectric actuator against the side surface of the lens holder;
The piezoelectric actuator has a plurality of piezoelectric elements that expand and contract in accordance with an applied voltage value,
On the other surface side of the piezoelectric actuator, an external electrode and a ground electrode are formed corresponding to a node point that is a position where expansion and contraction of the piezoelectric element does not occur,
The pressing member is
Wiring portions connected to the external electrode and the ground electrode, respectively.
A frame portion fixed to the column;
A connecting portion that connects the wiring portion and the frame portion;
In a state where one surface side of the piezoelectric actuator is in contact with the side surface of the lens holder, the connecting portion is elastically deformed, so that at least the other surface side of the piezoelectric actuator extends from the frame portion along the normal direction of the pressing member. A lens driving device characterized in that the lens driving device is also pushed outward. The base portion is provided with an insertion hole through which the frame portion of the pressing member passes,
The lens driving device according to claim 1, wherein an end portion of the frame portion is pulled out to the outside of the base portion through the insertion hole.   The lens driving device according to claim 1, wherein the connecting portion is bent a plurality of times between the wiring portion and the frame portion.   The lens driving device according to claim 1, wherein the pressing member is stretched between adjacent struts in the base portion.

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