JP2013109248A - Anti-vibration actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-vibration actuator which can be easily reduced in size.SOLUTION: An anti-vibration actuator (20) includes: a fixing part (22); a movable part (24) to which an image blur prevention lens (26) is attached; movable part support means (46) for supporting the movable part so that it is movable within a plane orthogonal to an optical axis; and driving means for driving the movable part in first and second directions. The driving means includes: driving magnets (52a, 52b); and two sets of driving coils for generating driving forces by magnetic fields of the driving magnets. The first set of driving coils (48a, 48b) for generating the driving force in the first direction are adjacently arranged on the same plane orthogonal to the optical axis, and the second set of driving coils (50a, 50b) for generating the driving force in the second direction are adjacently arranged on the other same plane which is orthogonal to the optical axis. The first and second sets of driving coils are arranged so as to be overlapped with each other in projection in an optical axis direction.

Description

  The present invention relates to an image stabilization actuator, and more particularly to an image stabilization actuator for moving an image stabilization lens.

  Japanese Patent Laid-Open No. 2007-293125 (Patent Document 1) describes an imaging device. This image pickup apparatus includes a camera shake prevention mechanism that drives a lens holder to which an image blur correction lens is attached in a plane perpendicular to the optical axis. This camera shake prevention mechanism includes coils attached to both sides of the image shake correction lens of the lens holder, and magnets disposed so as to face these coils. The lens holder is supported by four linear wires arranged in parallel to the optical axis of the correction lens and symmetrically with respect to the optical axis. Further, a driving force is generated by passing an electric current through the coil, and the lens holder is moved in a plane perpendicular to the optical axis.

JP 2007-293125 A

  However, in the imaging apparatus described in Japanese Patent Application Laid-Open No. 2007-293125, since the coils and magnets for driving the lens holder are arranged on both sides of the correction lens, the drive mechanism for the correction lens can be reduced in size. There is a problem that is difficult. In particular, such a drive mechanism has a problem that it is difficult to incorporate into a thin compact camera in which the optical axis is bent by 90 ° in the middle or a camera built in a mobile phone.

  Accordingly, an object of the present invention is to provide an anti-vibration actuator that can be easily downsized.

  In order to solve the above-described problems, the present invention provides a vibration-proof actuator for moving an image blur prevention lens, and includes a fixed portion fixed to the housing, and a movable unit to which the image blur prevention lens is attached. A movable portion supporting means for movably supporting the movable portion with respect to the fixed portion within a plane perpendicular to the optical axis of the image blur prevention lens, and the movable portion within a plane perpendicular to the optical axis. And a driving means for driving in a first direction and a second direction different from the first direction, and the driving means is for driving attached to either the fixed part or the movable part. Two sets of driving coils that generate a driving force by interaction with a magnet and a magnetic field formed by the driving magnet, which is attached to one of the fixed part and the movable part where the driving magnet is not attached; And the first set of drive coils The driving coils are arranged adjacent to each other on the same plane orthogonal to the optical axis so as to generate the driving force in the first direction, and the second set of driving coils of the driving coils is the second Are arranged adjacent to each other on the same plane orthogonal to the optical axis different from the plane on which the first set of driving coils are arranged so as to generate a driving force in the direction of The coil and the second set of driving coils are arranged so as to overlap in the projection in the optical axis direction.

  In the present invention configured as described above, the movable portion to which the image blur prevention lens is attached is moved relative to the fixed portion within a plane perpendicular to the optical axis of the image blur prevention lens by the movable portion support means. Supported as possible. The driving means drives the movable part in the first direction and the second direction within a plane orthogonal to the optical axis. The driving means includes a driving magnet and two sets of driving coils that generate a driving force by interaction with a magnetic field generated by the driving magnet. The driving coils of each set are arranged adjacent to each other on the same plane orthogonal to the optical axis, and are arranged so as to overlap in the projection in the optical axis direction.

  According to the present invention thus configured, each set of driving coils is disposed adjacent to each other on the same plane orthogonal to the optical axis, and is disposed so as to overlap in the projection in the optical axis direction. Therefore, the drive means can be configured compactly, and the vibration-proof actuator can be reduced in size. This makes it possible to employ the vibration-proof actuator of the present invention for a thin imaging device using an optical system in which the optical axis is bent 90 ° in the middle. In addition, since each set of driving coils is arranged so as to overlap in the projection in the optical axis direction, the driving force in the first direction and the second direction is generated by a single magnetic field by the driving magnet. It becomes possible.

  In the present invention, it is preferable that the movable portion supporting means includes four elastic members extending in the optical axis direction between the fixed portion and the movable portion, and these four elastic members are the first set of driving members. The second direction straight line extending between the coils for use and the first direction straight line extending between the second set of drive coils are arranged at symmetrical positions.

  According to the present invention configured as described above, the four elastic members are arranged at symmetrical positions with respect to the straight line in the first direction and the straight line in the second direction. The force acts in a well-balanced manner, and the generation of moment due to the driving force generated by the first and second sets of driving coils is suppressed. For this reason, the movable part is translated in substantially the first and second directions by the driving force generated by the first and second sets of driving coils.

  In the present invention, preferably, the four elastic members are made of a conductive material, and these four elastic members are used as conductors of a current flowing through two sets of driving coils.

  According to the present invention configured as described above, since the elastic member is used as a conductor for the current flowing through the driving coil, it is not necessary to provide a separate conductor for guiding the current, reducing the number of components and preventing vibration. The assembling property of the actuator can be improved. Further, disturbance due to the movement of the movable part, which is caused by separately providing a conductor for guiding current, can be removed.

In the present invention, preferably, the four elastic members are made of a nonmagnetic material.
According to the present invention configured as above, since the four elastic members are made of a non-magnetic material, each elastic member receives a magnetic force from the driving magnet and becomes a disturbance to the movement of the movable part. Can be prevented.

  In the present invention, preferably, the first set of drive coils is composed of two drive coils having the same shape of a substantially rectangular shape, and the second set of drive coils is two drive coils having the same shape of a substantially rectangular shape. The long side length of the first set of drive coils is approximately twice the short side length of the second set of drive coils. The length of the long side is approximately twice the length of the short side of the first set of driving coils.

  According to the present invention configured as described above, the maximum driving coil can be arranged in the same projected area in the optical axis direction, and a large driving force is generated by the driving coil with a small exclusive area. It becomes possible to make it.

  In the present invention, preferably, the first set of driving coils are supplied with currents in opposite directions so that currents in the same direction flow in adjacent winding portions, and the second set of driving coils. Currents in opposite directions flow so that currents in the same direction flow in adjacent winding portions, and the driving magnets receive currents in the same direction of the first and second sets of driving coils. A magnetic field is formed in the flowing winding part.

  According to the present invention configured as described above, since the magnetic field is formed in the winding portion where the current in the same direction flows by the driving magnet, the driving force can be generated efficiently.

  In the present invention, preferably, two drive magnets are provided so as to face each other in the optical axis direction, and a first set of drive coils and a second set of drive coils are provided between these drive magnets. Has been placed.

  According to the present invention thus configured, the magnetic field acting on the first set of drive coils and the second set of drive coils can be strengthened. Thereby, each drive coil and drive magnet can be configured in a small size, and the vibration-proof actuator can be further downsized.

  According to the present invention, the vibration-proof actuator can be easily downsized.

It is front sectional drawing of the imaging device incorporating the vibration proof actuator by embodiment of this invention. It is side surface sectional drawing of the imaging device incorporating the anti-vibration actuator by embodiment of this invention. It is a perspective view of a vibration proof actuator according to an embodiment of the present invention. It is a disassembled perspective view of the vibration proof actuator by embodiment of this invention. It is a disassembled perspective view of the movable part of the vibration proof actuator by embodiment of this invention. It is sectional drawing of the vibration proof actuator which follows the vi-vi line | wire of FIG. FIG. 7 is a diagram showing the arrangement of each drive coil and drive magnet.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.
First, with reference to FIGS. 1 to 7, an image pickup apparatus incorporating a vibration-proof actuator according to an embodiment of the present invention will be described. FIG. 1 is a front sectional view of an imaging apparatus incorporating a vibration-proof actuator according to an embodiment of the present invention, and FIG. 2 is a side sectional view of the imaging apparatus.

  As shown in FIGS. 1 and 2, an imaging apparatus 1 incorporating a vibration-proof actuator according to an embodiment of the present invention includes a housing 2, a prism 4, a first lens 6 that is an imaging lens, and a second lens 8. The third lens 10, the fourth lens 12, and the fifth lens 14, the shutter unit 16, the image sensor 18, and the vibration isolation actuator 20. In addition, an image stabilization lens 26 is attached to the image stabilization actuator 20. A gyroscope 56 that is a shake detection unit that detects the shake of the imaging apparatus 1 is attached to the housing 2. In FIGS. 1 and 2, the first to fifth lenses and the image blur prevention lens 26 are each shown as one lens, but these lenses are a combination of a plurality of lenses. It may be a lens group.

  The light incident on the first lens 6 is bent by 90 ° by the prism 4, and then along the optical axis A of the image blur prevention lens 26, the second lens 8, the shutter unit 16, the image blur prevention lens 26, The light passes through the third lens 10, the fourth lens 12, and the fifth lens 14 and is focused on the image sensor 18. Further, the second lens 8 and the fourth lens 12 are arranged so as to be movable along the optical axis A, thereby enabling angle of view adjustment and focus adjustment.

  The imaging device 1 detects vibration by the gyro 56 and operates the image stabilization actuator 20 based on the detected vibration to move the image stabilization lens 26 to stabilize the image focused on the image sensor 18. I am letting. In the present embodiment, a piezoelectric vibration gyro is used as the gyro 56.

  Next, with reference to FIG. 3 thru | or FIG. 7, the anti-vibration actuator 20 by embodiment of this invention is demonstrated. FIG. 3 is a perspective view of the vibration-proof actuator according to the embodiment of the present invention. FIG. 4 is an exploded perspective view of the vibration-proof actuator 20. FIG. 5 is an exploded perspective view of the movable part of the vibration-proof actuator 20. FIG. 6 is a cross-sectional view of the vibration isolation actuator 20 along the line vi-vi in FIG. FIG. 7 is a diagram showing the arrangement of each drive coil and drive magnet.

  As shown in FIGS. 3 to 5, the vibration isolation actuator 20 includes a base member 22 fixed to the housing 2 and a movable portion 24 to which an image blur prevention lens 26 is attached. Is configured to be movable with respect to the base member 22 in a plane orthogonal to the optical axis A of the image blur prevention lens 26.

  In addition, an L-shaped cover 28, a flexible substrate 30, four adsorption yokes 44, two drive magnets 52 a and 52 b, and a drive magnet yoke 54 are attached to the base member 22. Further, two Hall elements 32 as position detecting means are attached to the flexible substrate 30. In the present embodiment, the base member 22, the cover 28, and the flexible substrate 30 constitute a fixed portion attached to the housing 2.

  On the other hand, the movable portion 24 includes an image blur prevention lens 26, four back yokes 34, four attracting magnets 36, two position detecting magnets 38a and 38b, and two position detecting yokes 40. The first set of drive coils 48a and 48b and the second set of drive coils 50a and 50b are attached.

  In addition, three support balls 42 are sandwiched between the base member 22 and the movable portion 24. Further, the flexible substrate 30 attached to the base member 22 and the movable portion 24 are connected by four coil springs 46 that are elastic members. These support balls 42 and coil springs 46 function as movable part support means for supporting the movable part 24 movably with respect to the base member 22 in a plane perpendicular to the optical axis A of the image blur prevention lens 26. To do.

  As shown in FIG. 4, the base member 22 is a resin member formed in an approximately L shape. The base member 22 is provided with a circular opening 22 a at a position aligned with the image blur prevention lens 26 attached to the movable portion 24. Around this circular opening 22a, three circular recesses 22b for arranging the support balls 42 are formed. Further, four circular recesses (not shown) for embedding the suction yokes 44 are provided on the back surface side of the base member 22. Further, the base member 22 is provided with two cutout portions 22c for fitting the drive magnet yoke 54 therein.

  The cover 28 is a metal plate that is bent in an approximately L shape. The base 28 is such that one of the bent faces overlaps a part of the base member 22 and the other face faces a part of the base member 22. It is attached to the member 22. A circular opening 28a is provided at a position where the cover 28 is aligned with the image blur prevention lens 26, and a cutout 28b is provided at a position where the drive magnet yoke 54 is attached.

  The flexible substrate 30 is a flexible and elongated substrate, and is attached to the back side of the cover 28. Further, like the cover 28, a circular opening 30a and a cutout 30b are provided. Further, two Hall elements 32 a and 32 b are attached to the back surface side of the flexible substrate 30. Detection signals from the hall elements 32a and 32b are transmitted to a control unit (not shown) by a substrate pattern (not shown) provided on the flexible substrate 30. In addition, four coil springs 46 are soldered to the flexible substrate 30 so that the current supplied through the substrate pattern of the flexible substrate 30 is supplied to each driving coil via each coil spring 46. It has become.

  The movable portion 24 is a substantially rectangular resin member, and an opening 24a is provided at the center thereof, and an image blur prevention lens 26 is attached thereto. In addition, three circular recesses (not shown) are provided around the opening 24 a on the back surface side of the movable portion 24. These recesses are provided at positions facing the recesses 22b of the base member 22 and receive the support balls 42, respectively. As a result, each support ball 42 is held between the base member 22 and the movable portion 24 and is supported in a movable manner in a plane perpendicular to the optical axis A by rolling in each recess. To do. In the present embodiment, each support ball 42 is a sphere made of stainless steel.

  On the other hand, on the front side of the movable portion 24, the attracting magnet 36 and the back yoke 34 are embedded in four places around the opening 24a. The attracting magnet 36 and the back yoke 34 are embedded at positions aligned with the attracting yoke 44 embedded in the base member 22. As a result, each attracting magnet 36 attracts the corresponding attracting yoke 44 to hold each support ball 42 between the movable portion 24 and the base member 22, and the movable portion 24 is maintained parallel to the base member 22. Is done.

  In addition, a position detection magnet 38a and a position detection yoke 40, and a position detection magnet 38b and a position detection yoke 40 are attached to one end portion on the front side of the movable portion 24, respectively. The position detection magnet 38 a is disposed so as to face the Hall element 32 a attached to the flexible substrate 30, and the position detection magnet 38 b is arranged so as to face the Hall element 32 b attached to the flexible substrate 30. The position detection magnet 38 a is magnetized so that the magnetization boundary line C is directed in the longitudinal direction of the movable portion 24. For this reason, when the movable part 24 is displaced in a direction perpendicular to the longitudinal direction, the magnetism detected by the Hall element 32a changes, and the position displacement of the movable part 24 in this direction can be detected. Further, the position detecting magnet 38 b is magnetized so that the magnetization boundary line C is directed in the direction of the short side of the movable portion 24. For this reason, when the movable part 24 is displaced in the longitudinal direction, the magnetism detected by the Hall element 32b changes, and the displacement of the movable part 24 in this direction can be detected.

  Further, the first set of drive coils 48a and 48b and the second set of drive coils 50a and 50b are provided at the end of the movable portion 24 opposite to the position detection magnet. It is attached in the direction of. These first and second sets of driving coils together with the driving magnets 52 a and 52 b and the driving magnet yoke 54 attached to the base member 22 constitute driving means. This driving means drives the movable portion 24 in the first direction and the second direction within a plane orthogonal to the optical axis A. As described above, in the image stabilization actuator 20 according to the present embodiment, the driving unit is collectively arranged on one side of the image stabilization lens 26.

  The first set of driving coils 48a and 48b is a coil in which a winding is wound in a rectangular shape with rounded corners, and the driving coil 48a and the driving coil 48b have the same shape. The drive coils 48a and 48b are disposed adjacent to each other on the same plane orthogonal to the optical axis A. A straight line L2 (FIG. 7) passing between the drive coil 48a and the drive coil 48b is directed in the longitudinal direction of the movable portion 24. When a current flows through the first set of drive coils 48a and 48b, A driving force in the direction of the short side of the movable portion 24 that is the first direction (the direction of the straight line L1 in FIG. 7) is generated.

  The second set of driving coils 50a and 50b is a coil in which windings are wound in a rectangular shape with rounded corners, and the driving coil 50a and the driving coil 50b have the same shape. The driving coils 50a and 50b are arranged adjacent to each other on the same plane orthogonal to the optical axis A. A straight line L1 (FIG. 7) passing between the drive coil 50a and the drive coil 50b is directed in the direction of the short side of the movable portion 24, and current flows through the second set of drive coils 50a and 50b. Then, a driving force in the longitudinal direction of the movable portion 24 in the second direction (the direction of the straight line L2 in FIG. 7) is generated.

  Further, the first set of driving coils 48a and 48b are disposed so as to overlap the second set of driving coils 50a and 50b in FIG. That is, the first set of driving coils 48a and 48b and the second set of driving coils 50a and 50b are arranged so as to overlap in the direction of the optical axis A, and the first set of driving coils 48a, 48b and the second set of driving coils 50a and 50b are arranged so as to overlap in the projection in the direction of the optical axis A.

  Further, the length of the long side of the first set of driving coils 48a and 48b is approximately twice the length of the short side of the second set of driving coils 50a and 50b. The lengths of the long sides of the second set of driving coils 50a and 50b are approximately twice the length of the short sides of the first set of driving coils 48a and 48b. Therefore, the rectangle surrounding the first set of driving coils 48a and 48b arranged adjacent to each other and the rectangle surrounding the second set of driving coils 50a and 50b arranged adjacent to each other are almost the same shape. Thus, in the projection in the direction of the optical axis A, the first set of driving coils and the second set of driving coils almost completely overlap each other.

  As shown in FIG. 4, the drive magnet yoke 54 is a metal plate bent in a generally U shape, and is attached to the base member 22 sideways so that the side is open. In the U-shaped open portion of the drive magnet yoke 54, first and second sets of drive coils attached to the end of the movable portion 24 are arranged.

  As shown in FIGS. 4 and 6, the drive magnets 52 a and 52 b are rectangular parallelepiped magnets, and are attached inside the U-shape of the drive magnet yoke 54 so as to face each other in the direction of the optical axis A. ing. In addition, the driving magnet 52a disposed on the upper side in FIG. 6 is magnetized so that the upper surface side is the S pole and the lower surface side is the N pole, and the driving magnet 52b disposed on the lower side is the S pole on the upper surface side. It is magnetized so that the lower surface side is an N pole. Thereby, the magnetic lines of force from the upper side to the lower side in FIG. 4 pass through the first and second sets of driving coils disposed between the driving magnet 52a and the driving magnet 52b.

  Further, as indicated by a thick arrow C1 in FIG. 7, reverse currents flow through the first set of driving coils 48a and 48b. For this reason, currents in the same direction always flow through adjacent winding portions of the first set of driving coils 48a and 48b. Similarly, as indicated by a thin arrow C2 in FIG. 7, reverse currents flow through the second set of driving coils 50a and 50b. For this reason, currents in the same direction always flow through adjacent winding portions of the second set of driving coils 50a and 50b.

  On the other hand, as indicated by imaginary lines in FIG. 7, the drive magnets 52a and 52b are arranged so as to face the winding portions where currents in the same direction flow in the first and second sets of drive coils. , Mainly, a magnetic field is formed in this winding part. The first set of driving coils 48 a and 48 b are arranged on both sides of a straight line L <b> 2 in the second direction directed in the longitudinal direction of the movable portion 24. Therefore, when a current flows through the adjacent winding portions of the first set of driving coils 48a and 48b, a driving force is generated along the straight line L1 in the first direction perpendicular to the second direction. The On the other hand, the second set of driving coils 50a and 50b are arranged on both sides of a straight line L1 in the first direction directed in the direction of the short side of the movable portion 24. For this reason, when a current flows through adjacent winding portions of the second set of driving coils 50a and 50b, a driving force is generated along the straight line L2 in the second direction perpendicular to the first direction. The

  Next, as shown in FIGS. 5 to 7, the four coil springs 46 that are elastic members are provided so as to extend in the direction of the optical axis A, and the flexible substrate 30 attached to the cover 28 and the movable portion 24 are connected. It is connected. That is, the coil spring 46 functions as a movable part support unit that supports the movable part 24 movably with respect to the base member 22 in a plane orthogonal to the optical axis A. These coil springs 46 are elongate coil springs wound with a metal wire made of a very thin non-magnetic material, and are bent and expanded / contracted with a small force, so that the flexible substrate 30 and the movable portion 24 are connected by the coil springs 46. Even if it is done, the movable part 24 can be moved with a small force.

  Further, the force for returning the movable portion 24 to the initial position by the restoring force of the coil spring 46 is also small. Furthermore, even if there is an error in the dimensional accuracy and mounting accuracy of each coil spring 46, etc., the restoring force itself of each coil spring 46 is small, so that adverse effects due to variations in the restoring force of each coil spring 46 can be minimized. . Further, since the coil spring 46 is made of a nonmagnetic material, the coil spring 46 is not attracted by the magnetism of the driving magnets 52a and 52b disposed in the vicinity thereof, and avoids disturbance due to the magnetic force received from the driving magnet. Can do. Thus, in this embodiment, since a thin coil spring is used as an elastic body that supports the movable part, the movable part can be moved with an extremely small force compared to the case where a wire of the same thickness is used. Can be made.

  Further, as shown in FIG. 7, the four coil springs 46 are arranged so as to be positioned at the vertices of a rectangle surrounding the first and second sets of driving coils, respectively. The center of the rectangle formed by the four coil springs 46 is a straight line L2 extending between the first set of drive coils 48a and 48b and a straight line extending between the second set of drive coils 50a and 50b. It coincides with the intersection with L1. Accordingly, the four coil springs 46 are disposed at positions symmetrical with respect to the straight line L1, and are also disposed at positions symmetrical with respect to the straight line L2. As a result, the driving force generated by the first and second sets of driving coils and the restoring force of each coil spring 46 act in a well-balanced manner. For this reason, when a current flows through the first set of driving coils 48a and 48b and a driving force in the first direction is generated, the movable portion 24 is translated in the first direction. Similarly, when a current flows through the second set of driving coils 50a and 50b and a driving force in the second direction is generated, the movable portion 24 is translated in substantially the second direction.

Next, the operation of the image pickup apparatus 1 incorporating the vibration-proof actuator 20 according to the embodiment of the present invention will be described.
First, when the imaging device 1 is activated, the gyro 56 provided in the housing 2 detects a shake of the imaging device 1. A controller (not shown) built in the image pickup apparatus 1 is based on the shake angular velocity detected by the gyro 56 and is an image shake prevention lens to be moved to suppress the shake of the image formed on the image sensor 18. 26 command positions are calculated. On the other hand, the Hall element 32a attached to the flexible substrate 30 detects the displacement of the position detection magnet 38a attached to the movable portion 24 in the first direction (the direction of the straight line L1), and the image blur prevention lens 26 is detected. The position in the first direction is detected. Similarly, the Hall element 32b detects the displacement of the position detection magnet 38b in the second direction (the direction of the straight line L2), and detects the position of the image blur prevention lens 26 in the second direction.

  The position of the image blur prevention lens 26 detected by the hall elements 32a and 32b is sent to a controller (not shown) and compared with the command position calculated based on the detection signal of the gyro 56. The controller generates a driving force in the first direction and the second direction so that the detected position of the image blur prevention lens 26 approaches the command position. That is, the controller causes a current to flow through the first set of driving coils 48 a and 48 b via the flexible substrate 30 and the coil spring 46 to generate a driving force in the first direction. Similarly, the controller applies a current to the second set of driving coils 50 a and 50 b via the flexible substrate 30 and the coil spring 46 to generate a driving force in the second direction.

  In the present embodiment, the first set of driving coils 48a and 48b has a current in a direction indicated by an arrow C1 in FIG. 7 (clockwise for the driving coil 48a and counterclockwise for the driving coil 48b. ) Flows, the upward driving force in FIG. 7 acts on the first set of driving coils, and the image blur prevention lens 26 is moved upward. Further, when a current in the direction opposite to the arrow C1 (counterclockwise in the driving coil 48a and clockwise in the driving coil 48b) flows, the image blur prevention lens 26 moves downward in FIG. Is done.

  Furthermore, when a current in the direction indicated by an arrow C2 in FIG. 7 flows through the second set of driving coils 50a and 50b (clockwise for the driving coil 50a and counterclockwise for the driving coil 50b). The left driving force in FIG. 7 acts on the second set of driving coils, and the image blur prevention lens 26 is moved to the left. When a current in the direction opposite to the arrow C2 (counterclockwise in the driving coil 50a and clockwise in the driving coil 50b) flows, the image blur prevention lens 26 moves to the right in FIG. Moved.

  In this way, a reverse current always flows through the driving coils arranged adjacent to each other, and a current in the same direction always flows through the adjacent winding portions of the driving coils. Further, in each set of driving coils, currents in opposite directions flow through winding portions that are not adjacent to each other, but since the driving magnets 52a and 52b are not opposed to these winding portions, The magnetic field acting on the winding portion is weak and the generated electromagnetic force is small. In addition, since the displacement amount at the time of actual use of the vibration proof actuator 20 is very small, even when the movable part 24 is moved, a strong magnetic field does not act on winding portions that are not adjacent to each other.

  Due to the driving force generated as described above, the movable portion 24 and the image blur prevention lens 26 attached to the movable portion 24 are always moved so as to follow the command position, and the image focused on the image sensor 18 is moved. Swing is suppressed.

  According to the vibration-proof actuator 20 of the embodiment of the present invention, the first set of drive coils 48a and 48b and the second set of drive coils 50a and 50b are adjacent to each other on the same plane orthogonal to the optical axis A. And is arranged so as to overlap in the projection in the direction of the optical axis A (FIG. 5), so that the drive means can be made compact and the vibration-proof actuator 20 can be miniaturized. As a result, the anti-vibration actuator 20 of the present embodiment can be used for the thin imaging device 1 using the optical system in which the optical axis A is bent 90 ° in the middle as shown in FIGS. become. In addition, each set of driving coils is arranged so as to overlap in the projection in the direction of the optical axis A (FIG. 7). It becomes possible to generate the driving force in the two directions L2.

  Further, according to the vibration-proof actuator 20 of the present embodiment, the four coil springs 46 are arranged at positions symmetrical with respect to the straight line L1 in the first direction and the straight line L2 in the second direction (FIG. 7). Therefore, the restoring force by each coil spring 46 acts in a well-balanced manner, and the generation of moment due to the driving force generated by the first and second sets of driving coils is suppressed. For this reason, the movable portion 24 is translated in substantially the first and second directions by the driving force generated by the first and second sets of driving coils.

  Furthermore, according to the vibration-proof actuator 20 of the present embodiment, the coil spring 46 is used as a current conductor that flows through each driving coil, so there is no need to provide a separate conductor for guiding the current, and the number of parts can be reduced. The assemblability of the vibration isolation actuator 20 can be improved. Further, disturbance due to the movement of the movable portion 24 caused by separately providing a conductor for guiding current can be removed.

  Further, according to the vibration-proof actuator 20 of the present embodiment, since the four coil springs 46 are made of a nonmagnetic material, each coil spring 46 receives the magnetic force from the drive magnets 52a and 52b, and the movable part 24 moves. Can be prevented.

  Furthermore, in the vibration proof actuator 20 of the present embodiment, the first set of drive coils is composed of two substantially identical drive coils 48a and 48b having a rectangular shape, and the second set of drive coils is substantially the same. It is composed of two rectangular driving coils 50a and 50b, and the length of the long side of the first set of driving coils 48a and 48b is the short side of the second set of driving coils 50a and 50b. The length of the long side of the second set of driving coils 50a and 50b is approximately twice the length of the short side of the first set of driving coils 48a and 48b. (FIG. 7). With this configuration, the maximum driving coil can be arranged within the same projected area in the direction of the optical axis A, and a large driving force can be obtained by the first and second driving coils having a small exclusive area. Can be generated.

  Further, in the vibration proof actuator 20 of the present embodiment, reverse currents flow through the first set of driving coils 48a and 48b so that currents in the same direction flow in adjacent winding portions, In the second set of driving coils 50a and 50b, reverse currents flow so that currents in the same direction flow in adjacent winding portions, and the driving magnets 52a and 52b A magnetic field is formed in the winding portion of the second set of driving coils through which current in the same direction flows (FIG. 7). With this configuration, the driving magnets 52a and 52b form a magnetic field mainly in the winding portion where the current in the same direction flows, so that the driving force can be generated efficiently.

  Furthermore, in the vibration-proof actuator 20 of the present embodiment, two drive magnets 52a and 52b are provided so as to face the optical axis A direction, and a first set of magnets is provided between the drive magnets 52a and 52b. Driving coils 48a and 48b and a second set of driving coils 50a and 50b are arranged. With this configuration, the magnetic field acting on the first set of drive coils 48a and 48b and the second set of drive coils 50a and 50b can be strengthened. Thereby, each drive coil and drive magnet 52a, 52b can be comprised small, and the vibration-proof actuator 20 can be reduced further.

  As mentioned above, although preferable embodiment of this invention was described, a various change can be added to embodiment mentioned above. In particular, in the above-described embodiment, the driving coil is attached to the movable part and the driving magnet is attached to the base member. However, the driving magnet is attached to the movable part, and the driving coil is attached to the fixed side. In addition, the present invention can also be configured.

  In the above-described embodiment, the two drive magnets are arranged so as to face each set of drive coils, but one drive magnet may be provided. Further, the drive magnet is not necessarily arranged so as to face the drive coil, and the present invention can be configured so that the magnetic field is guided to the drive coil by the yoke.

DESCRIPTION OF SYMBOLS 1 Imaging device 2 Case 4 Prism 6 1st lens (imaging lens)
8 Second lens (imaging lens)
10 Third lens (imaging lens)
12 Fourth lens (imaging lens)
14 Fifth lens (imaging lens)
Reference Signs List 16 Shutter Unit 18 Image Sensor 20 Anti-Vibration Actuator 22 Base Member 22a Opening 22b Recess 22c Cutout 24 Moving Part 24a Opening 26 Image Stabilization Lens 28 Cover 28a Opening 28b Cutout 30 Flexible Substrate 30a Opening 30b Cutout 32a, 32b Hall element (position detection means)
34 Back yoke 36 Adsorption magnets 38a, 38b Position detection magnet 40 Position detection yoke 42 Support ball (movable part support means)
44 Suction yoke 46 Coil spring (elastic member, movable part support means)
48a, 48b First set of drive coils 50a, 50b Second set of drive coils 52a, 52b Drive magnet 54 Drive magnet yoke 56 Gyro

Claims (7)

An anti-vibration actuator for moving the image blur prevention lens,
A fixed portion fixed to the housing;
A movable part to which the lens for preventing image blur is attached;
Movable part support means for supporting the movable part movably with respect to the fixed part within a plane perpendicular to the optical axis of the image blur prevention lens;
Drive means for driving the movable part in a first direction and a second direction different from the first direction in a plane orthogonal to the optical axis;
The drive means is
A drive magnet attached to either the fixed part or the movable part;
Two sets of driving coils that are attached to the fixed part and the movable part that are not attached with the driving magnet and generate a driving force by interaction with the magnetic field formed by the driving magnet; Have
A first set of driving coils among the driving coils is disposed adjacent to the same plane perpendicular to the optical axis so as to generate a driving force in the first direction. Of the coils, the second set of driving coils is arranged on the optical axis different from the plane on which the first set of driving coils is arranged so as to generate the driving force in the second direction. The first set of driving coils and the second set of driving coils are arranged adjacent to each other on the same orthogonal plane, and are arranged so as to overlap in the projection in the optical axis direction. Anti-vibration actuator characterized.   The movable portion support means includes four elastic members extending in the optical axis direction between the fixed portion and the movable portion, and the four elastic members are the first set of driving coils. 2. The prevention according to claim 1, wherein the first direction straight line extending between the second set of driving coils and the first direction straight line extending between the second set of driving coils are symmetrically arranged. Vibration actuator.   The anti-vibration actuator according to claim 2, wherein the four elastic members are made of a conductive material, and the four elastic members are used as conductors of a current flowing through the two sets of driving coils.   4. The vibration-proof actuator according to claim 2, wherein the four elastic members are made of a nonmagnetic material.   The first set of drive coils is composed of two rectangular drive coils having the same shape, and the second set of drive coils is composed of two rectangular drive coils having the same shape. The length of the long side of the first set of drive coils is approximately twice the length of the short side of the second set of drive coils, and the long side of the second set of drive coils. 5. The vibration-proof actuator according to claim 1, wherein the length of the vibration-proof actuator is approximately twice the length of the short side of the first set of driving coils.   In the first set of driving coils, reverse currents flow so that currents in the same direction flow in adjacent winding portions, and the second set of driving coils have adjacent windings. Currents in opposite directions flow so that currents in the same direction flow in the line portion, and the driving magnet is a winding through which the currents in the same direction of the driving coils of the first group and the second group flow. 6. The vibration-proof actuator according to claim 1, wherein a magnetic field is formed in the portion.   Two of the drive magnets are provided so as to face the optical axis direction, and the first set of drive coils and the second set of drive coils are arranged between the drive magnets. The vibration-proof actuator according to any one of claims 1 to 6.

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