JP2013045068A - Vibration-proof actuator, lens unit with the same, and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration-proof actuator able to restrict significant disturbance of an image when an image blur prevention lens is locked or the lens is returned from a locked state.SOLUTION: The vibration-proof actuator according to the present invention comprises: a stationary part (12); a movable part (14) to which the image blur prevention lens (16) is attached and which has at least three locking contact parts (14b) provided around the image blur prevention lens; movable-part support means (18) for movably supporting the movable part; drive means (20, 22) for driving the movable part; and at least three locking arms (42) rotatably arranged around the image blur prevention lens so as to counter each locking contact part. When the locking arms are rotated to arm locking positions, the respective arm contact parts (42d) of the locking arms are brought into contact with the corresponding locking contact parts. Consequently, the translational position and rotational position of the movable part are locked to predetermined movable-part locking positions.

Description

  The present invention relates to an anti-vibration actuator, and more particularly, to an anti-vibration actuator disposed inside a lens barrel for moving an image blur prevention lens, a lens unit including the same, and a camera.

  Japanese Patent Laid-Open No. 10-260445 (Patent Document 1) describes a “shake correction device”. This shake correction apparatus includes a fixing unit that locks an image blur prevention lens for preventing image blur. In this shake correction apparatus, when image blur correction is not performed, the fixing unit is engaged with the lens frame of the image blur prevention lens, and the image blur prevention lens is locked at a predetermined position. The fixing means is a ring-shaped member disposed so as to surround the lens frame of the image blur prevention lens, and is rotated when the lens frame is locked, and is provided on the inner peripheral surface of the fixing means and the lens frame. The lens frame is locked by engaging the protrusion.

Japanese Patent Laid-Open No. 10-260445

  However, in the shake correction apparatus disclosed in Japanese Patent Laid-Open No. 10-260445, when the image blur prevention lens is locked, the inner peripheral surface of the ring-shaped fixing unit is in contact with the projection of the lens frame while rotating, and the lens frame Is finally locked at a predetermined locking position. That is, at the time of locking, a rotational force that rotates the lens frame acts on the lens frame together with a force for translating the lens frame to a predetermined locking position. For this reason, when the image blur prevention lens is locked, the lens is rotated while being translated, so that the image formed on the viewfinder is greatly disturbed, and there is a problem that the camera user is uncomfortable. Further, when the lens frame is returned from the locked state to the non-locked state, the fixing means engaged with the projection of the lens frame is rotated in the reverse direction, so that the image blur prevention lens moves in translation. At the same time, the image formed on the viewfinder is greatly disturbed.

  Further, in the shake correction apparatus described in Japanese Patent Laid-Open No. 10-260445, the lens frame of the image shake prevention lens is elastically constrained by two coil springs, so that the ring-shaped fixing means is rotated. Thus, the lens frame and the fixing means can be reliably engaged and locked. However, in an image shake correction apparatus of a type in which the lens frame is supported by rolling with a ball bearing or the like, and the rotational movement of the lens frame is not mechanically restricted during image shake correction, the lens frame is also rotated with the rotation of the fixing means. End up. For this reason, the locking mechanism described in Japanese Patent Laid-Open No. 10-260445 has a problem that it cannot be applied to a type of image blur correction device in which the rotational movement of the lens frame is not mechanically restricted.

  Accordingly, the present invention provides an anti-vibration actuator capable of suppressing the image from being largely disturbed when the image blur prevention lens is locked or when returning from the locked state, and a lens unit and a camera including the same. It is intended to provide.

  In order to solve the above-described problems, the present invention provides a vibration-proof actuator disposed inside a lens barrel for moving an image-shake prevention lens, and includes a fixing unit and an image-shake prevention lens. A movable part provided with at least three locking contact parts mounted around the image blur prevention lens and movable part support means for supporting the movable part movably with respect to the fixed part Driving means between the fixed portion and the movable portion to drive the movable portion relative to the fixed portion, and the periphery of the image blur prevention lens so as to face each locking contact portion And at least three locking arms that are pivotably disposed on each other, and when these locking arms are rotated to the arm locking position, the arm contact portion of each locking arm is The abutting parts for locking are in contact with each other, and the translational position and rotational position of the movable part are set. It is characterized in that locking the movable part locking the position of the constant.

  In the present invention configured as described above, the movable portion to which the image blur prevention lens is attached is supported by the movable portion support means so as to be movable with respect to the fixed portion. The driving means drives the movable part by applying a driving force between the fixed part and the movable part. Further, the movable portion is provided with at least three locking contact portions, and at least three locking arms are rotated around the image blur prevention lens so as to face each locking contact portion. It is arranged to be movable. When the locking arm is rotated to the arm locking position, the arm contact portion of each locking arm is brought into contact with the locking contact portion, and the translation position and the rotation position of the movable portion are predetermined. It is locked at the movable portion locking position.

  According to the present invention configured as described above, the translation position and the rotation position of the movable portion are locked to the predetermined movable portion locking position by the locking arm. The image is greatly disturbed at the time of release, and the user is not uncomfortable. Further, according to the present invention configured as described above, the movable portion is locked by at least three locking arms arranged around the image blur prevention lens, so that the rotational movement is mechanically restricted. Unmovable movable parts can also be locked.

In the present invention, preferably, each locking contact portion and each arm contact portion are in contact with each other with a predetermined contact area when the movable portion is positioned at the movable portion locking position.
According to the present invention configured as described above, the contact portions for locking and the arm contact portions come into contact with each other with a predetermined contact area, so that the surface pressure acting on each contact portion can be reduced. The wear of the contact portion can be suppressed.

In the present invention, preferably, each of the locking contact portions and each of the arm contact portions includes a plane portion, and when the movable portion is positioned at the movable portion locking position, The flat portion and the flat portion of each arm contact portion are in surface contact with each other.
According to the present invention configured as described above, the contact surface of each contact portion is formed by the flat surface portion, so that a contact surface having a wide contact area can be easily formed.

In the present invention, preferably, each locking contact portion and each arm contact portion are in point contact at a plurality of points or in a plurality of linear regions when the movable portion is positioned at the movable portion locking position. Line contact.
According to the present invention configured as described above, each contact portion is brought into point contact or surface contact, so that a dimensional error or the like of the locking contact portion and the arm contact portion is absorbed by elastic deformation of the contact portion. It is possible to contact each contact portion with certainty.

In the present invention, preferably, the movable portion includes a peripheral wall portion formed so as to surround the image blur prevention lens, and each locking contact portion is formed by cutting out the peripheral wall portion. .
According to the present invention configured as described above, each locking contact portion is formed on the peripheral wall portion formed so as to surround the image blur prevention lens. The structure which latches from the circumference | surroundings by the arm for use can be obtained easily.

  In the present invention, preferably, each locking contact portion is centered on the optical axis of the image blur prevention lens, and a radius of a circle passing through each contact portion between each locking contact portion and each arm contact portion. It is comprised by the curved surface with a larger curvature radius than.

  According to the present invention configured as described above, each locking contact portion can be configured by a curved surface having a predetermined radius of curvature, so that the locking contact portion is formed by a curved surface similar to a cylindrical surface. This makes it possible to easily form the locking contact portion.

In addition, the present invention is a lens unit including an anti-vibration actuator, and includes a lens barrel, an imaging lens disposed inside the lens barrel, and the anti-vibration actuator of the present invention. It is a feature.
Furthermore, the present invention is a camera provided with an anti-vibration actuator, and includes a camera body and the lens unit of the present invention.

According to the vibration-proof actuator of the present invention, and the lens unit and camera including the same, it is possible to suppress the image from being greatly disturbed when the image-shake prevention lens is locked or when returning from the locked state. .
The present invention can also be applied to an anti-vibration actuator of a type in which the rotational movement of the movable part is not mechanically restricted.

It is sectional drawing of the camera by embodiment of this invention. It is side surface sectional drawing of the vibration proof actuator with which the camera of embodiment of this invention was equipped. It is a front view which shows the movable part of a vibration proof actuator. It is a front view of the fixed part which removes and shows the movable part of a vibration proof actuator. It is a disassembled perspective view of a vibration proof actuator. It is a perspective view which shows the arm for a latching of a movable part, and the arm drive plate which drives this. It is a figure which shows typically the latching mechanism of a vibration proof actuator. It is a figure which shows typically the latching mechanism of the vibration proof actuator by the modification of this invention. It is a figure which shows typically the latching mechanism of the vibration proof actuator by the modification of this invention.

Next, embodiments of the present invention will 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. FIG. 1 is a cross-sectional view of a camera according to an embodiment of the present invention.
As shown in FIG. 1, a camera 1 according to an 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 imaging lenses 8 disposed in the lens barrel, an image stabilization actuator 10 that moves the image blur prevention lens 16 within a predetermined plane, and a lens. And a gyro 34 which is a vibration detecting means for detecting the vibration of the lens barrel 6.

  In the camera 1 according to the embodiment of the present invention, the vibration is detected by the gyro 34, and the image stabilization actuator 10 is operated based on the detected vibration to move the image stabilization lens 16. The image focused on C is stabilized. In the present embodiment, a piezoelectric vibration gyro is used as the gyro 34. In the present embodiment, the image blur prevention lens 16 is constituted by a single lens, but the lens for stabilizing the image may be a plurality of lens groups. In this specification, the image blur prevention lens includes one lens and a lens group for stabilizing an image.

The lens unit 2 is attached to the camera body 4 and configured to form incident light on the image sensor C.
The generally cylindrical lens barrel 6 holds a plurality of imaging lenses 8 therein, and allows focus adjustment by moving some imaging lenses 8.

  Next, the vibration-proof actuator 10 will be described with reference to FIGS. FIG. 2 is a side cross-sectional view of the vibration isolation actuator provided in the camera of the embodiment of the present invention. FIG. 3 is a front view showing a movable part of the vibration-proof actuator 10, and FIG. 4 is a front view of a fixed part with the movable part of the vibration-proof actuator 10 removed. 2 is a cross-sectional view showing a state in which the vibration-proof actuator 10 is broken along the line II-II in FIG. FIG. 5 is an exploded perspective view of the vibration-proof actuator 10. FIG. 6 is a perspective view showing a locking arm of the movable part and an arm driving plate for driving the arm. FIG. 7 is a diagram schematically showing a locking mechanism of the vibration-proof actuator 10.

  As shown in FIGS. 2 to 5, the anti-vibration actuator 10 is supported by a fixed plate 12 that is a fixed portion fixed in the lens barrel 6, and can be translated and rotated with respect to the fixed plate 12. A movable frame 14 that is a movable portion, and three steel balls 18 that are movable portion support means for supporting the movable frame 14. Further, the vibration isolation actuator 10 includes a first drive coil 20a, a second drive coil 20b, a third drive coil 20c attached to the fixed plate 12, and each drive coil 20a, 20b of the moving frame 14. , 20c, and the first driving magnet 22a, the second driving magnet 22b, and the third driving magnet 22c, which are attached to the positions corresponding to the respective driving coils 20a, 20b, and 20c. It has the 1st magnetic sensor 24a which is a 1st, 2nd, 3rd position detection element, the 2nd magnetic sensor 24b, and the 3rd magnetic sensor 24c.

  Further, the vibration isolation actuator 10 includes a suction yoke 26 attached to the back side of the fixed plate 12 in order to cause the moving frame 14 to be attracted to the fixed plate 12 by the magnetic force of each driving magnet. The first driving coil 20a, the second driving coil 20b, the third driving coil 20c, and the first driving magnet 22a, the second driving magnet 22b, and the third driving coil, which are respectively attached to the corresponding positions. The drive magnet 22c constitutes first, second, and third drive means for driving the moving frame 14 with respect to the fixed plate 12, respectively.

  Further, as shown in FIG. 1, the vibration isolation actuator 10 detects vibration detected by the gyro 34 and positional information of the moving frame 14 detected by the first, second, and third magnetic sensors 24 a, 24 b, and 24 c. Based on the controller 36, the controller 36 is a control unit that controls the current flowing through the first, second, and third drive coils 20a, 20b, and 20c.

  The anti-vibration actuator 10 translates the moving frame 14 relative to the fixed plate 12 fixed to the lens barrel 6 in a plane parallel to the image sensor surface C, and thereby the image blur attached to the moving frame 14. Even if the prevention lens 16 is moved and the lens barrel 6 vibrates, it is driven so that the image formed on the image sensor surface C is not disturbed.

  As shown in FIGS. 2 and 3, the moving frame 14 has a generally donut plate shape, and an image blur prevention lens 16 is attached to the central opening. A cylindrical peripheral wall portion 14 a is formed around the central opening of the moving frame 14 so as to surround the image blur prevention lens 16. At four locations on the outer peripheral surface of the peripheral wall portion 14a, locking contact portions 14b formed by cutting out the peripheral wall portion 14a are formed. The locking contact portions 14b are recessed portions formed at equal intervals on the outer peripheral surface of the peripheral wall portion 14a. Details of the locking contact portion 14b will be described later.

  Furthermore, first, second, and third driving magnets 22a, 22b, and 22c are disposed on the moving frame 14. As shown in FIG. 3, the centers of these three drive magnets are respectively arranged on the circumference of a circle centered on the optical axis of the lens unit 2. In the present embodiment, the second drive magnet 22b is disposed vertically below the optical axis, and the first drive magnet 22a, the second drive magnet 22b, and the third drive magnet 22c are equally spaced at a central angle. They are spaced about 120 ° apart.

  The first, second, and third driving magnets 22a, 22b, and 22c are substantially rectangular, and the center line that crosses the long sides of the first, second, and third driving magnets 22a, 22b, and 22c is directed in the radial direction of a circle centered on the optical axis of the lens unit 2. Are arranged to be. The first, second, and third driving magnets 22a, 22b, and 22c are magnetized so that the center line that crosses the long side becomes the magnetization boundary line.

  As shown in FIGS. 2 and 4, the fixed plate 12 is a generally donut-shaped disk and is located on the circumference at positions corresponding to the first, second, and third drive magnets 22 a, 22 b, and 22 c. Are provided with first, second, and third drive coils 20a, 20b, and 20c, respectively. The first, second, and third drive coils 20a, 20b, and 20c are wound in a generally rectangular shape with rounded corners, and one of the center lines is centered on the optical axis. It is arranged toward the tangential direction of the circumference.

  As shown in FIGS. 2 and 3, the three steel balls 18 are sandwiched between the fixed frame 12 and the moving frame 14, and each have a central angle of 120 ° on the circumference of a circle centered on the optical axis A. They are arranged at intervals. The fixed frame 12 has a recess 30 at a position corresponding to each steel ball 18. Further, the moving frame 14 is formed with a recess 31 at a position corresponding to each steel ball 18. Each steel ball 18 is arrange | positioned in these recessed parts 30 and 31, and omission is prevented. As will be described later, since the moving frame 14 is attracted to the fixed plate 12 by the driving magnet, each steel ball 18 is sandwiched between the fixed plate 12 and the moving frame 14. As a result, the moving frame 14 is supported on a plane parallel to the fixed plate 12, and each steel ball 18 is rolled while being held, so that translational movement and rotational movement of the moving frame 14 with respect to the fixed plate 12 are allowed. Is done.

  As shown in FIG. 2, the suction yoke 26 has a substantially rectangular plate shape, and is attached to the back side of each driving coil of the fixed plate 12. The moving frame 14 is attracted to the fixed plate 12 by the magnetic force exerted on each attracting yoke 26 by each driving magnet.

  The first, second, and third driving magnets 22a, 22b, and 22c apply magnetism to the rectangular first and second third driving coils 20a, 20b, and 20c. Thus, when a current flows through each driving coil, a circumferential driving force is generated between each corresponding driving magnet.

  As shown in FIGS. 2 and 4, a first magnetic sensor 24a, a second magnetic sensor 24b, and a third magnetic sensor 24c are arranged inside each driving coil, respectively, and the circumference of each driving coil is arranged. It is configured to measure directional displacement. Based on the signals detected by the first, second, and third magnetic sensors 24a, 24b, and 24c, the position where the moving frame 14 is translated and rotated with respect to the fixed frame 12 can be specified. In the present embodiment, a Hall element is used as the magnetic sensor.

Next, with reference to FIGS. 5 to 7, the locking mechanism of the vibration isolation actuator 10 will be described.
As shown in FIGS. 5 to 7, the locking mechanism of the vibration-proof actuator 10 includes an arm support plate 40, four locking arms 42 rotatably attached to the arm support plate 40, and An arm drive plate 44 for driving the locking arm 42, a drive motor 46 for rotationally driving the arm drive plate 44, and a motor support plate 48 for supporting the drive motor 46. .

  The arm support plate 40 is a donut plate-like member fixed in the lens barrel 6. The arm support plate 40 is disposed so that the peripheral wall portion 14a of the moving frame 14 protrudes through the central opening. Further, the arm support plate 40 is formed with four arm bearings 40a disposed on a circumference centered on the optical axis A. These arm bearings 40a rotatably receive the arm shafts 42a of the respective locking arms 42, so that the four locking arms 42 are rotatably supported by the arm support plate 40.

  The locking arm 42 includes an elongated arm main body 42b extending in parallel with the arm support plate 40, an arm shaft 42a extending from one end of the arm main body 42b toward the arm support plate 40, and an arm main body 42b. The cam follower projection 42c extending in the direction opposite to the arm shaft 42a from the other end of the arm, and the arm contact portion 42d formed at the intermediate portion of the arm main body portion 42b.

  The arm shaft 42a is a columnar portion extending in the direction of the optical axis A from one end of the arm main body 42b toward the arm support plate 40, and is rotatably received by the arm bearing 40a of the arm support plate 40. It is done. Thus, the locking arm 42 is supported so as to be rotatable about the arm bearing 40a in a plane parallel to the arm support plate 40 (in a plane orthogonal to the optical axis A). On the other hand, since the peripheral wall 14a of the moving frame 14 formed so as to surround the image blur prevention lens 16 protrudes from the central opening of the arm support plate 40, the four locking arms 42 have the The lens is disposed around the shake preventing lens 16 and the peripheral wall portion 14a.

  The cam follower protrusion 42c is formed at the end of the arm main body 42b opposite to the arm shaft 42a, and extends from the arm main body 42b in the direction of the optical axis A and in the direction opposite to the arm shaft 42a. Part. The cam follower projection 42c is received in a cam groove 44a provided on the arm drive plate 44, and the locking arm 42 is rotated by moving the cam follower projection 42c along the cam groove 44a.

  The arm contact portion 42d is formed at an intermediate portion of the arm main body portion 42b. As shown in FIG. 7, the arm contact portion 42 d protrudes inward in the radial direction of a circle having the optical axis A as the center in a plane parallel to the arm support plate 40. The arm contact portion 42d is configured to contact the locking contact portion 14b provided on the moving frame 14 when the moving frame 14 is locked. The contact surface on which the arm contact portion 42d contacts the locking contact portion 14b is configured as a flat portion. Further, in a state where the arm contact portion 42d of each locking arm 42 is in contact with the locking contact portion 14b of the moving frame 14 and the moving frame 14 is locked at a predetermined movable portion locking position, The contact surface of the arm contact portion 42d is directed in a tangential direction of a circle with the optical axis A as the center.

  On the other hand, the locking contact portion 14b formed in the peripheral wall portion 14a of the moving frame 14 is a concave portion formed by providing a cutout in the peripheral wall portion 14a. The bottom surface of the concave portion is formed as a flat portion directed in the tangential direction of a circle with the optical axis A as the center. Accordingly, the contact surface of the arm contact portion 42d and the bottom surface of the locking contact portion 14b are both flat, and when the moving frame 14 is locked, the arm contact portion 42d and the locking contact portion 14b. Becomes surface contact with a predetermined contact area. For this reason, in a state where each locking contact portion 14b of the moving frame 14 and each locking contact portion 14b of the locking arm 42 are in contact with each other, the rotational movement of the moving frame 14 is also restrained. The translational position and the rotational position of 14 are positioned at predetermined movable part locking positions. In the state where the moving frame 14 is positioned at the movable portion locking position, the optical axis of the image blur prevention lens 16 attached to the moving frame 14 and the light of the other imaging lens 8 in the lens barrel 6. The axes are in agreement.

  In actual contact between members, the members always contact each other with a certain contact area, but in this specification, terms such as “contact with a predetermined contact area”, “surface contact” and the like are substantially It means a contact state that cannot be regarded as point contact or line contact.

  As shown in FIG. 6, the arm drive plate 44 is a donut plate-like member disposed in parallel with the arm support plate 40. The arm drive plate 44 is supported in the lens barrel 6 so as to be rotatable about the optical axis A. Four cam grooves 44 a are formed on the surface of the arm drive plate 44 that faces the arm support plate 40. Each cam groove 44a is configured to receive a cam follower protrusion 42c of each locking arm 42.

  Each cam groove 44a is an elongated groove extending in a substantially circumferential direction of a circle centered on the optical axis A, and one end portion of each cam groove 44a is inward in the radial direction of the circle centered on the optical axis A. And the other end is located radially outward. For this reason, when the arm driving plate 44 is rotated in a state where each cam groove 44a receives each cam follower projection 42c, each locking arm 42 is rotated around the arm shaft 42a. That is, when the cam follower projection 42c is received in the radially inward portion of the cam groove 44a, the cam follower projection 42c and the arm contact portion 42d are positioned inward in the radial direction, and the movable frame 14 is locked. Is done. Further, when the arm drive plate 44 is rotated and the cam follower projection 42c is received in a portion located radially outward of the cam groove 44a, the cam follower projection 42c and the arm contact portion 42d are moved radially outward. The movement frame 14 is unlocked.

  Further, serrated teeth 44 b are formed on a part of the outer periphery of the arm drive plate 44. The teeth 44 b mesh with a gear 46 a attached to the output shaft of the drive motor 46, whereby the arm drive plate 44 is rotationally driven by the drive motor 46.

  The motor support plate 48 is a donut plate-like member fixed in the lens barrel 6, and a gear 46 a attached to the output shaft of the drive motor 46 meshes with teeth 44 b provided on the arm drive plate 44. Further, the drive motor 46 is supported at a predetermined position.

  Next, the operation of the camera 1 according to the embodiment of the present invention will be described with reference to FIG. First, by turning on a start switch (not shown) for the camera shake prevention function of the camera 1, the vibration isolation actuator 10 provided in the lens unit 2 is operated. The gyro 34 attached to the lens unit 2 detects vibration in a predetermined frequency band every moment and outputs it to an arithmetic circuit (not shown) built in the controller 36. The gyro 34 outputs an angular velocity signal to the arithmetic circuit, and the arithmetic circuit integrates the input angular velocity signal with time to calculate a deflection angle, and adds a predetermined correction signal to this to generate a lens position command signal. To do. By moving the image blur prevention lens 16 momentarily to the position commanded by the lens position command signal output in time series by the arithmetic circuit, the image focused on the film surface F of the camera body 4 is stabilized. Is done.

  The controller 36 causes a current corresponding to the difference between the detection signal of each magnetic sensor and the lens position command signal in each direction to flow through each driving coil. When a current flows through each driving coil, a magnetic field proportional to the current is generated. Due to this magnetic field, the first, second, and third driving coils 20a, 20b, and 20c arranged corresponding to the first, second, and third driving magnets 22a, 22b, and 22c receive the driving force and move. The frame 14 is moved. When the moving frame 14 is moved by the driving force and each driving coil reaches the position specified by the lens position command signal, the driving force becomes zero. Further, when the moving frame 14 moves out of the position specified by the lens position command signal due to a disturbance or a change in the lens position command signal, a current is again supplied to each driving coil, and the moving frame 14 Returns to the position specified by the signal.

  By repeating the above operation every moment, the image blur prevention 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 image sensor surface C of the camera body 4 is stabilized.

  Next, when the start switch (not shown) for the camera shake prevention function of the camera 1 is turned off, the controller 36 positions and locks the moving frame 14 at the movable portion locking position. That is, the controller 36 sends a signal to the drive motor 46 to rotate the gear 46a. When the gear 46a is rotated, the arm drive plate 44 is rotated clockwise in FIG. When the arm drive plate 44 is rotated clockwise, the cam follower protrusion 42c received in the radially outer portion of the cam groove 44a is received in the radially inner portion of the cam groove 44a. As a result, the locking arm 42 is rotated to the arm locking position, and the cam follower protrusion 42c and the arm contact portion 42d are moved inward in the radial direction. When the arm contact portion 42d is moved inward in the radial direction, as shown in FIG. 7, each arm contact portion 42d is brought into contact with the opposing locking contact portion 14b, and the moving frame 14 is engaged. Stopped.

  Here, in a state in which the moving frame 14 is locked, the locking contact portions 14b facing the arm contact portions 42d are in surface contact with each other, so that in addition to the translational movement of the moving frame 14, the moving frame 14 The rotational movement of is also constrained. In other words, in the locked state, the moving frame 14 is positioned at the reference rotation position while the optical axis of the image blur prevention lens 16 coincides with the optical axis of the other imaging lens 8. The reference rotation position refers to the first, second, and third drive coils 20a attached to the fixed plate 12 in a state where the optical axis of the image blur prevention lens 16 coincides with the optical axis of the other imaging lens 8. , 20b, 20c and the central axes of the first, second, and third driving magnets 22a, 22b, 22c attached to the moving frame 14 overlap. At the time of image blur prevention control, the moving frame 14 is translated while substantially maintaining this reference rotational position, and the image blur is corrected.

  Note that the locking contact portion 14b is not formed on the peripheral wall portion 14a of the moving frame 14, and the arm contact portion 42d of the locking arm 42 is in contact with the cylindrical surface on the outer periphery of the peripheral wall portion 14a. In such a case, even when the moving frame 14 is locked, the rotational movement of the moving frame 14 is not restricted, and the moving frame 14 is displaced from the reference rotation position. In the vibration isolating actuator 10 of the present embodiment, the translation position and the rotation position of the moving frame 14 are restrained to a predetermined movable portion locking position at the time of locking, so that the moving frame 14 is rotated and moved in the locking state. There is no end.

  Next, when a start switch (not shown) for the camera shake prevention function of the camera 1 is turned ON, the controller 36 sends a signal to the drive motor 46, rotates the gear 46a, and moves the arm drive plate 44 in FIG. Rotate counterclockwise at. When the arm drive plate 44 is rotated counterclockwise, the cam follower protrusion 42c received in the radially inner portion of the cam groove 44a is received in the radially outer portion of the cam groove 44a. Thus, the locking arm 42 is rotated, and the cam follower protrusion 42c and the arm contact portion 42d are moved outward in the radial direction. When the arm contact portion 42d is moved outward in the radial direction, each arm contact portion 42d is separated from the opposing locking contact portion 14b, and the locking of the moving frame 14 is released.

  At this time, the rotational position of the moving frame 14 is maintained at the reference rotational position even during locking, so that when the image blur prevention control is started after the locking is released, the moving frame 14 receives the lens position command signal. It is merely translated to the position specified by, and no rotational movement occurs simultaneously with the translation. For this reason, the image stabilization actuator 10 can smoothly shift from the locked state to the image blur prevention control state, and the image is not greatly disturbed during the transition to the image blur prevention control.

  According to the vibration-proof actuator 10 of the embodiment of the present invention, the translation position and the rotation position of the moving frame 14 are locked to the predetermined movable part locking position by the locking arm 42, so that the moving frame 14 is locked. The image is greatly distorted when the lock is released and the user is not discomforted. Further, according to the vibration-proof actuator 10 of the present embodiment, the moving frame 14 is locked by the four locking arms 42 arranged around the image blur-preventing lens 16, so that the rotational movement is mechanical. The moving frame can be locked even with a type of vibration-proof actuator that is not constrained by.

  Further, according to the vibration-proof actuator 10 of the present embodiment, the contact surfaces of the locking contact portion 14b and the arm contact portion 42d are configured by flat portions, so that a contact surface having a large contact area can be easily formed. Can be formed.

  Further, since each locking contact portion 14b is formed on the peripheral wall portion 14a formed so as to surround the image blur prevention lens 16, each locking arm 42 is disposed outside the moving frame 14. Therefore, a configuration in which the image blur prevention lens 16 is locked from the periphery by the locking arm 42 can be configured in a compact manner.

  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 present invention is applied to a digital camera. However, the present invention can be applied to any camera for capturing still images or moving images, such as a film camera and a video camera. The present invention can also be applied to a lens unit used with the camera body of these cameras.

  In the embodiment described above, the moving frame 14 is locked by the four locking arms 42 arranged at equal intervals. However, any number of locking arms of three or more may be provided. it can. Further, the intervals between the locking arms are not necessarily equal. When three locking arms are provided, they are preferably arranged around the image blur prevention lens at a central angle of about 120 °.

  Furthermore, in the above-described embodiment, the contact surface of the arm contact portion 42d and the contact surface of the locking contact portion 14b are each formed as a flat portion and are in surface contact with each other. It is also possible to form the surface in a curved surface and form the arm contact portion and the locking contact portion so that each contact surface contacts with a predetermined contact area.

  Furthermore, in the above-described embodiment, the arm contact portion and the locking contact portion are in surface contact. However, as a modification, each arm contact portion and the locking contact portion include a plurality of points. It is also possible to configure the arm contact portion and the locking contact portion so as to make point contact with each other or line contact with a plurality of linear regions. In the modification shown in FIG. 8, two abutting projections 50a are formed on the arm abutting portions of the respective locking arms 50, and when the movable portion is locked, The tip of the contact protrusion 50a simultaneously contacts the locking contact 14b of the moving frame 14. At this time, the tip of each contact protrusion 50a and the contact portion 14b for locking are in line contact with each other in a linear region extending in a direction orthogonal to the paper surface of FIG. In this way, each arm contact portion and the locking contact portion are in line contact with each other in a plurality of linear regions, so that the translation position and the rotation position of the moving frame 14 are locked at a predetermined movable portion locking position. be able to. According to this modification, the contact portions are point-contacted or surface-contacted, so that the dimensional error of the locking contact portion 14b and the arm contact portion 42d can be absorbed by elastic deformation of the contact portions. Since it can do, each contact part can be made to contact reliably.

  In the above modification, each arm contact portion and locking contact portion are in line contact in a plurality of linear regions, but each arm contact portion and locking contact portion are single. Even if they are in contact at a point or a single linear region, the rotational position of the moving frame 14 can be constrained. In the modification shown in FIG. 9, the arm contact portion 60 a of each locking arm 60 has four points P <b> 1, P <b> 2, and four points P <b> 1, P <b> 2 with respect to the surrounding wall portion 62 formed so as to surround the image blur prevention lens 16. Contact is made at P3 and P4 (linear regions extending in a direction perpendicular to the paper surface). In this modified example, the peripheral wall 62 provided in the moving frame is not cylindrical, and the radius of curvature of the outer peripheral surface is partially different.

  In this modification, the outer peripheral surface of the peripheral wall 62 has a curvature in the vicinity of the contact points P1, P2, P3, and P4 between the locking contact portions 62a and the arm contact portions 60a of the peripheral wall 62. It is constituted by an arc having a large radius. That is, the outer peripheral surface in the vicinity of the contact point P1 is formed by an arc centered at a point C1 indicated by a one-dot chain line in FIG. 9, and this arc passes through the contact points P1 to P4 about the optical axis A. The radius of curvature is larger than the radius of the circle shown by the two-dot chain line in FIG. Therefore, the distance between P1-C1 is formed longer than the distance between P1-A. In this modification, the point C1 is arranged on a straight line connecting the contact point P1 and the optical axis A. Similarly, the outer peripheral surface in the vicinity of the contact points P2, P3, and P4 is formed into a curved surface having the same curvature radius as that of the outer peripheral surface in the vicinity of the contact point P1, and the curvature radius is longer than the distance between P1 and A.

  In this modified example configured as described above, if the peripheral wall 62 is rotated around the optical axis A together with the moving frame from the state shown in FIG. 9, the outer peripheral surface near the contact point is an arc having a large curvature radius. Therefore, the distance between the contact points facing each other (the distance between the points P1 and P3 and the distance between the points P2 and P4) is increased. However, during locking, the rotation position of each locking arm 60 is fixed, and the distance between contact points facing each other does not increase. Therefore, in the state shown in FIG. 9, the rotation of the peripheral wall 62 (moving frame) around the optical axis A is prevented, and the translation position and the rotating position of the moving frame are locked.

  According to this modification, the peripheral wall 62 can be formed by a curved surface having a predetermined radius of curvature, and a part of the peripheral wall 62 can be used as the locking contact portion 62a. The contact portion 62a for use can be formed, and the contact portion 62a for locking can be easily formed.

DESCRIPTION OF SYMBOLS 1 Camera of embodiment of this invention 2 Lens unit 4 Camera main body 6 Lens barrel 8 Imaging lens 10 Anti-vibration actuator 12 Fixed plate (fixed part)
14 Moving frame (movable part)
14a Surrounding wall portion 14b Locking contact portion 16 Image blur prevention lens 18 Steel ball (movable portion supporting means)
20a First drive coil 20b Second drive coil 20c Third drive coil 22a First drive magnet 22b Second drive magnet 22c Third drive magnet 24a First magnetic sensor (first position detection element)
24b Second magnetic sensor (second position detecting element)
24c 3rd magnetic sensor (3rd position detection element)
26 Suction Yoke 30 Recess 31 Recess 34 Gyro 36 Controller (Control Unit)
40 arm support plate 40a arm bearing 42 locking arm 42a arm shaft 42b arm main body portion 42c cam follower projection 42d arm contact portion 44 arm drive plate 44a cam groove 44b tooth 46 drive motor 46a gear 48 motor support plate 50 locking arm 50a Contact projection 60 Locking arm 60a Arm contact 62 Peripheral wall 62a Locking contact

Claims (8)

An anti-vibration actuator disposed inside the lens barrel for moving the image blur prevention lens,
A fixed part;
A movable portion provided with the image blur prevention lens and having at least three locking contact portions provided around the image blur prevention lens;
Movable part support means for supporting the movable part movably with respect to the fixed part;
Driving means for applying a driving force between the fixed portion and the movable portion to drive the movable portion with respect to the fixed portion;
And at least three locking arms rotatably disposed around the image blur prevention lens so as to face each of the locking contact portions,
When these locking arms are rotated to the arm locking position, the arm contact portions of the locking arms are brought into contact with the locking contact portions, respectively. An anti-vibration actuator characterized in that the rotational position is locked at a predetermined movable part locking position.   The anti-vibration actuator according to claim 1, wherein each of the locking contact portions and each of the arm contact portions contact with a predetermined contact area when the movable portion is positioned at the movable portion locking position.   Each of the locking contact portions and each of the arm contact portions includes a flat portion, and when the movable portion is positioned at the movable portion locking position, The anti-vibration actuator according to claim 2, wherein the flat portions of the arm contact portions are in surface contact with each other.   Each of the locking contact portions and each of the arm contact portions are in point contact at a plurality of points or in line contact at a plurality of linear regions when the movable portion is positioned at the movable portion locking position. The vibration-proof actuator according to Item 1.   2. The movable portion includes a peripheral wall portion formed so as to surround the image blur prevention lens, and each of the locking contact portions is formed by cutting out the peripheral wall portion. 5. The anti-vibration actuator according to any one of items 4 to 4.   Each locking contact portion is centered on the optical axis of the image blur prevention lens, and has a curvature larger than a radius of a circle passing through each contact portion between each locking contact portion and each arm contact portion. 2. The vibration-proof actuator according to claim 1, wherein the vibration-proof actuator is configured by a curved surface having a large radius. A lens unit equipped with an anti-vibration actuator,
A lens barrel;
An imaging lens disposed inside the lens barrel;
The vibration-proof actuator according to any one of claims 1 to 6,
A lens unit comprising: A camera with an anti-vibration actuator,
The camera body,
A lens unit according to claim 7;
A camera characterized by comprising:

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