JP5499320B2 - Lens drive device - Google Patents

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 barrel that holds a lens and has a friction member on its side surface, a base that includes a guide portion that supports the lens barrel so as to be movable in the optical axis direction, and a friction member that contacts the friction member. And a piezoelectric actuator that applies a driving force in the optical axis direction to the lens barrel, and a pressing member that presses the piezoelectric actuator toward the lens barrel so as to maintain a contact state between the friction target member and the friction member. Has been.

JP 2008-40076 A

  In the conventional lens driving device described above, at least the piezoelectric actuator, the two shafts, and the friction member are always in contact with the lens holder. Thus, when the number of friction points of the lens holder increases, there is a problem that power consumption during driving increases. In addition, since the number of places that wear due to friction increases, it is difficult to extend the life of the apparatus.

  The present invention has been made in order to solve the above-described problems, and provides a lens driving device capable of reducing power consumption during driving and extending the life of the device by reducing the number of friction points of the lens holder. The purpose is to provide.

  In order to solve the above problems, a lens driving device according to the present invention has a lens holder having a through-hole capable of holding a lens, and the lens holder can be moved in the optical axis direction of the lens and can be rotated around the axis. A first shaft to be supported, a second shaft disposed substantially parallel to the first shaft at a position facing the first shaft across the lens holder, and disposed in contact with a side surface of the lens holder; A piezoelectric actuator that moves the lens holder along the optical axis direction; and an opposing member that is provided on a side surface of the lens holder so as to oppose the second shaft, and is provided between the second shaft and the opposing member. Is characterized in that a magnetic force that rotates the lens holder toward the piezoelectric actuator is acting.

  In this lens driving device, the lens holder is supported by the first shaft so as to be movable in the direction of the optical axis of the lens and to be rotatable about the axis, and the lens holder is piezoelectric between the second shaft and the opposing member. The contact state between the lens holder and the piezoelectric actuator is maintained by applying a magnetic force that rotates toward the actuator side. According to such a configuration, since only the first shaft and the piezoelectric actuator are in contact with the lens holder, the number of friction points of the lens holder can be reduced as compared with the conventional configuration. Therefore, it is possible to reduce power consumption when driving the lens holder. In addition, since the number of parts that wear due to friction is reduced, the life of the apparatus can be extended.

  In addition, a protruding portion that protrudes opposite to the second shaft is formed on the side surface of the lens holder, and the opposing member is provided on the opposite side of the protruding portion from the second shaft. preferable. If it carries out like this, it will become possible to attach an opposing member with respect to a lens holder easily. Moreover, it is possible to prevent the magnetic force acting on the lens holder from becoming excessive because a certain distance is generated between the facing member and the second shaft.

  In addition, it is preferable that the projecting portion and the second shaft are separated from each other in a state where the side surface of the lens holder and the piezoelectric actuator are in contact with each other. Thereby, an increase in the number of friction points of the lens holder can be avoided.

  The second shaft is preferably made of a magnetic material, and the opposing member is preferably made of a magnet. Thereby, the magnetic force which rotates a lens holder toward the piezoelectric actuator side can be made to act suitably.

  In addition, it further includes a base portion provided with a plurality of columns disposed around the first shaft and the second shaft, and the piezoelectric actuator is fixed to a rigid member spanned between the columns, It is preferable that the lens holder is in contact with the side surface of the lens holder. In this configuration, the piezoelectric actuator that receives the pressure from the lens holder is supported by the rigid member, so that the contact state between the piezoelectric actuator and the side surface of the lens holder is more reliably maintained.

  In addition, it further includes a base portion provided with a plurality of support columns arranged around the first shaft and the second shaft, and the piezoelectric actuator is fixed to an elastic member spanned between the support columns, It is preferable that the lens holder is in contact with the side surface of the lens holder. In this configuration, since the piezoelectric actuator that receives pressure from the lens holder is supported by the elastic member, the elastic member undergoes a certain deformation, and a reaction force in the direction toward the lens holder acts on the piezoelectric actuator. Thereby, the contact state between the piezoelectric actuator and the side surface of the lens holder is more reliably maintained.

  According to the present invention, by reducing the number of friction points of the lens holder, it is possible to reduce power consumption during driving and extend the life of the apparatus.

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 front view of the piezoelectric actuator unit in the lens drive device shown in FIG.

  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 that drives a camera lens mounted on, for example, a cellular phone, and includes a base portion 2, a cover portion 3, a lens holder 4, and a piezoelectric actuator unit 5A. 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, a first shaft 11 and a second shaft 12 made of a magnetic material are erected on one surface side of the base portion 2 so as to correspond to one of the diagonal corners. ing. 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 projecting outward is formed on the side surface of the lens holder 4, and the first projecting portion 16 is formed on the first shaft 11. Corresponding insertion holes 16a are formed. 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 (opposing member) 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 </ b> A includes a piezoelectric actuator 21, a plate member 22, and a flexible printed board 26. The piezoelectric actuator unit 5 </ b> A is not in close proximity to a support column 13 (hereinafter referred to as “support column 13 </ b> A”) that is disposed in proximity to the first shaft 11, and neither the first shaft 11 nor 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 the other surface side is a position where expansion and contraction in the thickness direction of the piezoelectric elements does not occur ( The external electrode 23A, the external electrode 23B, and the ground electrode 24 are provided corresponding to the node point.

  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 a rectangular shape, for example, and are spaced apart from each other so as to correspond to the central node point. 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 22 is formed in a substantially rectangular shape having a thickness of about 0.2 mm to 0.3 mm by a rigid member such as stainless steel, and has a function as a fixing member for fixing the piezoelectric actuator 21. Both end portions of the plate member 22 are fixed to the support column 13A and the support column 13B, for example, by adhesion, whereby the plate member 22 is bridged between the support column 13A and the support column 13B. Further, as shown in FIG. 5, a rectangular opening 22a corresponding to the dimension of the piezoelectric actuator 21 is provided at a substantially central portion of the plate member 22, and a support 13A and a support are provided at the center of the opening 22a. A belt-like support portion 22b extending in the direction connecting 13B is formed. The width of the support portion 22b is, for example, about 0.2 mm to 0.3 mm.

  The flexible printed circuit board 26 includes a wiring portion 26a connected to the external electrode 23A, the external electrode 23B, and the ground electrode 24 of the piezoelectric actuator 21 by solder, and an external terminal 26b extending from the wiring portion 26a. The wiring portion 26a is fitted into the opening 22a of the plate member 22 so as to be substantially flush with the inner surface of the plate member 22, and is fixed to the support portion 22b by, for example, adhesion. The external terminal 26 b is drawn out through an opening 27 between the base portion 2 and the cover portion 3.

  In the piezoelectric actuator unit 5 </ b> A having the above configuration, the piezoelectric actuator 21 is fixed to the plate member 22 via the flexible printed board 26 with the bumps 21 a in contact with the side surfaces of the lens holder 4. Accordingly, when a predetermined voltage is applied to the piezoelectric actuator 21, the bump 21a vibrates in the optical axis direction due to expansion and contraction of the piezoelectric element, and the lens holder 4 moves by a predetermined distance along the optical axis direction. ing.

  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 22 by the side surface of the lens holder 4, but the piezoelectric actuator 21 is supported by the plate member 22 formed of a rigid member. The contact state between the bump 21a and the side surface of the lens holder 4 is maintained.

  In addition, in the opening part 22a of the plate member 22, it is preferable that the position of the center node point N1 of the piezoelectric actuator 21 and the position of the support part 22b correspond. In this way, while the piezoelectric actuator 21 is firmly supported by the plate member 22 at a position where the expansion and contraction does not occur, the movement of the piezoelectric actuator 21 can be prevented from being inhibited by the opening 22a being positioned at the portion where the expansion and contraction occurs. .

  Moreover, when forming the lens holder 4 with resin, it is preferable to contain carbon fiber as a filler in the resin. In this case, attenuation of vibration of the bump 21a is suppressed, and the movement efficiency of the lens holder 4 can be sufficiently ensured. In addition to reducing the weight of the lens holder 4 and improving the wear resistance, the lens holder 4 can be prevented from adhering to dust by providing conductivity.

  As described above, in the lens driving device 1A, the lens holder 4 is supported by the first shaft 11 so as to be movable in the optical axis direction of the lens and to be rotatable about the axis, and is made of a magnetic material. A contact state between the lens holder 4 and the piezoelectric actuator 21 is maintained by applying a magnetic force that rotates the lens holder 4 toward the piezoelectric actuator 21 between the shaft 12 and the magnet 18. According to such a configuration, only the first shaft 11 and the piezoelectric actuator 21 are in contact with the lens holder 4, and the number of friction points of the lens holder 4 can be reduced as compared with the conventional configuration. Therefore, the power consumption when driving the lens holder 4 can be reduced. In addition, since the number of parts that wear due to friction is reduced, the life of the apparatus can be extended.

  In the lens driving device 1 </ b> A, a second projecting portion 17 that projects to face the second shaft 12 is formed on the side surface of the lens holder 4, and the magnet 18 is configured to be a second projecting portion. 17 is provided on the side opposite to the second shaft 12. With such a configuration, the magnet 18 can be easily attached to the lens holder 4. Further, since the second overhanging portion 17 is interposed, a constant interval is generated between the magnet 18 and the second shaft 12, so that it is possible to prevent an excessive magnetic force from acting on the lens holder 4. Since the second overhanging portion 17 is separated from the second shaft 12 in a state where the side surface of the lens holder 4 and the piezoelectric actuator 21 are in contact with each other, the number of friction points of the lens holder 4 may increase. Absent.

  Further, in the lens driving device 1A, a base portion 2 provided with a plurality of support columns 13 arranged around the first shaft 11 and the second shaft 12 is provided, and the piezoelectric actuator 21 is provided between the support columns 13A and 13B. In contact with the side surface of the lens holder 4, the plate member 22 is fixed to the plate member 22. The plate member 22 is formed of a rigid member such as stainless steel. As described above, the piezoelectric actuator 21 that receives the pressure from the lens holder 4 is supported by the rigid member, so that the contact state between the piezoelectric actuator 21 and the side surface of the lens holder 4 is more reliably maintained.

[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. FIG. 10 is a plan view of FIG. 9, and FIG. 11 is a front view of the piezoelectric actuator unit in the lens driving device shown in FIG.

  As shown in FIGS. 7 to 11, in the lens driving device 1B according to the second embodiment, the flexible printed circuit board 26 is not provided in the piezoelectric actuator unit 5B, and the configuration of the plate member 30 is the same as in the first embodiment. It is greatly different from the plate member 22. In other words, in the lens driving device 1B, the plate member 30 is formed of an elastic member such as a leaf spring, for example, and functions as a fixing member for fixing the piezoelectric actuator 21 as well as the external electrodes 23A and 23B of the piezoelectric actuator 21 and the ground. It has a function as a wiring member connected to the electrode 24 and a function as a pressing member that presses the piezoelectric actuator 21 toward the side surface of the lens holder 4.

  More specifically, as shown in FIG. 11, the plate member 30 has a first wiring 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 (the direction of arrow A in FIG. 10) is always applied.

  For this reason, the piezoelectric actuator 21 is pressed toward the plate member 22 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 32f, 32f, the connecting portion 33c of the third wiring 33, and the connecting portion 34c of the fourth wiring 34 are elastically deformed, thereby causing a reaction in the direction toward the lens holder 4 (the direction of arrow B in FIG. 10). You will receive power. Thereby, the contact state between the bump 21a of the piezoelectric actuator 21 and the side surface of the lens holder 4 is maintained.

  As shown in FIG. 11, 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.

  Further, 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 34 g of the frame 34 a of the wiring 34 is drawn out to the bottom surface side of the base 2 through an insertion hole 2 a (see FIG. 8) provided in the base 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.

  Also in such a lens driving device 1B, the lens holder 4 is supported by the first shaft 11 so as to be movable in the optical axis direction of the lens and to be rotatable about the axis, and the second shaft 12 made of a magnetic material. By applying a magnetic force for rotating the lens holder 4 toward the piezoelectric actuator 21 between the magnet 18 and the magnet 18, the contact state between the lens holder 4 and the piezoelectric actuator 21 is maintained. According to such a configuration, only the first shaft 11 and the piezoelectric actuator 21 are in contact with the lens holder 4, and the number of friction points of the lens holder 4 can be reduced as compared with the conventional configuration. Therefore, the power consumption when driving the lens holder 4 can be reduced. In addition, since the number of parts that wear due to friction is reduced, the life of the apparatus can be extended.

  Further, in the lens driving device 1B, a second projecting portion 17 that projects to face the second shaft 12 is formed on the side surface of the lens holder 4, and the magnet 18 includes the second projecting portion. 17 is provided on the side opposite to the second shaft 12. With such a configuration, the magnet 18 can be easily attached to the lens holder 4. Further, since the second overhanging portion 17 is interposed, a constant interval is generated between the magnet 18 and the second shaft 12, so that it is possible to prevent an excessive magnetic force from acting on the lens holder 4. Since the second overhanging portion 17 is separated from the second shaft 12 in a state where the side surface of the lens holder 4 and the piezoelectric actuator 21 are in contact with each other, the number of friction points of the lens holder 4 may increase. Absent.

  Further, in the lens driving device 1B, a base portion 2 provided with a plurality of support columns 13 arranged around the first shaft 11 and the second shaft 12 is provided, and the piezoelectric actuator 21 is provided between the support columns 13A and 13B. In contact with the side surface of the lens holder 4, the plate member 22 is fixed to the plate member 22. The plate member 22 is formed of an elastic member such as a leaf spring. According to this configuration, since the piezoelectric actuator 21 that receives the pressure from the lens holder 4 is supported by the elastic member, a certain deformation occurs in the elastic member, and the reaction force in the direction toward the lens holder 4 is applied to the piezoelectric actuator 21. Works. Thereby, the contact state between the piezoelectric actuator 21 and the side surface of the lens holder 4 is more reliably maintained.

  DESCRIPTION OF SYMBOLS 1A, 1B ... Lens drive device, 2 ... Base part, 4 ... Lens holder, 4a ... Through-hole, 11 ... 1st shaft, 12 ... 2nd shaft, 13 ... Support | pillar, 17 ... 2nd overhang | projection part ( Overhang part), 18 ... Magnet (opposing member), 21 ... Piezoelectric actuator, 22, 30 ... Plate member (rigid member, elastic member).

Claims (4)

A lens holder having a through-hole capable of holding a lens;
A first shaft that supports the lens holder so as to be movable in the optical axis direction of the lens and to be rotatable about the axis;
A second shaft disposed substantially parallel to the first shaft at a position facing the first shaft across the lens holder;
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;
An opposing member provided on a side surface of the lens holder so as to face the second shaft,
Between the second shaft and the opposing member, there is a magnetic force that rotates the lens holder toward the piezoelectric actuator side ,
On the side surface of the lens holder, an overhanging portion that protrudes opposite to the second shaft is formed,
The opposing member is provided on the opposite side to the second shaft in the overhanging portion,
The lens driving device , wherein the projecting portion and the second shaft are separated from each other in a state in which the side surface of the lens holder and the piezoelectric actuator are in contact with each other. Said second shaft is formed by a magnetic body, the opposing member is a lens driving device according to claim 1, characterized in that it is formed by the magnet. A base portion provided with a plurality of columns disposed around the first shaft and the second shaft;
The piezoelectric actuator is in a state of being fixed to the rigid member passed bridged between the posts, the lens driving device according to claim 1 or 2, wherein the abutting on the side surface of the lens holder. A base portion provided with a plurality of columns disposed around the first shaft and the second shaft;
The piezoelectric actuator is in a state of being fixed to bridged an elastic member between the posts, the lens driving device according to claim 1 or 2, wherein the abutting on the side surface of the lens holder.

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