JP2019095503A - Actuator, and lens unit as well as camera including the same - Google Patents

Abstract

To provide an actuator that can generate large driving force without increasing an external diameter of a lens barrel.SOLUTION: The present invention relates to an actuator (10) that corrects image tremors. The actuator comprises: a stationary part (12); a movable part (14) that has an image tremor correction-purpose lens (16) attached thereto; movable part supporting means (18) that supports the movable part; three or more driving-purpose coil assemblies (20, 21 and 22) that are arranged around an optical axis of the movable part; and three or more driving-purpose magnetic assemblies (23, 24 and 25) that are provided in the stationary part so as to face the driving-purpose coil assemblies, respectively. Each of the driving-purpose coil assemblies is composed of three or more coils juxtaposed adjacently to each other, and center points of the coils arranged at an end on either side of these coils pass through a center point of the coil arranged at a center part, and are located on a side near an optical axis with respect to a linear line in contact with a circle with the optical axis as a center.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an actuator, and more particularly to an actuator for moving an image blur correction lens in a plane perpendicular to the optical axis to correct image blur, a lens unit provided with the same, and a camera.

  Japanese Patent Application Laid-Open No. 2016-170339 (Patent Document 1) describes a shake correction device that drives an imaging device within a predetermined plane. The shake correction apparatus captures an image of the movable portion with respect to the fixed portion, the movable portion including the fixed portion in which the plurality of coils are disposed, the plurality of magnets disposed facing the plurality of coils, and the imaging device. And a supporting member movably supported along a plane perpendicular to the optical axis of light incident on the element. Furthermore, the shake correction apparatus includes detection means for detecting the position of the movable portion, and control means for controlling the current supplied to the plurality of coils based on the output of the detection means. The plurality of coils form three coil groups, with two coils arranged opposite to each other along a plane perpendicular to the optical axis as one coil group, and constitute each coil group The driving forces generated by the two coils are configured to be different from each other.

JP, 2016-170339, A

  In the shake correction device described in Patent Document 1, since a total of six driving coils of three groups are provided, a large driving force for driving the imaging device can be easily obtained. However, in the shake correction device described in Patent Document 1, coils for driving each drive and magnets for driving each provided to face them are disposed so as to fill the back side of the imaging device. On the other hand, in an actuator that drives an image blur correction lens to correct blur of a captured image, a drive coil and a magnet are disposed around the image blur correction lens. For this reason, if the drive coil and magnet are arranged as in the case of the vibration reduction device described in Patent Document 1, there is no space for arranging the image blur correction lens. Alternatively, when a space for disposing an image blur correction lens at the center of each drive coil is provided in the blur correction device described in Patent Document 1, a large space for disposing a coil around the image blur correction lens is obtained. The problem is that the lens barrel becomes large.

  Therefore, an object of the present invention is to provide an actuator capable of generating a large driving force without increasing the outer diameter of the lens barrel, and a lens unit and a camera provided with the same.

  In order to solve the problems described above, the present invention is an actuator for moving an image blur correction lens in a plane orthogonal to its optical axis to correct image blur, which is a fixed part, image blur correction A movable portion to which the movable lens is attached, a movable portion supporting means for supporting the movable portion on a plane orthogonal to the optical axis of the image blur correction lens with respect to the fixed portion, and a fixed portion or movable portion Provided so as to face each of the drive coil assemblies, respectively, on at least one of the three or more drive coil assemblies arranged around the optical axis and on the other of the fixed part or the movable part And three or more drive magnet assemblies each generating a driving force between the two coil assemblies, and each drive coil assembly is composed of three or more adjacently arranged coils. , These co The center points of the coils disposed at both ends of the loop pass through the center point of the coil disposed at the center portion, and the light is directed to a center tangent line that is a straight line tangent to a circle centered on the optical axis. It is characterized in that it is located closer to the axis.

  According to the present invention thus configured, the drive coil assembly has three or more drive coil assemblies disposed around the optical axis, and each drive coil assembly includes three or more adjacently arranged ones. The center points of the coils, which are composed of coils and are disposed at both ends of the coils, are located closer to the optical axis with respect to the center tangent. Therefore, in the actuator of the present invention, many coils can be disposed without waste in a limited space around the image blur correction lens, and a large driving force can be obtained without increasing the outer diameter of the lens barrel. You can get it.

  According to the actuator of the present invention, the lens unit including the same, and the camera, a large driving force can be generated without increasing the outer diameter of the lens barrel.

1 is a cross-sectional view of a camera according to a first embodiment of the present invention. It is side surface sectional drawing of the actuator with which the camera of 2nd Embodiment of this invention is equipped. It is a front view of the moving frame of the actuator with which the camera of 1st Embodiment of this invention is equipped. It is a front view of the stationary plate of the actuator with which the camera of a 1st embodiment of the present invention is equipped. It is a front view of the moving frame of the actuator in the modification of a 1st embodiment of the present invention. It is a front view of the moving frame of the actuator with which the camera of 2nd Embodiment of this invention is equipped. It is a front view of the moving frame of the actuator in the modification of the present invention. It is a front view of the moving frame of the actuator with which the camera of 3rd Embodiment of this invention is equipped.

First Embodiment
Embodiments of the invention will now be described with reference to the accompanying drawings. First, a camera according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1 is a cross-sectional view of a camera according to an embodiment of the present invention.

<Configuration of camera>
As shown in FIG. 1, the camera 1 according to the embodiment of the present invention includes a lens unit 2 and a camera body 4. The lens unit 2 includes a lens barrel 6, a plurality of lenses 8 disposed in the lens barrel, and an image blur correcting lens 16 for moving the image blur in a plane perpendicular to the optical axis. And the gyro 34 which is a vibration detection means for detecting the vibration of the lens barrel 6.

  The camera 1 according to the embodiment of the present invention detects vibration by the gyro 34 and operates the actuator 10 based on the detected vibration to move the image blur correction lens 16, and the image pickup device surface 4 a in the camera body 4. Stabilize the image that is focused on. In the present embodiment, a piezoelectric vibration gyro is used as the gyro 34. In the present embodiment, the image blur correction lens 16 is configured of one lens, but the lens for stabilizing the image may be a plurality of lens groups. In the present specification, the image blur correction lens includes one lens and a lens group for stabilizing an image.

  The lens unit 2 is attached to the camera body 4 and is configured to form an incident light on the imaging element surface 4a. The substantially cylindrical lens barrel 6 holds a plurality of lenses 8 therein, and enables focus adjustment by moving some of the lenses 8.

<Structure of Actuator>
Next, with reference to FIGS. 2 to 4, an actuator 10 for image shake correction according to an embodiment of the present invention will be described. FIG. 2 is a side sectional view of the actuator 10. FIG. 3 is a front view of a moving frame of the actuator 10, and FIG. 4 is a front view of a fixed plate of the actuator 10. As shown in FIG.

  As shown in FIGS. 2 to 4, the actuator 10 is a fixed plate 12 which is a fixed part fixed in the lens barrel 6, and a movable plate supported for translational movement and rotational movement with respect to the fixed plate 12. A moving frame 14 which is a part, and three steel balls 18 which are movable part supporting means for supporting the moving frame 14 with respect to the fixed plate 12. At the center of the moving frame 14, an image stabilizing lens 16 is attached, and three steel balls 18 are disposed around the lens 16.

  As shown in FIGS. 2 and 4, three steel balls 18 are held between the fixed plate 12 and the moving frame 14 and have a central angle of 120 ° on the circumference of a circle centered on the optical axis A. They are spaced apart. Each steel ball 18 is disposed in a recess 30 formed at a position corresponding to each steel ball 18 of the fixing plate 12 to prevent falling off. Thereby, the moving frame 14 is supported in parallel to the fixed plate 12 on a plane orthogonal to the optical axis A, and the steel balls 18 are rolled while being held, thereby moving the moving frame 14 in any direction relative to the fixed plate 12. Translational and rotational movements are allowed.

  Further, in the present embodiment, a steel ball is used as the steel ball 18, but for example, the moving frame 14 can be supported on the fixed plate 12 by a resin ball. In addition, the moving frame can be supported by a sliding surface that can slide smoothly without using steel balls, and the moving frame can be supported movably in a plane perpendicular to the optical axis with respect to the fixed plate. Any movable part support means can be used.

  Furthermore, as shown in FIGS. 2 and 3, the actuator 10 has a first drive coil assembly 20, a second drive coil assembly 21, and a third drive coil assembly 22 attached to the moving frame 14. A first magnetic sensor 26a, a second magnetic sensor 26b, and a third magnetic sensor 26c are respectively provided in the first, second and third drive coil assemblies. Further, as shown in FIGS. 2 and 4, the actuator 10 has a first drive magnet assembly 23, a second drive magnet assembly 24 and a third drive magnet assembly 25 attached to the fixed plate 12.

  Furthermore, as shown in FIG. 1, the actuator 10 is based on the vibration detected by the gyro 34 and the positional information of the moving frame 14 detected by the first, second and third magnetic sensors 26a, 26b and 26c. And a controller 36 that is a control unit that controls the current supplied to the first, second, and third drive coil assemblies 20, 21, 22.

  Further, the controller 36 controls the actuator 10 to translate the moving frame 14 in a plane parallel to the imaging element surface 4 a with respect to the fixed plate 12 fixed to the lens barrel 6. As a result, the image blur correction lens 16 attached to the moving frame 14 is moved, and even when the lens barrel 6 vibrates, the shake of the image formed on the imaging element surface 4 a is suppressed.

  Next, as shown in FIGS. 2 and 3, the moving frame 14 has a flat plate portion 14 a having a generally donut shape and a cylindrical portion 14 b formed at the center thereof so as to overlap in parallel with the fixed plate 12. It is arranged. An image blur correction lens 16 is attached to the inside of the cylindrical portion 14b.

  As shown in FIG. 3, first, second and third drive coil assemblies 20, 21 and 22 are attached on the circumference of a circle centered on the optical axis A of the flat plate portion 14 a. The first, second and third drive coil assemblies 20, 21 and 22 are opposed to the first, second and third drive magnet assemblies 23, 24 and 25 attached to the fixed plate 12, Each drive magnet assembly is mounted at a corresponding position. That is, in the present embodiment, the first, second and third drive coil assemblies 20, 21 and 22 are arranged at equal intervals on the circumference of a circle centered on the optical axis A, and for the first drive The coil assembly 20 is disposed vertically above the optical axis A.

  In addition, the first, second and third drive coil assemblies 20, 21 and 22 are respectively composed of three coils arranged adjacent to each other. That is, the first drive coil assembly 20 is composed of a center coil 20a, which is a coil disposed at the center, and two side coils 20b and 20c disposed adjacent to each other on both sides thereof. Similarly, the second drive coil assembly 21 includes a center coil 21a and two side coils 21b and 21c, and the third drive coil assembly 22 includes a center coil 22a and two side coils 22b and 22c. ing. The side coils on both sides of the center coil have the same configuration. In addition, the first to third drive coil assemblies have the same configuration except for the direction in which they are arranged on the moving frame 14. Therefore, the configuration of the first drive coil assembly 20 will be mainly described below.

  The center coil 20a and the side coils 20b and 20c that constitute the first drive coil assembly 20 are flat coils in which the leads are wound in a substantially rectangular shape with rounded corners. The center coil 20a is arranged such that the center line crossing the short side is directed in the radial direction of a circle centered on the optical axis A. Similarly, the center coils 21a and 22a of the second and third drive coil assemblies are also arranged such that their short sides are in the tangential direction of a circle centered on the optical axis A. In addition, the first magnetic sensor 26a is disposed inside the center coil 20a, and similarly, the second magnetic sensor 26b is disposed inside the center coil 21a, and the third magnetic sensor 26c is disposed inside the center coil 22a. ing.

  Further, the side coils 20b and 20c constituting the first drive coil assembly 20 are respectively disposed adjacent to both sides of the center coil 20a. That is, one side (side) of the center coil 20a is disposed to be adjacent in parallel to one side (side) of the side coil 20b, and the other side (side) of the center coil 20a is provided adjacent to the side coil 20c. It is arranged to be adjacent in parallel to one side (side).

Furthermore, the center point S ₁ of the center coil 20a is located on a circle C centered on the optical axis A. The center points S ₂ and S _{3 of} the side coils 20 b and 20 c are also located on the circle C, similarly to the center point S ₁ of the center coil 20 a. Therefore, the center points S ₂ and S ₃ of the side coils 20 b and 20 c are located closer to the optical axis A with respect to the center tangent T which is a straight line passing through the center point S ₁ and contacting the circle C. . Also in the second and third drive coil assemblies, the center coils and the side coils are arranged in the same positional relationship.

  Further, the center coil 20a is larger in outer shape than the side coils 20b and 20c, and is formed longitudinally long (long in the radial direction of a circle centered on the optical axis). That is, the width of each side coil 20b, 20c in the direction perpendicular to the center tangent T is narrower than that of the center coil 20a. In other words, the center coil 20a has an aspect ratio, which is a value obtained by dividing the length in the direction perpendicular to the central tangent T by the length in the central tangent T direction, from the side coils 20b and 20c arranged on both sides. Is also formed large.

  Further, each side coil 20b, 20c is formed with a larger number of turns of the conducting wire than the center coil 20a, and the inner diameter thereof (width inside the coil) is formed smaller than the inner diameter of the center coil 20a. .

  Next, as shown in FIG. 4, the fixed plate 12 has a generally donut shape, in which first, second and third drive magnet assemblies 23, 24 and 25 are embedded, respectively. . The first, second and third drive magnet assemblies 23, 24 and 25 are arranged on the circumference of a circle C centered on the optical axis A so as to face the first to third drive coil assemblies respectively. The central angles are spaced at equal intervals of 120 °. In the present embodiment, the first drive magnet assembly 23 facing the first drive coil assembly 20 is disposed vertically above the optical axis A.

  The first drive magnet assembly 23 is composed of four drive magnets 23a, 23b, 23c and 23d arranged adjacent to each other. Similarly, the second drive magnet assembly 24 comprises four drive magnets 24a, 24b, 24c and 24d, and the third drive magnet assembly 25 comprises four drive magnets 25a, 25b, 25c and 25d. ing. Also, since the first to third drive magnet assemblies have the same configuration except for the direction in which they are disposed on the fixed plate 12, the configuration of the first drive magnet assembly 23 will be mainly described below.

  The four drive magnets 23a, 23b, 23c, and 23d constituting the first drive magnet assembly 23 are each formed in a rectangular plate shape. The drive magnets 23a, 23b, 23c and 23d are disposed symmetrically two on each side of the axis Q directed in the radial direction of the circle C centered on the optical axis A, and the length of each drive magnet The sides are oriented parallel to the symmetry axis Q respectively.

  Furthermore, central points Sb and Sc of the two drive magnets 23b and 23c disposed at the central portion of the first drive magnet assembly 23 pass through the intersection of the circle C centered on the optical axis A and the symmetry axis Q. , Located on a central tangent line T in contact with the circle C. On the other hand, the center points Sa and Sd of the two drive magnets 23a and 23d disposed at both ends of the first drive magnet assembly 23 are closer to the optical axis A with respect to the center tangent T. It is located in

  Further, as shown in FIG. 2, each drive magnet constituting the first drive magnet assembly 23 is magnetized so as to have different magnetic poles on the front and back surfaces. As shown in FIG. 4, in the present embodiment, the four drive magnets 23a, 23b, 23c, and 23d have N poles, S poles, N poles, in order (surfaces facing the drive coil assembly). It is magnetized to be a south pole.

  Furthermore, as shown by an imaginary line in FIG. 3, one drive magnet 23 c constituting the first drive magnet assembly 23 is one side (side) of the center coil 20 a constituting the first drive coil assembly 20. , And one side (side) of the side coil 20b adjacent to this, and it is arrange | positioned so as to oppose. The driving magnet 23b is disposed to face the other side (side) of the center coil 20a and one side (side) of the side coil 20c adjacent thereto. On the other hand, the drive magnet 23a disposed at the end of the first drive magnet assembly 23 faces only one side (side) of the side coil 20c, and the drive magnet 23d is one side (side) of the side coil 20b. ) And only facing.

  Further, the first drive coil assembly 20 is configured such that current in the same direction always flows on one side (side) of the center coil 20a and one side (side) of the side coil 20c adjacent thereto. It is done. Similarly, a current in the same direction always flows through the other side (side) of the center coil 20a and one side (side) of the side coil 20b adjacent thereto. That is, in the present embodiment, the first drive coil assembly 20 is formed of a single lead, and the lead is wound around the center coil 20a and the side coils 20b and 20c adjacent thereto in opposite directions. For example, when the center coil 20a is wound clockwise, the side coils 20b and 20c are wound counterclockwise, and the leads of these coils are continuous.

  In the first drive coil assembly 20, current flows in such a direction, and the magnetic poles of the drive magnets of the first drive magnet assembly 23 opposed thereto are oriented as described above. As a result, when current is supplied to the first drive coil assembly 20, a drive force in a direction parallel to the central tangent T is generated between the first drive coil assembly 20 and the first drive magnet assembly 23. Do. Similarly, between the second drive coil assembly 21 and the second drive magnet assembly 24, and between the third drive coil assembly 22 and the first drive magnet assembly 25, a direction parallel to the respective center tangent T. Driving force is generated.

  Also, as shown in FIG. 4, back yokes 32 are provided on the back side of the first, second and third drive magnet assemblies respectively, and on the back side of the first, second and third drive coil assemblies. The closed magnetic yokes 33 are respectively provided (FIG. 4 shows only the back yoke 32 on the back side of the first drive magnet assembly 23 and the closed magnetic yoke 33 on the back side of the first drive coil assembly 20). The back yoke 32 and the closed magnetic yoke 33 are made of a ferromagnetic material such as iron, stainless steel, electromagnetic steel plate, etc., whereby the magnetic flux of the drive magnet is efficiently directed to the drive coil, and the closed magnetic path Is formed.

<Action of actuator>
The operation of the camera 1 according to an embodiment of the present invention will now be described with reference to FIG. First, when the start switch (not shown) of the image shake correction function of the camera 1 is turned on, the actuator 10 provided in the lens unit 2 is operated. The gyro 34 attached to the lens unit 2 detects the vibration of a predetermined frequency band every moment and outputs it to the controller 36. A lens position command signal is generated based on the signal of the angular velocity detected by the gyro 34. By moving the image blur correction lens 16 momentarily to a position commanded by the lens position command signal, an image focused on the image pickup device surface 4 a of the camera body 4 is stabilized.

  The position of the moving frame 14 to which the image blur correction lens 16 is attached is specified by each of the magnetic sensors 26a, 26b, 26c detecting the magnetic flux formed by each driving magnet assembly. When the detected position of the moving frame 14 reaches the position designated by the lens position command signal, the current flowing to each coil of each drive coil assembly is zeroed, and the driving force is also zeroed.

  In addition, when the moving frame 14 deviates from the position designated by the lens position command signal due to disturbance or a change in the lens position command signal, current flows again to the center coil and the side coil of each drive coil assembly. When current flows in each coil, a driving force in the direction of central tangent T (FIG. 3) is generated between the drive magnet assembly disposed opposite to each drive coil assembly, and the moving frame 14 is positioned at the lens position. It is returned to the position designated by the command signal. The above operation is repeated every moment, so that the image stabilizing lens 16 attached to the moving frame 14 is moved so as to follow the lens position command signal. Thereby, the image focused on the imaging element surface 4 a of the camera body 4 is stabilized.

<Effect of actuator>
According to the actuator 10 of the embodiment of the present invention, it has three drive coil assemblies 20, 21 and 22 arranged around the optical axis A, and each drive coil assembly 20, 21 and 22 is adjacent to each other. The center coil 21a and the side coils 21b and 21c are arranged side by side (FIG. 3). For this reason, a large driving force can be generated between the drive coil assemblies 20, 21, 22 and the drive magnet assemblies 23, 24, 25 disposed opposite to each other. Also, among the coils of the drive coil assembly 20, the side coil 20b disposed on opposite ends, the center point S _2, S ₃ and 20c are to the center tangent line T passing through the center point S ₁ of the center coil 20a Is located closer to the optical axis A. For this reason, in the actuator 10 of the present embodiment, many coils can be disposed without waste in a limited space around the image blur correction lens 16, and the outer diameter of the lens barrel 6 is not increased. A large driving force can be obtained.

According to the actuator 10 of the present embodiment, by adopting the configuration as described above, the driving force is doubled without increasing the size of the conventional actuator (the drive coil assembly is formed of one coil) without increasing the size. Have succeeded in doing.
As a modification, according to the present invention, the outer shape of the actuator can be miniaturized while maintaining a predetermined driving force. That is, in the conventional actuator in which each drive coil comprises one coil, the external dimensions shown by the broken line in FIG. 5 are required in order to obtain the required drive force. On the other hand, as shown in FIG. 5, according to the present invention, the first, second and third drive coil assemblies 20 ', 21' and 22 each comprise three small drive coils. The first, second, and third drive magnet assemblies 23 ', 24', 25 'are respectively formed of four small drive magnets. As described above, the present invention is applied to the conventional actuator which required the outline shown by the broken line in FIG. 5, and the same driving force is maintained by making each driving coil into a coil assembly composed of a plurality of coils. As it is, we succeeded in downsizing as shown by the solid line.

  Further, according to the actuator 10 of the present embodiment, among the coils constituting the drive coil assembly 20, the side coils 20b and 20c disposed at the end portions on both sides are closer to the center coil 20a disposed at the central portion. The width in the direction perpendicular to the center tangent T is narrow. For this reason, many coils can be efficiently arranged in a toroidal space around the image blur correction lens 16.

  Furthermore, according to the actuator 10 of the present embodiment, each of the coils constituting the drive coil assembly 20 is formed in a substantially rectangular shape, and among these coils, the center coil 20a disposed at the central portion has its center tangent T The aspect ratio, which is a value obtained by dividing the length in the direction perpendicular to the direction by the length in the direction of the central tangent T, is formed larger than that of the side coils 20b and 20c disposed at the ends on both sides. For this reason, many coils can be efficiently arranged in a toroidal space around the image blur correction lens 16.

  Further, according to the actuator 10 of the present embodiment, among the coils constituting the drive coil assembly 20, the side coils 20b and 20c disposed at the end portions on both sides are closer to the center coil 20a disposed at the central portion. , The number of turns of the wire is formed. For this reason, a sufficiently large driving force can be obtained even by the side coils 20b and 20c whose width in the direction perpendicular to the center tangent T is narrower than that of the center coil 20a.

  Furthermore, according to the actuator 10 of the present embodiment, the inner diameters of the side coils 20b and 20c arranged at the ends of both sides of the coils constituting the drive coil assembly 20 are the center coil 20a arranged at the center. It is formed smaller than the inner diameter of. Therefore, even in the side coils 20b and 20c having a narrow width in the direction perpendicular to the central tangent T, the number of turns of the wire can be increased without increasing the thickness, and a sufficiently large driving force can be obtained.

  In the above-described embodiment of the present invention, a coil having an outer diameter smaller than that of the center coil is used for each side coil, but the actuator according to the present invention is not limited to this. For example, in the actuator according to the present invention, the outer shapes of the center coil and the side coils of the drive coil assembly may be the same. Also in this case, by arranging the center point of each side coil on the side closer to the optical axis with respect to the center tangent passing through the center point of the center coil, a large driving force can be obtained without increasing the size of the lens barrel. You can get

  Further, according to the actuator 10 of the present embodiment, the magnetic sensor 26 a is disposed inside the center coil 20 a disposed at the center of the coils constituting the drive coil assembly 20. Since the magnetic sensor is disposed inside the coil as described above, the magnetic sensor 26a can be disposed on the moving frame 14 without securing an additional space. Further, since the magnetic sensor 26a is disposed inside the center coil 20a, the magnetism of the opposing drive magnet assembly 23 acts symmetrically in the left-right direction, and the movement amount of the moving frame 14 can be detected with high accuracy.

  Furthermore, according to the actuator 10 of the present embodiment, the drive coil assembly 20 and the drive magnet assembly 23 disposed opposite to the drive coil assembly 20 generate a drive force in a direction parallel to the central tangent T. Is configured. Therefore, by arranging the plurality of coils adjacent to each other in the tangential direction of the circle centered on the optical axis, the driving force can be increased without complicating the structure.

  Further, according to the actuator 10 of the present embodiment, one drive magnet 23c constituting the drive magnet assembly 23 is one side of the center coil 20a disposed at the center of the three coils, and It is arrange | positioned so as to oppose one side of the adjacent side coil 20b. For this reason, even when the drive coil assembly includes many coils, the number of magnets in the drive magnet assembly opposed thereto can be reduced, and the structure can be simplified.

Second Embodiment
Next, a camera according to a second embodiment of the present invention will be described with reference to FIG. The camera of this embodiment differs from the first embodiment in the configuration of the built-in actuator. Therefore, only the points of the present embodiment different from the first embodiment will be described here, and the description of the same configuration, operation, and effects will be omitted.

<Structure of Actuator>
FIG. 6 is a front view of a moving frame of an actuator provided in a camera according to a second embodiment of the present invention. As shown in FIG. 6, the actuator 100 in the present embodiment is provided with three drive coil assemblies and three drive magnet assemblies, and each drive coil assembly consists of four coils. Is different from the first embodiment.

  That is, the actuator 100 includes a moving frame 114 which is a movable portion, an image blur correcting lens 116 attached thereto, a first drive coil assembly 120, a second drive coil assembly 121, and a third drive coil. It has an assembly 122. Furthermore, as shown by an imaginary line in FIG. 6, the fixing plate (not shown) of the actuator 100 is provided with a first drive magnet assembly 123 disposed opposite to the first to third drive coil assemblies, A second drive magnet assembly 124 and a third drive magnet assembly 125 are provided.

  First, as shown in FIG. 6, the first, second and third drive coil assemblies 120, 121 and 122 are arranged at equal intervals on the circumference of a circle centered on the optical axis A, and the first drive The coil assembly 120 is disposed vertically above the optical axis A.

  In addition, the first, second and third drive coil assemblies 120, 121 and 122 are each composed of four coils arranged adjacent to each other. That is, the first drive coil assembly 120 is composed of two center coils 120a and 120b which are coils disposed at the central portion thereof, and two side coils 120c and 120d which are disposed adjacent to each other on both sides thereof. It is done. Similarly, the second drive coil assembly 121 includes two center coils 121a and 121b and two side coils 121c and 121d, and the third drive coil assembly 122 includes two center coils 122a and 122b and two It comprises the side coils 122c and 122d. The two center coils and the side coils on both sides thereof have the same configuration. Also, since the first to third drive coil assemblies have the same configuration except for the direction in which they are arranged on the moving frame 114, the configuration of the first drive coil assembly 120 will be mainly described below.

  Each of the coils constituting the first drive coil assembly 120 is a flat coil whose lead wire is wound in a substantially rectangular shape with rounded corners. The two center coils 120a and 120b are disposed adjacent to each other on both sides of a straight line in the radial direction of a circle centered on the optical axis A, and their long sides are oriented parallel to the straight line in the radial direction. Similarly, the center coils of the second and third drive coil assemblies are also disposed adjacent to each other on both sides of the radial straight line, and their long sides are oriented parallel to the radial straight line. Also, in each coil assembly, first to third magnetic sensors (not shown) are respectively disposed inside one of the center coils.

  Further, the side coils 120c and 120d constituting the first drive coil assembly 120 are respectively disposed adjacent to both sides of the two center coils. That is, one side (side) of the center coil 120a is disposed to be adjacent in parallel to one side (side) of the side coil 120c, and the other side (side) of the center coil 120b is: The side coils 20d are arranged in parallel and adjacent to one side (side) of the side coil 20d. Although a slight gap is provided between the two center coils 120a and 120b, the center coil 120a and the side coil 120c, and the center coil 120b and the side coil 120d are in contact with each other.

Furthermore, as shown in FIG. 6, the center points S ₁₁ and S ₁₂ of the center coils 120 a and 120 b are located on the center tangent T which is a straight line contacting the circle C centered on the optical axis A. On the other hand, center points S ₁₃ and S ₁₄ of the side coils 120 c and 120 d are located closer to the optical axis A with respect to the center tangent T. Also in the second and third drive coil assemblies, the center coils and the side coils are arranged in the same positional relationship.

  Each of the center coils 120a and 120b is larger in outer shape than each of the side coils 120c and 120d, and is formed longitudinally long (longer in the radial direction of a circle centered on the optical axis). That is, the width of each side coil 120c, 120d in the direction perpendicular to the center tangent T is narrower than that of the center coil 120a, 120b. In other words, in the center coils 120a and 120b, the side coils 120c arranged on both sides have an aspect ratio which is a value obtained by dividing the length in the direction perpendicular to the central tangent T by the length in the central tangent T direction. It is formed larger than 120 d.

  Furthermore, each side coil 120c, 120d is formed so that the number of turns of the conducting wire is larger than that of the center coil 120a, 120b, and their inner diameter (width inside the coil) is formed smaller than the inner diameter of each center coil. ing.

  On the other hand, first, second and third drive magnet assemblies 123, 124 and 125 shown in phantom in FIG. 6 are embedded in the fixed plate (not shown), respectively. The first, second and third drive magnet assemblies 123, 124 and 125 are arranged on the circumference of a circle C centered on the optical axis A so as to face the first to third drive coil assemblies respectively. The central angles are spaced at equal intervals of 120 °. In the present embodiment, the first drive magnet assembly 123 facing the first drive coil assembly 120 is disposed vertically above the optical axis A.

  The first drive magnet assembly 123 is composed of six drive magnets 123a, 123b, 123c, 123d, 123e, 123f arranged adjacent to each other. Similarly, the second drive magnet assembly 124 and the third drive magnet assembly 125 are also composed of six drive magnets. Also, since the first to third drive magnet assemblies have the same configuration except for the direction in which they are arranged on the fixed plate, the configuration of the first drive magnet assembly 123 will be mainly described below.

  The six drive magnets 123a to 123f constituting the first drive magnet assembly 123 are each formed in a rectangular plate shape. These drive magnets 123a to 123f are arranged three by three symmetrically on both sides of the symmetry axis directed in the radial direction of the circle C centering on the optical axis A, and the long sides of each drive magnet are the symmetry axis And each are oriented to be parallel.

  Furthermore, the center points of the four drive magnets 123b to 123e arranged at the center of the first drive magnet assembly 123 are located on the center tangent T in contact with the circle C centered on the optical axis A. . On the other hand, the center points of the two drive magnets 123a and 123f disposed at both ends of the first drive magnet assembly 123 are located closer to the optical axis A with respect to the center tangent T. ing.

  Further, each drive magnet constituting the first drive magnet assembly 123 is magnetized so as to have different magnetic poles on the front and back surfaces. In the present embodiment, the six drive magnets 123a to 123f have the surface (surface facing the drive coil assembly) in the order of N pole, S pole, N pole, S pole, N pole, S pole. It is magnetized by

  Furthermore, as shown by an imaginary line in FIG. 6, the drive magnet 123 b constituting the first drive magnet assembly 123 is one side (side) of the center coil 120 a constituting the first drive coil assembly 120, and It is arrange | positioned so as to oppose one side (side) of the side coil 120c adjacent to this. Similarly, the drive magnet 123e is disposed to face one side (side) of the center coil 120b and one side (side) of the side coil 120d adjacent thereto. On the other hand, the drive magnet 123c disposed at the center of the first drive magnet assembly 123 faces only one side (side) of the center coil 120a, and the drive magnet 123d is one side (side) of the center coil 120b. ) And only facing. Furthermore, the drive magnet 123a disposed at the end of the first drive magnet assembly 123 faces only one side (side) of the side coil 120c, and the drive magnet 123f is one side (side) of the side coil 120d. ) And only facing.

  Further, the first drive coil assembly 120 is configured such that current in the same direction always flows through one side (side) of each coil and one side (side) of a coil adjacent thereto.

  In the first drive coil assembly 120, current flows in such a direction, and the magnetic poles of the respective drive magnets of the first drive magnet assembly 123 opposed thereto are oriented as described above. Thus, when current is supplied to the first drive coil assembly 120, a drive force in a direction parallel to the central tangent T is generated between the first drive coil assembly 120 and the first drive magnet assembly 123. Do. Similarly, between the second drive coil assembly 121 and the second drive magnet assembly 124, and also between the third drive coil assembly 122 and the first drive magnet assembly 125, a direction parallel to the respective center tangent T. Driving force is generated.

<Effect of actuator>
According to the actuator 100 in the present embodiment, it has three drive coil assemblies 120, 121, 122 arranged around the optical axis A, and each drive coil assembly 120, 121, 122 is adjacent to each other. The two center coils 121a and 121b and the side coils 121c and 121d are arranged side by side (FIG. 6). For this reason, a large driving force can be generated between the drive coil assemblies 120, 121, 122 and the drive magnet assemblies 123, 124, 125 disposed opposite to each other. Also, among the coils of the drive coil assembly 120, the side coil 120c disposed on opposite ends, the center point S _13, S ₁₄ of 120d, each center coil 120a, the center point S _11, S ₁₂ of 120b It is located on the side closer to the optical axis A with respect to the central tangent T passing through. For this reason, in the actuator 10 of the present embodiment, many coils can be disposed without waste in a limited space around the image shake correcting lens 116, and a large size can be obtained without increasing the outer diameter of the lens barrel. Driving force can be obtained.

<Modification>
Further, in the above-described embodiment of the present invention, the actuator is provided with three drive coil assemblies and three drive magnet assemblies around the image blur correction lens, but as a modification example More than one can be provided. In the modification shown in FIG. 7, four drive coil assemblies 220, 221, 222, 223 are arranged around the image blur correction lens 216 attached to the moving frame of the actuator. Further, as shown by imaginary lines in FIG. 7, four drive magnet assemblies 224, 225, 226, 227 are disposed on the fixed plate of the actuator so as to face each drive coil assembly. According to this modification, since the drive coil and the drive magnet can be efficiently arranged in a narrow space around the image blur correction lens 216, the drive coil assembly and the actuator without increasing the size of the actuator The number of drive magnet assemblies can be increased, and a large drive force can be obtained.

Third Embodiment
Next, a camera according to a third embodiment of the present invention will be described with reference to FIG. The camera of this embodiment differs from the first embodiment in the configuration of the built-in actuator. Therefore, only the points of the present embodiment different from the first embodiment will be described here, and the description of the same configuration, operation, and effects will be omitted.

<Structure of Actuator>
FIG. 8 is a front view of a moving frame of an actuator provided in a camera according to a third embodiment of the present invention. As shown in FIG. 8, the actuator 300 in the present embodiment is provided with three drive coil assemblies and three drive magnet assemblies.

  That is, the actuator 300 includes a moving frame 314 which is a movable portion, an image blur correction lens 316 attached thereto, a first drive coil assembly 320, a second drive coil assembly 321, and a third drive coil. It has an assembly 322. Furthermore, as shown by an imaginary line in FIG. 8, a first drive magnet assembly 323, which is disposed on the fixed plate (not shown) of the actuator 300 so as to face the first to third drive coil assemblies, A second drive magnet assembly 324 and a third drive magnet assembly 325 are provided.

  First, as shown in FIG. 8, the first, second, and third drive coil assemblies 320, 321, 322 are equally spaced on the circumference of a circle centered on the optical axis A, and the first drive The coil assembly 320 is disposed vertically above the optical axis A.

  The first, second, and third drive coil assemblies 320, 321, 322 are each composed of four adjacently arranged coils. That is, the first drive coil assembly 320 includes two center coils 320a and 320b, which are coils disposed at the central portion thereof, and two side coils 320c and 320d, which are disposed adjacent to both of them. It is done. Similarly, the second drive coil assembly 321 includes two center coils 321a and 321b and two side coils 321c and 321d, and the third drive coil assembly 322 includes two center coils 322a and 322b and two It comprises side coils 322c and 322d. The two center coils and the side coils on both sides thereof have the same configuration. Also, the first to third drive coil assemblies have the same configuration except for the direction in which they are disposed on the moving frame 314.

  Further, the configuration and arrangement of the first to third drive coil assemblies are the same as the configuration and arrangement of the first to third drive coil assemblies in the above-described second embodiment, and thus the description thereof will be omitted.

  Furthermore, magnetic sensors 326a and 326b are respectively disposed inside the two center coils 320a and 320b of the first drive coil assembly 320. Similarly, magnetic sensors are respectively disposed inside the two center coils of the second and third drive coil assemblies.

  On the other hand, first, second and third drive magnet assemblies 323, 324 and 325 shown in phantom in FIG. 8 are embedded in the fixed plate (not shown). The first, second and third drive magnet assemblies 323, 324 and 325 are arranged on the circumference of a circle C centered on the optical axis A so as to face the first to third drive coil assemblies respectively. The central angles are spaced at equal intervals of 120 °. In the present embodiment, the first drive magnet assembly 323 facing the first drive coil assembly 320 is disposed vertically above the optical axis A.

  The first drive magnet assembly 323 is composed of five drive magnets 323a, 323b, 323c, 323d, and 323e arranged adjacent to each other. Similarly, the second drive magnet assembly 324 and the third drive magnet assembly 325 are also composed of five drive magnets. Also, since the first to third drive magnet assemblies have the same configuration except for the direction in which they are arranged on the fixed plate, the configuration of the first drive magnet assembly 323 will be mainly described below.

  The five drive magnets 323a to 323e constituting the first drive magnet assembly 323 are each formed in a rectangular plate shape. Of these drive magnets, the drive magnet 323c disposed at the center is wider than the other drive magnets and is formed in a horizontally long rectangular shape, and its central axis is centered on the optical axis A. It is oriented in the radial direction of the circle C. Further, the other four drive magnets are formed in a vertically long rectangular shape, and are arranged adjacent to each other on the both sides of the central drive magnet 323c such that the long sides thereof are parallel to each other.

  Furthermore, the center points of the three drive magnets 323b to 323d disposed at the center of the first drive magnet assembly 323 are located on the center tangent T in contact with the circle C centered on the optical axis A. . On the other hand, center points of the two drive magnets 323a and 323e disposed at both ends of the first drive magnet assembly 323 are located closer to the optical axis A with respect to the center tangent T. ing.

  In addition, each drive magnet constituting the first drive magnet assembly 323 is magnetized so as to have different magnetic poles on the front and back surfaces. In the present embodiment, the five drive magnets 323a to 323e are magnetized such that the surfaces (surfaces facing the drive coil assembly) are sequentially N pole, S pole, N pole, S pole and N pole. It is done.

  Furthermore, as shown by an imaginary line in FIG. 8, the drive magnet 323 b constituting the first drive magnet assembly 323 is one side (side) of the center coil 320 a constituting the first drive coil assembly 320, and It is arrange | positioned so as to oppose one side (side) of the side coil 320c adjacent to this. Similarly, the drive magnet 323 d is disposed to face one side (side) of the center coil 320 b and one side (side) of the side coil 320 d adjacent thereto. On the other hand, the drive magnet 323c disposed at the center of the first drive magnet assembly 323 faces the center side (side) of the center coil 320a and the center side (side) of the center coil 320b. Furthermore, the drive magnet 323a disposed at the end of the first drive magnet assembly 323 faces only one side (side) of the side coil 320c, and the drive magnet 323e is one side (side) of the side coil 320d. ) And only facing.

As described above, in the present embodiment, the drive magnet facing the inner side of the two center coils 320a and 320b is shared by one drive magnet 323c disposed at the center.
Further, the first drive coil assembly 320 is configured such that current in the same direction always flows through one side (side) of each coil and one side (side) of the coil adjacent thereto.

  In the first drive coil assembly 320, current flows in such a direction, and the magnetic poles of the drive magnets of the first drive magnet assembly 323 opposed thereto are oriented as described above. As a result, when a current is supplied to the first drive coil assembly 320, a drive force in a direction parallel to the central tangent T is generated between the first drive coil assembly 320 and the first drive magnet assembly 323. Do. Similarly, between the second drive coil assembly 321 and the second drive magnet assembly 324, and also between the third drive coil assembly 322 and the first drive magnet assembly 325, a direction parallel to the respective center tangent T. Driving force is generated.

  Further, the magnetic sensor 326a disposed inside the one center coil 320a detects the magnetism of the driving magnet 323b and the driving magnet 323c disposed on the opposite magnetic pole. Thus, the magnetic sensor 326a can detect the amount of movement of the first drive coil assembly 320 relative to the first drive magnet assembly 325 in the direction parallel to the center tangent T. Similarly, the magnetic sensor 326b disposed inside the center coil 320b detects the magnetism of the drive magnet 323c and the drive magnet 323d disposed on the opposite magnetic pole, and a direction parallel to the center tangent T The amount of movement of the first drive coil assembly 320 can be detected.

<Effect of actuator>
According to the actuator 300 in the present embodiment, it has three drive coil assemblies 320, 321, 322 arranged around the optical axis A, and each drive coil assembly 320, 321, 322 is adjacent to each other. It consists of two center coils 321a and 321b and side coils 321c and 321d arranged side by side (FIG. 8). Therefore, a large driving force can be generated between the drive coil assemblies 320, 321, 322 and the drive magnet assemblies 323, 324, 325 disposed opposite to each other. Further, among the coils of the drive coil assembly 320, center points of the side coils 320c and 320d disposed at both ends are light with respect to a center tangent T passing through each center point of the center coils 320a and 320b. It is located closer to the axis A. For this reason, in the actuator 300 according to the present embodiment, many coils can be disposed without waste in a limited space around the image blur correction lens 316, and a large size can be obtained without increasing the outer diameter of the lens barrel. Driving force can be obtained.

<Modification>
In the third embodiment of the present invention described above, one magnetic sensor is disposed inside each of the two center coils of each drive coil assembly, but as a modification, between the two center coils The present invention can also be configured to detect the position of the moving frame by disposing two magnetic sensors at. Furthermore, as another modification, the present invention can be configured to detect the position of the moving frame by arranging one magnetic sensor only in one of the two center coils of each drive coil assembly. .

  Although the preferred embodiments of the present invention have been described above, various modifications can be added to the above-described embodiments. In particular, although the drive coil assembly is composed of three or four coils in the embodiment described above, the drive coil assembly can be composed of three or more arbitrary number of coils. In the embodiment described above, the drive coil is attached to the movable portion side and the drive magnet is attached to the fixed portion side. However, the drive magnet assembly is attached to the movable portion side, and the drive coil is attached to the fixed portion side. The present invention can also be applied to actuators of the type having an assembly attached.

Reference Signs List 1 camera 2 lens unit 4 camera body 4a image pickup element surface 6 lens barrel 8 lens 10 actuator 12 fixing plate (fixing portion)
14 Moving frame (movable part)
16 Image Stabilizing Lens 18 Steel Ball (Moving Part Support Means)
20 first drive coil assembly 20a center coil 20b, 20c side coil 21 second drive coil assembly 21a center coil 21b, 21c side coil 22 third drive coil assembly 22a center coil 22b, 22c side coil 23 for first drive Magnet assembly 23a, 23b, 23c, 23d Drive magnet 24 Second drive magnet assembly 24a, 24b, 24c, 24d Drive magnet 25 Third drive magnet assembly 25a, 25b, 25c, 25d Drive magnet 26a First magnetic Sensor 26b Second magnetic sensor 26c Third magnetic sensor 32 Back yoke 33 Closed magnetic yoke 34 Gyro 36 Controller 100 Actuator 114 Moving frame (movable part)
116 Image blur correction lens 120 First drive coil assembly 120a, 120b Center coil 120c, 120d Side coil 121 Second drive coil assembly 121a, 121b Center coil 121c, 121d Side coil 122 Third drive coil assembly 122a, 122b Center coil 122c, 122d side coil 123 first drive magnet assembly 123a, 123b, 123c, 123d, 123e, 123f drive magnet 124 second drive magnet assembly 125 third drive magnet assembly 216 image blur correction lens 220, 221, 222, 223 Drive coil assemblies 224, 225, 226, 227 Drive magnet assemblies 300 Actuators 314 Moving frame (movable part)
316 image blur correction lens 320 first drive coil assembly 320a, 320b center coil 320c, 320d side coil 321 second drive coil assembly 322 third drive coil assembly 323 first drive magnet assembly 323a, 323b, 323c, 323d, 323e driving magnet 324 second driving magnet assembly 325 third driving magnet assembly 326a, 326b magnetic sensor

Claims (10)

An actuator for moving an image blur correction lens in a plane orthogonal to the optical axis to correct the image blur,
Fixed part,
A movable portion to which the image blur correction lens is attached;
A movable portion supporting means for supporting the movable portion so as to be movable relative to the fixed portion on a plane orthogonal to the optical axis of the image blur correction lens;
Three or more drive coil assemblies disposed around the optical axis on either the fixed part or the movable part;
Three or more drive magnet assemblies provided on the other of the fixed part or the movable part so as to face each of the drive coil assemblies and generate drive force with each of the drive coil assemblies. And
Each of the drive coil assemblies is composed of three or more adjacently arranged coils, and among these coils, the center points of the coils disposed at both ends are disposed at the central portion. An actuator characterized in that it is located closer to the optical axis with respect to a central tangent line which passes through the center point of the coil and which is a straight line contacting a circle centered on the optical axis.   Among the coils constituting each of the drive coil assemblies, the coils disposed at the end portions on both sides are formed so that the width in the direction perpendicular to the central tangent line is narrower than the coils disposed at the central portion. The actuator according to item 1.   Each of the coils constituting each of the drive coil assemblies is formed in a substantially rectangular shape, and among these coils, the coil disposed at the center portion has a length in a direction perpendicular to the center tangent line as the center tangent direction. The actuator according to claim 1 or 2, wherein an aspect ratio, which is a value divided by a length, is formed larger than an aspect ratio of a coil disposed at both ends.   Among the coils constituting each of the drive coil assemblies, the coils disposed at the end portions on both sides have a larger number of turns of the conducting wire than the coils disposed at the central portion. The actuator according to any one of the above.   5. The coil according to any one of claims 1 to 4, wherein the inner diameter of the coil disposed at each end of the coils constituting the drive coil assembly is smaller than the inner diameter of the coil disposed at the center. The actuator according to item 1.   The magnetic sensor further includes a magnetic sensor that detects the magnetism of the drive magnet assembly to detect the amount of movement of the movable portion with respect to the fixed portion, and the magnetic sensor includes coils among the coils constituting the drive coil assemblies. The actuator according to any one of claims 1 to 5, wherein the actuator is disposed inside a coil disposed in a central portion.   The drive coil assembly and the drive magnet assembly disposed opposite to the drive coil assembly are each configured to generate a drive force in a direction parallel to the central tangent line. The actuator according to item 1 or 2.   Each of the drive coil assemblies is composed of three coils, and each of the drive magnet assemblies is composed of a plurality of magnets, and one drive magnet constituting the drive magnet assembly is one of the three coils. The actuator according to any one of claims 1 to 7, which is disposed to face one side of a coil disposed at the center thereof and one side of a coil adjacent thereto. A lens unit with an image shake correction function,
A lens barrel,
A lens housed inside the lens barrel;
The actuator according to any one of claims 1 to 8, wherein the image blur correction lens is moved in a plane orthogonal to the optical axis of the lens.
A lens unit characterized by having. A camera with an image shake correction function,
Camera body,
A lens unit according to claim 9;
A camera characterized by having:

Images