JP2007086808A - Actuator, lens unit equipped with the same, and camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator capable of stably supporting a movable part in parallel with a fixed part. <P>SOLUTION: The actuator (10) moving an image stabilizing lens includes: a fixed side member (12); a movable side member (14) to which the image stabilizing lens is attached; a movable side member supporting means (18) supporting the movable side member; at least three driving magnets (22) attached to the movable side member and arranged on the circumference of a circle centering on the optical axis of the image stabilizing lens; driving coils (20) attached to the fixed side member, to correspond to the driving magnets respectively; an attracting yoke (26) attached to the fixed side member and attracting the movable side member to the fixed side member by the magnetic force of the driving magnets; a position detecting means detecting the position of the movable side member; and a control means (36) controlling driving current flowing into each driving coil, based on the information of the detected position. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an actuator, a lens unit including the actuator, and a camera, and more particularly to an actuator for moving an image stabilizing lens, and a lens unit and a camera including the actuator.

  Japanese Patent Laid-Open No. 3-186823 (Patent Document 1) describes a vibration isolator for preventing image blurring. In this vibration isolator, the vibration of the lens barrel is detected, and the correction lens is driven in a plane parallel to the film so as not to cause image blur based on the detected vibration. The translation mechanism that translates the correction lens within a predetermined plane is, in this vibration isolator, a fixed frame that fixes the correction lens, and the fixed frame that can slide in a first direction orthogonal to the optical axis. A first holding frame to be supported, and a first holding frame that is slidably held in a second direction orthogonal to the optical axis and the first direction, and that is fixed to the lens barrel. And a frame. By combining the motions in the first and second directions perpendicular to each other, the correction lens is supported so as to be able to translate in any direction within a plane parallel to the film with respect to the lens barrel. Furthermore, this vibration isolator is provided with a dedicated linear motor for driving the correction lens in the first direction and the second direction, respectively, and by combining the drive amounts by these motors, The lens is moved in any direction.

  In any of the conventional cameras having an image blur prevention function as described above, the parallel movement mechanism that supports the correction lens so as to be movable in parallel is a member that guides the correction lens so as to be slidable in a certain direction. The correction lens is moved in an arbitrary direction by providing a combination of driving means for driving the correction lens in that direction in two orthogonal directions.

  Japanese Patent Laid-Open No. 10-319465 (Patent Document 2) describes a lens shift device. In this lens shift device, the movable member holding the lens is supported by three balls so as to be movable in parallel with respect to the fixed member. In this lens shift device, the two coil springs attract the movable member to the fixed member and prevent the movable member from rotating around the optical axis.

Japanese Patent Laid-Open No. 3-186823 JP-A-10-319465

  However, the translation device described in Japanese Patent Laid-Open No. 3-186823 described above that combines the guide means arranged in two directions orthogonal to each other and the drive means in that direction has a problem that the support mechanism becomes complicated. . In addition, when the support mechanism is complicated, the mass of the movable part of the parallel movement device increases, and thus there is a problem that high-speed parallel movement becomes difficult. Furthermore, in the conventional translation device, since sliding resistance acts between the guide means, there is a problem that the controllability when controlling the translation device is deteriorated. Also, in an actuator using guide means arranged in two orthogonal directions, the movable part can be translated in any direction within a predetermined plane, but the movable part can be rotated. There is a problem that you can not.

  On the other hand, in the lens shift device described in Japanese Patent Application Laid-Open No. 10-319465, the guide means is not used, but the movable member is attracted to the fixed member by the two coil springs and supported by contacting the three balls. . For this reason, there is a problem in that a force in the direction of shifting the movable member is generated by the coil spring, resulting in disturbance of control for shifting the lens. In addition, since the force for attracting the movable member to the fixed member by the coil spring changes depending on the position where the movable member is translated, there is a problem that it is difficult to stably support the movable member in parallel to the fixed member. .

Therefore, an object of the present invention is to provide an actuator that can respond at high speed with a simple mechanism, and a lens unit and a camera including the actuator.
Another object of the present invention is to provide an actuator capable of translating and rotating a movable part in an arbitrary direction within a predetermined plane, and a lens unit and a camera including the actuator.

  Furthermore, an object of the present invention is to provide an actuator that can stably support a movable part in parallel to a fixed part, a lens unit including the actuator, and a camera.

  In order to achieve the above object, the present invention is an actuator for moving an image stabilization lens, which is a fixed side member, a movable side member to which an image stabilization lens is attached, and the movable side member. The movable side member supporting means for supporting the movable side member on a plane parallel to the fixed side member and the fixed side member or the movable side member are attached to the optical axis of the image stabilizing lens. At least three drive magnets arranged on the center circumference, the other of the fixed side member or the movable side member, the drive coil attached to the position corresponding to each drive magnet, and the fixed For adsorbing, which is attached to a position corresponding to each driving magnet on the same side as the driving coil of the side member or the movable side member, and attracts the movable side member to the fixed side member by the magnetic force exerted by the driving magnet. Yo And a position detection means for detecting the position of the movable member, and a control means for controlling the drive current to be passed through each drive coil based on the position information detected by the position detection means. It is said.

  In the present invention configured as described above, the movable member to which the image stabilizing lens is attached is supported with respect to the fixed member by the movable member support means. The control means controls the drive current that flows through the drive coil based on the position information detected by the position detection means, and the movable member is driven and moved by the magnetic force acting between the drive coil and the drive magnet. The Further, the movable side member is attracted to the fixed side member by the magnetic force exerted on the attraction yoke by the driving magnet arranged on the circumference centering on the optical axis of the image stabilizing lens.

  According to the present invention configured as described above, the movable member is attracted to the fixed member by the magnetic force acting between the drive magnet and the attracting yoke arranged around the optical axis of the image stabilizing lens. Therefore, the movable side member can be stably supported.

In the present invention, preferably, the movable member support means is at least three spherical bodies sandwiched between the support plane portion of the fixed member and the support plane portion of the movable member.
In the present invention configured as described above, at least three spherical bodies are arranged between the fixed side member and the movable side member, and these spherical bodies are caused by the magnetic force acting between the driving magnet and the attracting yoke. And sandwiched between the respective support plane portions of the fixed side member and the movable side member.

  According to the present invention configured as described above, since the movable side member is supported by the spherical body, the sliding resistance acting on the movable side member can be reduced, and the movable side member is attracted to the fixed side member. Therefore, the spherical body can be stably supported.

In the present invention, preferably, at least three spherical bodies are arranged on a circumference centering on the optical axis of the image stabilizing lens.
According to the present invention configured as described above, since each spherical body is arranged on the circumference centering on the optical axis of the image stabilizing lens, the clamping force acting on each spherical body is sufficiently dispersed. Can be made.

In the present invention, preferably, at least three drive magnets are arranged inside the circumference on which the spherical body is arranged.
According to the present invention configured as described above, since each driving magnet is arranged inside the circumference where the spherical body is arranged, the movable member can be supported more stably.

In the present invention, preferably, at least three spherical bodies are arranged at equal intervals on the circumference.
According to the present invention configured as described above, since the spherical bodies are arranged at equal intervals on the circumference, the clamping force acting on the spherical bodies can be more uniformly dispersed.

In the present invention, preferably, the drive magnets are arranged at equal intervals on the circumference.
According to the present invention configured as described above, since the driving magnets are arranged at equal intervals on the circumference, it is possible to more uniformly disperse the attracting force that attracts the movable member to the fixed member. .

In the present invention, preferably, three driving magnets are arranged, and the optical axis of the image stabilizing lens passes through the inside of a triangle having each driving magnet as a vertex.
According to the present invention thus configured, the optical axis of the image stabilizing lens passes through the inside of the triangle with each driving magnet as the apex, and therefore, the attracting force around the optical axis can be reduced with the minimum number of driving magnets. Can be dispersed.

In the present invention, preferably, three spherical bodies are arranged at equal intervals on the circumference, and each spherical body is arranged between the drive magnets.
According to the present invention configured as described above, since the three spherical bodies are arranged at equal intervals on the circumference, the movable side member can be stably supported and each spherical body is driven by each drive. Since it is arrange | positioned between the magnets for use, it can clamp by uniform force with each spherical body.

In the present invention, preferably, the attracting force exerted by each drive magnet on each attracting yoke is the same.
According to the present invention configured as described above, a uniform attracting force can be applied to the movable member by arranging the driving magnets at equal intervals on the circumference.

The lens unit of the present invention includes a lens barrel, an imaging lens disposed in the lens, and the actuator of the present invention attached to the lens barrel.
The camera of the present invention includes the lens unit of the present invention.

According to the present invention, it is possible to provide a translation device capable of responding at high speed with a simple mechanism, and an actuator, a lens unit, and a camera including the translation device.
In addition, according to the present invention, it is possible to provide a translation device capable of translating and rotating a movable part in an arbitrary direction within a predetermined plane, and an actuator, a lens unit, and a camera including the translation device. .

  Furthermore, according to the actuator of the present invention, and the lens unit and camera including the actuator, the movable part can be stably supported in parallel to the fixed part.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.
First, a camera according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a camera according to a first embodiment of the present invention.
As shown in FIG. 1, the camera 1 according to the first 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 actuator 10 that moves the image stabilization lens 16 within a predetermined plane, and a lens barrel. 6 are gyroscopes 34a and 34b (only 34a is shown in FIG. 1). The camera 1 according to the first embodiment of the present invention detects vibrations by the gyros 34 a and 34 b, operates the actuator 10 based on the detected vibrations, and moves the image stabilization lens 16. The image focused on the film surface F is stabilized. In addition, the actuator 10 is comprised by providing a drive means in the parallel displacement apparatus 11 so that it may mention later. In the present embodiment, piezoelectric vibration gyros are used as the gyros 34a and 34b. In the present embodiment, the image stabilization 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 stabilization lens includes one lens and a lens group for stabilizing an image.

  Next, the actuator 10 will be described with reference to FIGS. 2 is a front partial sectional view of the actuator 10, FIG. 3 is a side sectional view taken along line AA of FIG. 2, and FIG. 4 is a top partial sectional view. 2 is a view of the actuator 10 as viewed from the film surface F side in FIG. 1, and is a view in which the fixing plate 12 is partially broken. Here, this is a front view for convenience. Shall be called. As shown in FIGS. 2 to 4, the actuator 10 is a fixed plate 12 which is a fixed side member fixed in the lens barrel 6, and a movable side member supported so as to be movable with respect to the fixed plate 12. The translation device 11 includes a moving frame 14 and three steel balls 18 that are spherical bodies that support the moving frame 14. Further, the parallel movement device 11 is configured so that the spherical body magnet 30 which is a spherical body adsorbing means for attracting the steel ball 18 to the moving frame 14 and the steel ball 18 smoothly roll between the fixed plate 12 and the moving frame 14. A steel ball receiver 31 attached to the fixed plate 12 and a steel ball receiver 32 attached to the moving frame 14 are provided. The three steel balls 18 constitute a movable side member support means, the steel ball receiver 31 constitutes a support plane part of the fixed side member, and the steel ball receiver 32 constitutes a support plane part of the movable side member.

  Further, the actuator 10 includes three driving coils 20a, 20b, and 20c attached to the fixed plate 12, and three driving parts attached to the moving frame 14 at positions corresponding to the driving coils 20a, 20b, and 20c, respectively. Magnets 22 and magnetic sensors 24a, 24b, 24c, which are position detecting means, arranged inside the drive coils 20a, 20b, 20c. Further, the actuator 10 uses the magnetic force of the attracting yoke 26 attached to the stationary plate 12 and the magnetic force of the driving magnet 22 to the stationary plate 12 to attract the moving frame 14 to the stationary plate 12 by the magnetic force of the driving magnet 22. And a back yoke 28 attached to the back side of the drive magnet 22 so as to be effectively directed to the direction. The drive coils 20a, 20b, 20c and the three drive magnets 22 attached to the corresponding positions can cause the moving frame 14 to translate and rotate with respect to the fixed plate 12. The drive means which can be comprised is comprised. The drive magnet 22 acts as a member magnet for attracting the moving frame 14 to the fixed plate 12, and the attracting yoke 26 acts as a magnetic body attracted by the member magnet.

Further, as shown in FIG. 1, the actuator 10 includes each drive coil 20a based on the vibration detected by the gyros 34a and 34b and the position information of the moving frame 14 detected by the magnetic sensors 24a, 24b and 24c. , 20b, 20c has a controller 36 which is a control means for controlling the current to flow.
The lens unit 2 is attached to the camera body 4 and configured to form incident light on the film surface F.
The generally cylindrical lens barrel 6 holds a plurality of imaging lenses 8 therein, and allows focus adjustment by moving some imaging lenses 8.

The actuator 10 moves the moving frame 14 in a plane parallel to the film surface F with respect to the fixed plate 12 fixed to the lens barrel 6, and thereby the image stabilization lens 16 attached to the moving frame 14. Is moved so that the image formed on the film surface F is not disturbed even if the lens barrel 6 vibrates.
The fixed plate 12 has a generally donut plate shape, and three driving coils 20a, 20b, and 20c are disposed thereon. As shown in FIG. 2, the centers of these three drive coils 20 a, 20 b, and 20 c are arranged on a circumference centered on the optical axis of the lens unit 2. In the present embodiment, the drive coil 20a is disposed vertically above the optical axis, the drive coil 20b is disposed in the horizontal direction with respect to the optical axis, and the drive coil 20c is respectively connected to the drive coils 20a and 20b. They are arranged at positions separated by a central angle of 135 °. Therefore, the driving coils 20a and 20b are separated by a central angle of 90 °, the driving coils 20b and 20c are separated by a central angle of 135 °, and the driving coils 20c and 20a are separated by a central angle of 135 °. . The driving coils 20a, 20b, and 20c are arranged such that their windings are wound in a rectangular shape with rounded corners, and the center line of the rectangle coincides with the radial direction of the circumference.

  The moving frame 14 has a generally donut plate shape, and is arranged in parallel with the fixed plate 12 so as to overlap the fixed plate 12. An image stabilizing lens 16 is attached to the central opening of the moving frame 14. Rectangular driving magnets 22 are respectively embedded in positions on the circumference of the moving frame 14 corresponding to the driving coils 20a, 20b, and 20c. In the present specification, the position corresponding to the driving coil means a position where the influence of the magnetic field formed by the driving coil is substantially reached. In addition, a rectangular back yoke 28 is provided on the back side of the driving magnet 22, that is, on the opposite side of each driving coil so that the magnetic flux of each driving magnet 22 is efficiently directed toward the fixed plate 12. Each is attached.

  In addition, rectangular suction yokes 26 are attached to the back side of each driving coil of the fixed plate 12, that is, on the opposite side of the moving frame 14. The moving frame 14 is attracted to the fixed plate 12 by the magnetic force exerted by each driving magnet 22 on the attracting yoke 26 attached thereto. In the present embodiment, the fixed plate 12 is made of a non-magnetic material so that the magnetic lines of force of the drive magnet 22 reach the attraction yoke 26 efficiently.

  FIG. 5A is a partially enlarged top view showing a positional relationship among the driving coil 20a, the driving magnet 22, the back yoke 28, and the attracting yoke 26, and FIG. 5B is a partially enlarged front view. As shown in FIGS. 2, 5A, and 5B, the driving magnet 22, the back yoke 28, and the attracting yoke 26 each having a rectangular shape are arranged so that the long sides and the short sides thereof overlap each other. Has been. Further, the drive coil 20a is arranged such that each side thereof is parallel to each long side and short side of the rectangular back yoke 28. Further, the drive magnet 22 is oriented so that its magnetic neutral axis C coincides with the radial direction of the circumference where each drive magnet 22 is disposed. As a result, the driving magnet 22 receives a driving force in the tangential direction of the circumference when a current flows through the corresponding driving coil. For the other driving coils 20b and 20c, corresponding driving magnets 22, back yokes 28, and attracting yokes 26 are arranged in the same positional relationship. In this specification, the magnetic neutral axis C is a line connecting points where the polarity changes from an intermediate S pole to an N pole when both ends of the driving magnet 22 are set to an S pole and an N pole, respectively. Shall be said. Therefore, in the present embodiment, the magnetic neutral axis C is positioned so as to pass through the midpoint of each long side of the rectangular driving magnet 22. Further, as shown in FIG. 5A, the polarity of the driving magnet 22 also changes in the thickness direction. In FIG. 5A, the lower left corner is the S pole, the lower right corner is the N pole, The upper left is the N pole and the upper right is the S pole.

  As shown in FIGS. 2 to 5, magnetic sensors 24a, 24b, and 24c are arranged inside the drive coils 20a, 20b, and 20c, respectively. Each magnetic sensor is arranged so that the sensitivity center point S is positioned on the magnetic neutral axis C of each drive magnet 22 when the moving frame 14 is in the neutral position. In the present embodiment, a Hall element is used as the magnetic sensor.

  6 and 7 are diagrams for explaining the relationship between the movement of the driving magnet 22 and the signal output from the magnetic sensor 24a. As shown in FIG. 6, when the sensitivity center point S of the magnetic sensor 24a is located on the magnetic neutral axis C of the driving magnet 22, the output signal from the magnetic sensor 24a is zero. When the driving magnet 22 moves together with the moving frame 14, and the sensitivity center point of the magnetic sensor 24a deviates from the magnetic neutral axis of the driving magnet 22, the output signal of the magnetic sensor 24a changes. As shown in FIG. 6, when the drive magnet 22 moves in a direction orthogonal to the magnetic neutral axis C, that is, in the X-axis direction, the magnetic sensor 24a generates a sinusoidal signal. Therefore, when the amount of movement is small, the magnetic sensor 24a outputs a signal that is substantially proportional to the distance of movement of the driving magnet 22. In the present embodiment, when the moving distance of the driving magnet 22 is within about 3% of the length of the long side of the driving magnet 22, the signal output from the magnetic sensor 24a is the sensitivity center of the magnetic sensor 24a. This is approximately proportional to the distance between the point S and the magnetic neutral axis C of the driving magnet 22. In the present embodiment, the actuator 10 operates within a range in which the output of each magnetic sensor is substantially proportional to the distance.

  As shown in FIGS. 7A to 7C, when the magnetic neutral axis C of the driving magnet 22 is positioned on the sensitivity center point S of the magnetic sensor 24a, the driving is performed as shown in FIG. 7B. When the working magnet 22 rotates, the output signal from the magnetic sensor 24a is 0 even when the driving magnet 22 moves in the direction of the magnetic neutral axis C as shown in FIG. As shown in FIGS. 7D to 7F, when the magnetic neutral axis C of the drive magnet 22 deviates from the sensitivity center point S of the magnetic sensor 24a, the sensitivity center point S is the center. A signal proportional to the size of the radius r of the circle in contact with the magnetic neutral axis C is output from the magnetic sensor 24a. Therefore, if the radius r of the circle in contact with the magnetic neutral axis C centered on the sensitivity center point S is the same, the driving magnet 22 is in a direction perpendicular to the magnetic neutral axis C as shown in FIG. When moved, the drive magnet 22 translates and rotates as shown in FIG. 7 (e), and when it moves in any direction as shown in FIG. Output from the magnetic sensor 24a.

  Although the magnetic sensor 24a has been described here, the other magnetic sensors 24b and 24c also output similar signals based on the positional relationship with the driving magnets 22 corresponding thereto. For this reason, based on the signals detected by the 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.

  As shown in FIG. 2, the three steel balls 18 are arranged on the outer circumferences of the circumferences where the driving coils of the fixed frame 12 are arranged. The three steel balls 18 are arranged at intervals of a central angle of 120 °, and one of the steel balls 18 is arranged between the drive coils 20a and 20b. As shown in FIG. 3, each steel ball 18 is attracted to the moving frame 14 by a spherical body magnet 30 embedded in the moving frame 14 at a position corresponding to each steel ball 18. Each steel ball 18 is attracted to the moving frame 14 by the spherical magnet 30, and the moving frame 14 is attracted to the fixed plate 12 by the driving magnet 22, so that each steel ball 18 is interposed between the fixed plate 12 and the moving frame 14. It will be pinched by. 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, thereby allowing translational movement and rotational movement of the moving frame 14 with respect to the fixed plate 12 in any direction. To do.

  In addition, annular steel ball receivers 31 and 32 are attached to the outer peripheral portions of the fixed plate 12 and the moving frame 14 so as to contact the steel balls 18, respectively. When the moving frame 14 moves while the steel balls 18 are sandwiched between the fixed plate 12 and the moving frame 14, each steel ball 18 rolls between the steel ball receivers 31 and 32. For this reason, even when the moving frame 14 moves relative to the fixed plate 12, no sliding friction occurs between them. Preferably, the surface of the steel ball receivers 31 and 32 is formed so as to reduce the rolling resistance between the steel ball 18 and the steel ball receivers 31 and 32, and the steel ball receivers 31 and 32 are made of a material having a high surface hardness. It is good to constitute.

  The steel ball receiver 32 is preferably made of a non-magnetic material so that the magnetic flux of the spherical body magnet 30 effectively reaches the steel ball 18. Preferably, the thickness of the steel ball receivers 31 and 32 is 0.2 to 0.5 mm. In this embodiment, in order to reduce the weight of the moving frame 14, the steel ball receiver 32 is configured by electroless nickel plating on 0.3 mm thick aluminum. In this embodiment, a steel sphere is used as the steel ball 18, but the steel ball 18 is not necessarily a sphere. That is, if the portion that contacts the steel ball receiver 32 during the operation of the actuator 10 has a substantially spherical shape, it can be used as the steel ball 18. In addition, in this specification, such a form is called a spherical body.

  Next, the control of the actuator 10 will be described with reference to FIG. FIG. 8 is a block diagram showing signal processing in the controller 36. As shown in FIG. 8, the vibration of the lens unit 2 is detected momentarily by the two gyros 34 a and 34 b and is input to arithmetic circuits 38 a and 38 b that are lens position command signal generation means built in the controller 36. In the present embodiment, the gyro 34a is configured and arranged to detect the angular acceleration of the yawing motion of the lens unit 2, and the gyro 34b is configured to detect the angular acceleration of the pitching motion.

  The arithmetic circuits 38a and 38b generate lens position command signals for instructing in time series the position at which the image stabilizing lens 16 should be moved based on the angular acceleration input from the gyros 34a and 34b every moment. That is, the arithmetic circuit 38a integrates the angular acceleration of the yawing motion detected by the gyro 34a with time and generates a horizontal component of the lens position command signal by adding a predetermined correction signal. The circuit 38b is configured to generate a vertical component of the lens position command signal based on the angular acceleration of the pitching motion detected by the gyro 34b. Even if the lens unit 2 vibrates during the exposure of photography by moving the image stabilizing lens 16 momentarily according to the lens position command signal thus obtained, the film surface in the camera body 4 The image focused on F is stabilized without being disturbed.

  The coil position command signal generating means built in the controller 36 is configured to generate a coil position command signal for each driving coil based on the lens position command signal generated by the arithmetic circuits 38a and 38b. The coil position command signal indicates the positional relationship between each drive coil 20a, 20b, 20c and the corresponding drive magnet 22 when the image stabilization lens 16 is moved to the position specified by the lens position command signal. It is a signal to represent. That is, when the drive magnet 22 corresponding to each drive coil moves to the position commanded by the coil position command signal for each drive coil, the image stabilization lens 16 is commanded by the lens position command signal. Move to the specified position. In the present embodiment, since the driving coil 20a is provided vertically above the optical axis, the coil position command signal for the driving coil 20a is the horizontal component of the lens position command signal output from the arithmetic circuit 38a. Will be equal. Further, since the driving coil 20b is provided in the lateral direction of the optical axis, the coil position command signal for the driving coil 20b is equal to the vertical component of the lens position command signal output from the arithmetic circuit 38b. Further, the coil position command signal for the driving coil 20c is generated by the arithmetic circuit 40 which is a coil position command signal generating means based on the horizontal direction component and the vertical direction component of the lens position command signal.

  On the other hand, the amount of movement of the driving magnet 22 relative to the driving coil 20a measured by the magnetic sensor 24a is amplified to a predetermined magnification by the magnetic sensor amplifier 42a. The differential circuit 44a generates a current proportional to the difference between the horizontal component of the coil position command signal output from the arithmetic circuit 38a and the amount of movement of the driving magnet 22 relative to the driving coil 20a output from the magnetic sensor amplifier 42a. It flows in the driving coil 20a. Therefore, when there is no difference between the coil position command signal and the output from the magnetic sensor amplifier 42a, no current flows through the driving coil 20a, and the driving force acting on the driving magnet 22 becomes zero.

  Similarly, the amount of movement of the driving magnet 22 relative to the driving coil 20b measured by the magnetic sensor 24b is amplified to a predetermined magnification by the magnetic sensor amplifier 42b. The differential circuit 44b generates a current proportional to the difference between the vertical component of the coil position command signal output from the arithmetic circuit 38b and the amount of movement of the driving magnet 22 relative to the driving coil 20b output from the magnetic sensor amplifier 42b. It flows in the driving coil 20b. Accordingly, when there is no difference between the coil position command signal and the output from the magnetic sensor amplifier 42b, no current flows through the driving coil 20b, and the driving force acting on the driving magnet 22 becomes zero.

  Further, the amount of movement of the driving magnet 22 relative to the driving coil 20c measured by the magnetic sensor 24c is amplified to a predetermined magnification by the magnetic sensor amplifier 42c. The differential circuit 44c generates a current proportional to the difference between the coil position command signal output from the arithmetic circuit 40 and the amount of movement of the driving magnet 22 relative to the driving coil 20c output from the magnetic sensor amplifier 42c. Flow to 20c. Accordingly, when there is no difference between the coil position command signal and the output from the magnetic sensor amplifier 42c, no current flows through the driving coil 20c, and the driving force acting on the driving magnet 22 becomes zero.

  Next, the relationship between the lens position command signal and the coil position command signal when the moving frame 14 is translated will be described with reference to FIG. FIG. 9 is a diagram showing the positional relationship between the driving coils 20 a, 20 b, 20 c arranged on the fixed plate 12 and the three driving magnets 22 arranged on the moving frame 14. First, the three driving coils 20a, 20b, and 20c have their center points arranged on points L, M, and N on the circumference of the radius R with the point Q as the origin. The magnetic sensors 24a, 24b, and 24c are also arranged so that the sensitivity center point S is located on the points L, M, and N, respectively. Further, when the moving frame 14 is in the neutral position, that is, when the center of the image stabilizing lens 16 is on the optical axis, the magnetic neutral axis C of each driving magnet 22 corresponding to each driving coil. Are also located on points L, M, and N, respectively. If the horizontal axis with the point Q as the origin is the X-axis, the vertical axis is the Y-axis, and the axis that forms an angle of 135 ° with respect to the X-axis and the Y-axis is the V-axis, the magnetism of each drive magnet 22 The target neutral axis C is at a position overlapping the X axis, Y axis, and V axis, respectively.

Here, when the moving frame 14 moves and the center point of the image stabilizing lens 16 moves to the point Q ₁ , and further, the moving frame 14 rotates counterclockwise by the angle θ around the point Q ₁ , each drive is performed. The midpoint of the magnetic neutral axis C of the working magnet 22 moves to points L ₁ , M ₁ and N ₁ , respectively. In order for the moving frame 14 to move to such a position, the magnitude of the coil position command signal for the driving coil 20a is set to the radius of a circle that touches the straight line Q ₁ L ₁ with the point L as the center, and the driving coil 20b. Is the radius of a circle that touches the straight line Q ₁ M ₁ around the point M, and the coil position command signal of the driving coil 20c is the radius of a circle that touches the straight line Q ₁ N ₁ around the point N It is necessary to be a value proportional to each. Let the radius of these circles be r _X , r _Y , and r _V , respectively.

Note that the symbols of the coil position command signals r _X , r _Y , r _V are determined as shown in FIG. That is, the moving coil position command signal r _X moving the point L ₁ to the first quadrant positive, the coil position command signal r _X to move to the second quadrant determined as negative, similarly, the point M ₁ to the first quadrant The coil position command signal _rY to be moved is determined to be positive, and the coil position command signal _rY to be moved to the fourth quadrant is determined to be negative. Also, define the coil position command signal r _V for moving the point N ₁ below the V-axis positive, and negative coil position command signal r _V for moving the upper side of the V axis. Furthermore, the sign of the angle is positive in the clockwise direction. Therefore, when the moving frame 14 is rotated clockwise from the neutral position, the coil position command signal r _X is positive, the coil position command signal r _Y is negative, and the coil position command signal r _V is negative.

Further, the coordinates of the point Q ₁ are (j, g), the coordinates of the point L ₁ are (i, e), the coordinates of the point N ₁ are (k, h), and the angle between the V axis and the Y axis is α. To do. Further, an auxiliary line A passing through the point M and parallel to the straight line Q ₁ L ₁ and an auxiliary line B passing through the point L and parallel to the straight line Q ₁ M ₁ are drawn, and the intersection of the auxiliary line A and the auxiliary line B is defined as a point P. To do.

となる。従って、

の関係が成り立つ。また、座標ｅ、ｇ、ｈ、ｉ、ｊ、ｋを、Ｒ、ｒ_X、ｒ_Y、ｒ_V、θ、αで表すと、幾何学的関係及び数式３より、

が得られる。さらに、座標（ｋ，ｇ）、（ｊ，ｇ）、（ｋ，ｈ）を頂点とする直角三角形について、下記の関係が成り立つ。

Here, when the sine theorem is applied to the right triangle LMP,

It becomes. Therefore,

The relationship holds. Further, when the coordinates e, g, h, i, j, k are represented by R, r _X , r _Y , r _V , θ, α, the geometric relationship and Equation 3

Is obtained. Further, the following relationship holds for a right triangle having apexes at coordinates (k, g), (j, g), and (k, h).

の関係が得られる。さらに、移動枠１４が並進運動する場合には、θ＝０であるから数式６は、

となる。また、本実施形態においては、α＝４５゜であるから、数式７の関係は、

と簡略化される。従って、本実施形態においては、レンズ位置指令信号によって画像安定化用レンズ１６の中心を座標（ｊ，ｇ）に並進運動させる場合、駆動用コイル２０ａに対しては座標ｊの大きさに比例したコイル位置指令信号ｒ_Xを与え、駆動用コイル２０ｂに対しては座標ｇの大きさに比例したコイル位置指令信号ｒ_Yを与え、駆動用コイル２０ｃに対しては数式８によってコイル位置指令信号ｒ_Vを計算して与える。 Expanding and organizing the relationship of Equation 5,

The relationship is obtained. Further, when the moving frame 14 moves in translation, θ = 0, so Equation 6 is

It becomes. In this embodiment, since α = 45 °, the relationship of Equation 7 is

And simplified. Therefore, in the present embodiment, when the center of the image stabilizing lens 16 is translated to the coordinates (j, g) by the lens position command signal, it is proportional to the size of the coordinate j with respect to the driving coil 20a. A coil position command signal r _X is given, a coil position command signal r _Y proportional to the magnitude of the coordinate g is given to the drive coil 20b, and a coil position command signal r is given to the drive coil 20c by Equation 8. Calculate and give _V.

The coil position command signal r _X is the output signal from the arithmetic operation circuit 38a in FIG. 8, the coil position command signal r _Y is identical with the output signal of the arithmetic circuit 38b. The coil position command signal r _V corresponds to the output signal of the arithmetic circuit 40 that performs a calculation equivalent to Equation 8.
Next, the relationship between the lens position command signal and the coil position command signal when the moving frame 14 is rotated will be described with reference to FIG. FIG. 10 is a diagram for explaining a coil position command signal when the moving frame 14 is translated and rotated. As shown in FIG. 10, first, when the moving frame 14 is translated, the center of the image stabilizing lens 16 attached thereto is moved from the point Q to the point Q _2. Are moved from points L, M, and N to points L ₂ , M ₂ , and N ₂ , respectively. Coil position command signals for this translational movement are r _X , r _Y , r _V. The magnitudes of these coil position command signals can be obtained by the above-described equation 8 or the like. Here, the coil position command signals r _Xη , r _Yη and r _Vη when the moving frame 14 is rotated counterclockwise by the angle η around the point Q ₂ are calculated.

の関係が得られる。 First, as in the case of FIG. 9, the coordinates of the point Q ₂ are (j, g), the coordinates of the contact point of the circle with the radius r _V centered on the straight line Q ₂ N ₂ and N are (k, h), Substituting 0 for θ in Equation 4,

The relationship is obtained.

の関係が成り立つ。 Next, when the moving frame 14 is rotated counterclockwise by the angle η around the point Q ₂ , the points L ₂ , M ₂ and N ₂ are moved to the points L ₃ , M ₃ and N ₃ , respectively. The angle formed by the line segments Q ₂ L ₂ and Q ₂ L is β, the angle formed by the line segments Q ₂ M ₂ and Q ₂ M is δ, and the angle formed by the line segments Q ₂ N ₂ and Q ₂ N is γ. To do. Further, the length of the line segment Q ₂ L is U, the length of the line segment Q ₂ M is W, and the length of the line segment Q ₂ N is V. Here, the magnitudes of the coil position command signals r _Xη , r _Yη , and r _Vη are the radii of circles that are in contact with the straight lines Q ₂ L ₃ , Q ₂ M ₃ , and Q ₂ N ₃ with the points L, M, and N as the centers. Are equal to each other,

The relationship holds.

さらに、数式１１の関係を数式１０に代入して、β、γ、δ等を消去すると、

の関係が得られる。従って、画像安定化用レンズ１６の中心を座標（ｊ，ｇ）に並進運動させ、さらに、その点を中心に反時計回りに角度η回転運動させた位置に移動枠１４を移動させるためには、まず、数式８及び９によってｒ_X、ｒ_Y、ｒ_Vを計算し、次に、その値を数式１２に代入することによってコイル位置指令信号ｒ_Xη、ｒ_Yη、ｒ_Vηを計算し、これらを各駆動用コイルに与えればよい。 Further, sin β, cos β, and the like can be expressed as follows from the geometric relationship.

Further, by substituting the relationship of Equation 11 into Equation 10 to eliminate β, γ, δ, etc.,

The relationship is obtained. Therefore, in order to translate the center of the image stabilizing lens 16 to the coordinates (j, g) and further move the moving frame 14 to a position where the angle η is rotated counterclockwise around that point. First, r _X , r _Y , r _V are calculated according to equations 8 and 9, and then the coil position command signals r _Xη , r _Yη , r _Vη are calculated by substituting the values into equation 12, Is given to each driving coil.

によってコイル位置指令信号ｒ_Xη、ｒ_Yη、ｒ_Vηを計算すればよい。 In addition, when the moving frame 14 is rotated counterclockwise by an angle η around the point Q without translational movement, 0 is substituted into r _X , r _Y , and r _V in Expression 12.

The coil position command signals r _Xη , r _Yη , and r _Vη may be calculated by

Next, an example of a specific circuit of the controller 36 will be described with reference to FIG. FIG. 11 shows an example of a circuit for controlling the current flowing through the driving coil 20a. In the circuit of FIG. 11, ancillary circuits such as a power supply line for operating each operational amplifier are omitted. First, as shown in FIG. 11, electrical resistances R7 and R8 are connected in series between the power supply voltage + Vcc and the ground potential GND. Further, the positive input terminal of the operational amplifier OP4 is connected between the electric resistances R7 and R8. The negative input terminal of the operational amplifier OP4 is connected to the output terminal of the operational amplifier OP4. Thus, the voltage at the output terminal of the operational amplifier OP4 is set and maintained at the reference voltage V _REF between the power supply voltage + Vcc and the ground potential GND by the electric resistors R7 and R8.

On the other hand, a power supply voltage + Vcc is applied between the first terminal and the second terminal of the magnetic sensor 24a. The third terminal of the magnetic sensor 24a is connected to the reference voltage _VREF . As a result, when the magnetism acting on the magnetic sensor 24a changes, the voltage at the fourth terminal of the magnetic sensor 24a changes between + Vcc and GND.
The fourth terminal of the magnetic sensor 24a is connected to the negative input terminal of the operational amplifier OP1 through the variable resistor VR2, and the gain of the output of the magnetic sensor 24a is adjusted by adjusting the variable resistor VR2. Further, both fixed terminals of the variable resistor VR1 are connected to + Vcc and GND, respectively. The movable terminal of the variable resistor VR1 is connected to the negative input terminal of the operational amplifier OP1 through the electric resistor R1. By adjusting the variable resistor VR1, the offset voltage of the output of the operational amplifier OP1 is adjusted. The plus input terminal of the operational amplifier OP1 is connected to the reference voltage V _REF . The output terminal of the operational amplifier OP1 is connected to the negative input terminal of the operational amplifier OP1 through the electric resistance R2.

  An arithmetic circuit 38a that outputs a coil position command signal for the driving coil 20a is connected to the plus input terminal of the operational amplifier OP3. The output terminal of the operational amplifier OP3 is connected to the negative input terminal of the operational amplifier OP3. Therefore, the operational amplifier OP3 acts as a buffer amplifier for the coil position command signal.

The output terminal of the operational amplifier OP1 is connected to the negative input terminal of the operational amplifier OP2 through the electric resistance R3. The output terminal of the operational amplifier OP3 is connected to the positive input terminal of the operational amplifier OP2 via the electric resistor R4. For this reason, the difference between the output of the magnetic sensor 24a and the coil position command signal is output from the output terminal of the operational amplifier OP2. The positive input terminal of the operational amplifier OP2 is connected to the reference voltage V _REF through the electric resistor R5, and the output terminal of the operational amplifier OP2 is connected to the negative input terminal of the operational amplifier OP2 through the electric resistor R6. These electric resistances R5 and R6 set the negative and positive gains.

The output terminal of the operational amplifier OP2 is connected to one end of the drive coil 20a, and the other end of the drive coil 20a is connected to the reference voltage _VREF . Accordingly, a current corresponding to the potential difference between the output of the operational amplifier OP2 and the reference voltage _VREF flows through the driving coil 20a. When a current flows through the driving coil 20a, a magnetic field is generated, and a magnetic force is applied to the driving magnet 22 to move the driving magnet 22. This magnetic force acts in a direction in which the driving magnet 22 approaches the position commanded by the coil position command signal. When the driving magnet 22 is moved, the voltage output from the fourth terminal of the magnetic sensor 24a changes. When the driving magnet 22 moves to the position commanded by the coil position command signal, the voltages input to the positive input terminal and the negative input terminal of the operational amplifier OP2 become equal, and no current flows through the driving coil 20a.

The above-described operational amplifier OP1 in FIG. 11 corresponds to the magnetic sensor amplifier 42a in FIG. 8, and the operational amplifier OP2 corresponds to the differential circuit 44a. Further, although the circuit for controlling the current flowing through the driving coil 20a has been described with reference to FIG. 11, the current flowing through the driving coil 20b can also be controlled by the same circuit. The current flowing through the driving coil 20c can be controlled by a similar circuit. In this case, the output of the arithmetic circuit 40 is connected to the plus input terminal of the operational amplifier OP3. The arithmetic circuit 40 can be configured by a differential circuit similar to the operational amplifier OP2 and an electric resistor that divides the output into (1/2) ^1/2 .

  Next, the operation of the camera 1 according to the first embodiment of the present invention will be described with reference to FIGS. First, by turning on a start switch (not shown) of the camera shake prevention function of the camera 1, the actuator 10 provided in the lens unit 2 is operated. The gyros 34a and 34b attached to the lens unit 2 detect vibrations in a predetermined frequency band every moment and output them to the arithmetic circuits 38a and 38b built in the controller 36. The gyro 34a outputs an angular acceleration signal in the yawing direction of the lens unit 2 to the arithmetic circuit 38a, and the gyro 34b outputs an angular acceleration signal in the pitching direction to the arithmetic circuit 38b. The arithmetic circuit 38a integrates the input angular acceleration signal twice in time to calculate the yawing angle, and adds a predetermined correction signal thereto to generate a horizontal lens position command signal. Similarly, the arithmetic circuit 38b integrates the input angular acceleration signal twice in time to calculate a pitching angle, and adds a predetermined correction signal to this to generate a lens position command signal in the vertical direction. An image focused on the film surface F of the camera body 4 by moving the image stabilization lens 16 momentarily to the position commanded by the lens position command signal output in time series by the arithmetic circuits 38a and 38b. Is stabilized.

Horizontal direction of the lens position command signal outputted by the arithmetic circuit 38a is input as a coil position command signal r _X to the actuation circuit 44a for driving coil 20a. Similarly, the vertical lens position command signal output by the arithmetic circuit 38b is input to the operation circuit 44b as a coil position command signal _rY for the drive coil 20b. The arithmetic circuit 38a, the output of 38b is input to the arithmetic circuit 40, the operation expressed by Equation 8, the coil position command signal r _V for the actuating coil 20c is produced.

  On the other hand, the magnetic sensor 24a disposed inside the driving coil 20a is the magnetic sensor amplifier 42a, the magnetic sensor 24b inside the driving coil 20b is the magnetic sensor amplifier 42b, and the magnetic sensor 24c inside the driving coil 20c is the magnetic sensor 24c. A detection signal is output to the magnetic sensor amplifier 42c. The detection signals of the magnetic sensors amplified by the magnetic sensor amplifiers 42a, 42b, and 42c are input to the operation circuits 44a, 44b, and 44c, respectively.

The operation circuits 44a, 44b, 44c generate voltages corresponding to the differences between the input detection signals of the magnetic sensors and the coil position command signals r _X , r _Y , r _V , respectively, and generate currents proportional to these voltages. The current flows through the driving coils 20a, 20b, and 20c. When a current flows through each driving coil, a magnetic field proportional to the current is generated. Due to this magnetic field, each driving magnet 22 arranged corresponding to each driving coil receives a driving force in a direction approaching the position specified by the coil position command signals r _X , r _Y , r _V. When each driving magnet 22 receives a driving force, the steel ball 18 held between the moving frame 14 and the fixed plate 12 rolls, and the moving frame 14 to which the driving magnet 22 is attached moves within the same plane. Move it smoothly. At this time, since the steel ball 18 rolls on the steel ball receivers 31 and 32, the resistance to movement of the moving frame 14 is only rolling resistance, and sliding resistance does not act. Therefore, the moving frame 14 has a small driving force. Is moved smoothly. Further, since the steel ball 18 and the steel ball receivers 31 and 32 are made of a material having a high surface hardness, the rolling resistance between the steel ball 18 and the steel ball receivers 31 and 32 is particularly small.
When the driving magnet 22 reaches the position specified by the coil position command signal by this driving force, the coil position command signal and the detection signal of the magnetic sensor coincide with each other, so the output of the operating circuit becomes 0 and the driving force also becomes 0. . Further, when each driving magnet 22 deviates from the position specified by the coil position command signal due to a disturbance, a change in the coil position command signal, or the like, a current is again supplied to each driving coil, and each driving magnet 22 is driven. Is returned to the position specified by the coil position command signal.

  By repeating the above operation every moment, the image stabilization lens 16 attached to the moving frame 14 having the respective drive magnets 22 is moved so as to follow the lens position command signal. Thereby, the image focused on the film surface F of the camera body 4 is stabilized.

  In the camera according to the first embodiment of the present invention, the moving frame of the actuator for image stabilization can be moved in an arbitrary direction without using two orthogonal directions of guides. Can be configured. In the camera according to the first embodiment of the present invention, the moving frame of the image stabilization actuator can be translated and rotated in an arbitrary direction within a predetermined plane.

Further, in the camera according to the first embodiment of the present invention, since the moving frame of the translation device provided in the actuator is supported by the steel ball, the sliding resistance substantially acts on the movement of the moving frame. Therefore, the moving frame can be smoothly moved with a small driving force. Furthermore, by simplifying the mechanism, the moving frame of the translation device can be reduced in weight, and the moving frame can be moved with a small driving force, so that an actuator capable of high-speed response can be configured. it can.
In the camera according to the first embodiment of the present invention, since the moving magnet attracts the moving frame by the magnetic force exerted on the attracting yoke by the driving magnet, the moving frame is stably supported in parallel to the fixed plate. Can do.

  As mentioned above, although 1st Embodiment of this invention was described, a various change can be added to embodiment mentioned above. In particular, in the first embodiment described above, the present invention is applied to a film camera. However, the present invention can be applied to any camera for capturing still images or moving images, such as a digital camera or a video camera. The present invention can also be applied to a lens unit used with the camera body of these cameras. Furthermore, the present invention can be applied to any parallel movement mechanism such as an XY stage in addition to driving a lens for stabilizing an image of a camera.

In the first embodiment described above, the steel ball is attracted to the moving frame by the spherical body magnet attached to the moving frame, but the spherical body magnet is attached to the fixed plate, and the steel ball is fixed to the fixed plate. It can also be configured to be adsorbed on the surface.
Furthermore, in the first embodiment described above, the spherical steel ball is attracted to the moving frame by magnetic force, but the spherical body is attracted to the moving frame or fixed plate by other forces such as electrostatic force. It can also be configured.
In the first embodiment described above, the moving frame is supported by the steel balls that are three spherical bodies with respect to the fixed plate. However, the moving frame may be supported by four or more spherical bodies. .

  In the first embodiment described above, the driving coil is attached to the stationary member and the driving magnet is attached to the movable member. However, the driving magnet is driven to the stationary member and the movable member is driven. Coils can also be attached. Furthermore, in the first embodiment described above, three sets of driving coils and driving magnets are used, but four or more sets of driving coils and driving magnets may be used. In the first embodiment described above, a permanent magnet is used as the drive magnet, but an electromagnet can also be used as the drive magnet.

  Furthermore, in the first embodiment described above, a magnetic sensor that detects the magnetism of the driving magnet and measures its position is used as the position detection means, but the position of each driving magnet with respect to each driving coil is used. Any position detecting sensor other than the magnetic sensor for detecting the position can be used as the position detecting means.

  Furthermore, in the first embodiment described above, driving is performed such that the central angle between the driving coils 24a and 24b is 90 degrees, and the central angle between the driving coil 24c and the driving coils 24a and 24b is 135 degrees. The driving coil 24c may be arranged so that the central angle between the driving coils 24b and 24c is (90 + α) degrees and 0 ≦ α ≦ 90. In this case, the coil position command signal for the drive coil 24c can be calculated by Equation 7. Alternatively, the central angle between the driving coils 24a and 24b may not be 90 degrees, and the central angle between the three driving coils may be set to 120 °, for example. The angle can be any angle between 90 degrees and 180 degrees.

  In the first embodiment described above, the magnetic neutral axes of the drive magnets are all directed in the radial direction. However, the magnetic neutral axes of the drive magnets can be directed in any direction. . Preferably, the magnetic neutral axis of the at least one drive magnet is arranged substantially radially.

FIG. 12 is a diagram showing a driving magnet in which the magnetic neutral axis of the driving magnet 22 corresponding to the driving coils 24a and 24b is directed in the tangential direction of a circle centered on the point Q in the first embodiment of the present invention described above. A modification is shown in which the magnetic neutral axis of the drive magnet 22 corresponding to the coil 24c is directed in the radial direction. Although not shown, the driving coil 24a is arranged at the point L, the driving coil 24b is arranged at the point M, and the driving coil 24c is arranged at the point N, respectively. In this example, the coil position command signal r _X for the drive coil 24 a disposed at the point L, the coil position command signal r _y for the drive coil 24 b disposed at the point M, and the drive coil 24 c disposed at the point N. the coil position command signal r _V is given for. This command signal, in the neutral position of the moving frame 14, the point L, M, midpoints of the magnetic neutral axes of the actuating magnets 22 which are located on the N is the point L _4, M _4, N ₄ The center point of the image stabilizing lens 16 is moved from the point Q to the point Q ₃ .

In this modification, the coil position command signal r _X corresponding to the horizontal component of the lens position command signal is given to the driving coil 24b which are arranged point M, the coil position corresponding to the vertical component command signal r _Y is given to the drive coil 24a arranged at the point L. In the example of FIG. 12, when the coil position command signals r _X and r _Y are substituted into Equation 8 and the obtained coil position command signal r _V is given to the driving coil 24c, the point Q is − in the X-axis direction. r _X, is r _Y translation in the Y axis direction.

Next, with reference to FIG. 13, the further modification of 1st Embodiment of this invention is demonstrated. The actuator 45 of this modification is different from the first embodiment described above in that it has a locking mechanism for locking the moving frame 14 to the fixed plate 12 when the moving frame 14 is not controlled. .
As shown in FIG. 13, in the actuator 45 of this modification, three engagement protrusions 14 a are formed on the outer periphery of the moving frame 14. Further, an annular member 46 disposed so as to surround the moving frame 14 is attached to the fixed plate 12, and formed on the inner peripheral portion of the annular member 46 so as to engage with the engaging protrusions 14 a, respectively. Three engaged portions 46a are provided. Further, three movable side holding magnets 48 are attached to the outer periphery of the moving frame 14. In addition, at the positions corresponding to the movable side holding magnets 48 on the inner periphery of the annular member 46, there are three fixed side holding magnets 50 positioned so as to exert a magnetic force with the movable side holding magnet 48, respectively. It is attached. Further, the manual locking member 52 is provided so as to be movable in the circumferential direction of the annular member 46 so as to extend radially inward from the outside of the annular member 46. A U-shaped recess 52 a is formed at the tip of the manual locking member 52. An engaging pin 54 is attached to the outer periphery of the moving frame 14 so as to be received in the U-shaped recess 52 a and to engage with the manual locking member 52.

  Next, the operation of the actuator 45 will be described. First, by rotating the moving frame 14 of the actuator 45 counterclockwise in FIG. 13, the engaging protrusions 14 a on the outer periphery of the moving frame 14 are engaged with the engaging portions 46 a of the annular member 46, respectively. Is locked to the fixed plate 12. Further, the movable side holding magnet 48 provided on the moving frame 14 and the fixed side holding magnet 50 of the annular member 46 hardly exert a magnetic force in the state shown in FIG. When the moving frame 14 is driven to rotate counterclockwise and the movable side holding magnet 48 approaches the fixed side holding magnet 50, the fixed side holding magnet 50 generates a magnetic force in a direction that rotates the moving frame 14 clockwise. , It affects the moving frame 14. When the moving frame 14 is further rotated counterclockwise against this magnetic force, and the movable side holding magnet 48 passes the fixed side holding magnet 50, the fixed side holding magnet 50 counteracts the moving frame 14. A magnetic force in the direction of clockwise rotation is exerted on the moving frame 14. Due to this magnetic force, the engagement protrusion 14a is pressed against the engagement portion 46a, and the engagement state between the engagement protrusion 14a and the engagement portion 46a is maintained. Thereby, even when the power of the actuator 45 is turned off, the engagement state of the engagement protrusion 14 a and the engagement portion 46 a is maintained, and the moving frame 14 is locked to the fixed plate 12.

Further, when the manual locking member 52 is manually rotated counterclockwise in FIG. 13, the engaging pin 54 of the moving frame 14 is engaged with the U-shaped recess 52a, and the moving frame 14 is also anti-clockwise. It is rotated clockwise. Thereby, the engagement protrusion 14a and the engagement part 46a are manually engaged. Conversely, when the manual locking member 52 is manually rotated clockwise in FIG. 13, the moving frame 14 is rotated clockwise, and the engagement state of the engagement protrusion 14a and the engagement portion 46a is released. Is done.
Since the actuator of the present embodiment can also rotate the moving frame, it is possible to easily realize the locking mechanism as in this modification.

Next, a translation device according to a second embodiment of the present invention will be described with reference to FIGS. The translation device according to the second embodiment of the present invention generally corresponds to a device excluding the actuator driving means used in the camera of the first embodiment. Accordingly, here, only the parts different from the first embodiment of the second embodiment of the present invention will be described, and the same parts will be denoted by the same reference numerals and the description thereof will be omitted.
14 is a partial front sectional view of the translation device 100, FIG. 15 is a side sectional view, and FIG. 16 is a rear view. FIG. 14 is a view of the parallel movement device 100 as seen from the side of the fixed plate 112, and is a view showing the fixed plate 112 partially cut away. Here, for convenience, this is a front view. Shall be called.

  As shown in FIGS. 14 to 16, the parallel movement device 100 includes a fixed plate 112 that is a fixed member, a moving frame 114 that is a movable member supported to be movable with respect to the fixed plate 112, And three steel balls 18 that are spherical bodies that support the moving frame 114. An image stabilizing lens 16 is attached to the center of the moving frame 114. Further, the parallel movement device 100 includes a spherical magnet 30 that attracts the steel balls 18, a steel ball receiver 31 attached to the fixed plate 112, and a steel ball receiver 32 attached to the moving frame 114. The parallel movement device 100 includes three member magnets 122 attached to the moving frame 114, three suction yokes 126 attached to the fixed plate 112 at positions corresponding to the member magnets 122, and members. In order to direct the magnetic flux of the working magnet 122 to the attracting yoke 126, three back yokes 128 attached to the back surface of the member magnet 122 are provided. The member magnet 122, the attracting yoke 126, and the back yoke 128 constitute a movable member attracting means.

  The member magnet 122, the attracting yoke 126, and the back yoke 128 are disposed on the first circumference on the fixed plate 112 and the moving frame 114, respectively, at intervals of a central angle of 120 °. The member magnet 122, the attracting yoke 126, and the back yoke 128 are rectangular plates having substantially the same size and shape, and are positioned so that their long sides are parallel to the tangent to the first circumference. Has been. As shown in FIG. 15, the member magnets 122, the suction yoke 126, and the back yoke 128 are arranged so as to overlap each other, so that the magnetic flux of the member magnet 122 corresponds to the suction magnet by the back yoke 128. The moving frame 114 is directed to the yoke 126 and is attracted to the fixed plate 112.

  The three spherical magnets 30 are respectively arranged on the moving frame 114 at intervals of a central angle of 120 ° on the second circumference outside the first circumference. Further, as shown in FIG. 16, the three spherical magnets 30 are located between the member magnets 122 and the like arranged at equal intervals, that is, at a position with a central angle of 60 ° from the member magnets 122 and the like. Each is arranged. The three steel balls 18 are attracted to each spherical body magnet 30 and positioned at the same position as each spherical body magnet 30. Each steel ball 18 is attracted to the moving frame 114 by each spherical body magnet 30, and the moving frame 114 is attracted to the fixed plate 112 by the magnetic flux of the member magnet 122. It is sandwiched between the fixed plates 112.

  When using the translation device according to the second embodiment of the present invention, a driving force is applied to the moving frame 114 by any driving means, and the moving frame 114 is moved in a plane parallel to the fixed plate 112. . At this time, the moving frame 114 is moved with respect to the fixed plate 112 when the steel ball 18 rolls on the steel ball receivers 31 and 32. Since the moving frame 114 is supported by the three steel balls 18, only a slight rolling resistance of the steel balls 18 acts on the moving frame 114, and sliding resistance hardly acts.

  According to the translation device according to the second embodiment of the present invention, since the sliding resistance against the movement of the moving frame does not act, the moving frame can be moved with a small driving force.

  Next, an actuator according to a third embodiment of the present invention will be described with reference to FIGS. The translation device according to the third embodiment of the present invention generally corresponds to the actuator used in the camera of the first embodiment, and the first feature is that the moving frame is adsorbed to the fixed plate by the elasticity of the elastic member. Different from one embodiment. Accordingly, here, only the parts different from the first embodiment of the third embodiment of the present invention will be described, and the same parts will be denoted by the same reference numerals and description thereof will be omitted.

  17 is a partial front sectional view of the actuator 200, FIG. 18 is a side sectional view, and FIG. 19 is a rear view. FIG. 17 is a view of the actuator 200 as viewed from the side of the fixed plate 212, and is a view in which the fixed plate 212 is partially cut away. Here, for convenience, this is referred to as a front view. Shall.

  As shown in FIGS. 17 to 19, the actuator 200 includes a fixed plate 212 that is a fixed side member, a moving frame 214 that is a movable side member to which the image stabilizing lens 16 is attached, and three spherical bodies. Steel balls 18. Further, the actuator 200 has a spherical body magnet 30 which is a spherical body attracting means, a steel ball receiver 31 attached to the fixed plate 12, and a steel ball receiver 32 attached to the moving frame 214. The three steel balls 18 constitute a movable side member support means, the steel ball receiver 31 constitutes a support plane part of the fixed side member, and the steel ball receiver 32 constitutes a support plane part of the movable side member.

  Furthermore, the actuator 200 is attached to the three driving coils 220a, 220b, 220c (220c not shown) attached to the fixed plate 212, and the moving frame 214 at positions corresponding to the respective driving coils. It has three driving magnets 222 (only two are shown) and magnetic sensors 224a, 224b, and 224c (224c are not shown) as position detecting means arranged inside each driving coil. In addition, the actuator 200 includes back yokes 228 attached to the back side of the driving magnet 222 so as to effectively direct the magnetic force of each driving magnet 222 toward the fixed plate 212. Each drive coil and each drive magnet constitute a drive unit that can translate and rotate the moving frame 214 relative to the fixed plate 212.

  As shown in FIG. 17, the three steel balls 18 are arranged on the outer circumferences of the circumferences where the driving coils of the fixed frame 212 are arranged. The three steel balls 18 are arranged at intervals of a central angle of 120 °, and the steel balls 18 are arranged so as to be positioned between the drive coils. As shown in FIG. 18, each steel ball 18 is attracted to the moving frame 214 by the spherical body magnet 30 embedded in the moving frame 214 at a position corresponding to each steel ball 18. Each steel ball 18 is sandwiched between the fixed plate 212 and the moving frame 214. As a result, the moving frame 214 is supported on a plane parallel to the fixed plate 212, and each steel ball 18 is rolled while being sandwiched to allow translational movement and rotational movement of the moving frame 214 with respect to the fixed plate 212 in any direction. To do.

  Further, annular steel ball receivers 31 and 32 are attached to the outer peripheral portions of the fixed plate 212 and the moving frame 214 so as to contact the steel balls 18, respectively. When the moving frame 214 moves while the steel balls 18 are sandwiched between the fixed plate 212 and the moving frame 14, each steel ball 18 rolls between the steel ball receivers 31 and 32. For this reason, even when the moving frame 214 moves relative to the fixed plate 212, sliding friction does not occur between them.

  The fixed plate 212 has a generally donut-shaped disk shape, and a generally donut-shaped fixed plate-side substrate 230 is attached on a concentric circle. Similarly, the moving frame 214 is also generally donut-shaped disk-shaped, and a generally donut-shaped moving frame-side substrate 234 is attached on a concentric circle. As shown in FIG. 18, on the first circumference of the fixed plate 212 and the moving frame 214, three through holes 212a and 214a are provided at intervals of a central angle of 120 °, respectively. The positions of 214a are aligned. A spring 232 that is an elastic body is disposed in each of the through holes 212a and 214a.

  One end of each spring 232 extends linearly in the axial direction of the spring, and a hook is formed at the other end. The linear end of each spring 232 is passed through a small hole formed at a position corresponding to each through hole 212 a of the fixed plate side substrate 230 and soldered to the fixed plate side substrate 230. On the other hand, the end portion of each spring 232 on which the hook is formed is hooked by a claw portion 234a formed at a position corresponding to each through hole 214a of the moving frame side substrate 234 and soldered to the moving frame side substrate 234. . Since the hook of each spring 232 is hooked on the claw portion 234a in the stretched state, the moving frame 214 is pulled toward the fixed plate 212 by the elastic force of each spring 232 and is adsorbed. As a result, each steel ball 18 is sandwiched between the fixed plate 212 and the moving frame 214. Further, the through holes 212a and 214a are sufficiently large so that the spring 232 does not come into contact with the inner walls of the through holes 212a and 214a when the moving frame 214 is moved in parallel with the fixed plate 212 within the range of actual use. It is formed in size. Further, since the moving frame side substrate 234 attached to the moving frame 214 and the fixed plate side substrate 230 attached to the fixed plate 212 are connected by the spring 232, the spring 232 is moved with the fixed plate side substrate 230. It can also be used as a conductor for conducting an electrical signal between the frame side substrates 234.

  The action of the actuator 200 of the third embodiment of the present invention is the same as that of the actuator 10 used in the first embodiment of the present invention except that the moving frame 214 is attracted to the fixed plate 212 by the spring 232. Therefore, explanation is omitted.

  According to the actuator according to the third embodiment of the present invention, since the sliding resistance against the movement of the moving frame does not act, the moving frame can be moved with a small driving force.

It is sectional drawing of the camera by 1st Embodiment of this invention. It is the front fragmentary sectional view which fractured | ruptured and showed a part of actuator used for the camera by 1st Embodiment of this invention. FIG. 3 is a side cross-sectional view of the actuator used in the camera according to the first embodiment of the present invention, taken along line AA in FIG. 2. FIG. 3 is a partial top sectional view of an actuator used in the camera according to the first embodiment of the present invention. (A) The partial enlarged top view which shows the positional relationship of a drive coil, a drive magnet, a back yoke, and the attraction | suction yoke, (b) A partial enlarged front view. It is a figure which shows the relationship between the movement of a drive magnet, and the signal output from a magnetic sensor. It is a figure which shows the relationship between the movement of a drive magnet, and the signal output from a magnetic sensor. It is a block diagram which shows the signal processing in a controller. It is a figure which shows the positional relationship of the drive coil arrange | positioned on a stationary plate, and the three drive magnets arrange | positioned on a moving frame. It is a figure explaining a coil position command signal when a movement frame carries out translation movement and rotation movement. It is a circuit diagram which shows an example of the circuit which controls the electric current sent through a drive coil. It is a figure which shows the modification of the actuator in 1st Embodiment of this invention. It is a figure which shows the further modification of the actuator in 1st Embodiment of this invention. It is the front fragmentary sectional view which fractured | ruptured and showed a part of translation apparatus by 2nd Embodiment of this invention. It is side surface sectional drawing of the parallel displacement apparatus by 2nd Embodiment of this invention. It is a rear view of the parallel displacement apparatus by 2nd Embodiment of this invention. It is the front fragmentary sectional view which fractured | ruptured and showed a part of actuator by 3rd Embodiment of this invention. It is side surface sectional drawing of the actuator by 3rd Embodiment of this invention. It is a rear view of the actuator by 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera 2 Lens unit 4 Camera main body 6 Lens barrel 8 Imaging lens 10 Actuator 11 Parallel displacement device 12 Fixed plate 14 Moving frame 16 Image stabilization lens 18 Steel ball 20a Driving coil 20b Driving coil 20c Driving coil 22 Driving magnet 24a Magnetic sensor 24b Magnetic sensor 24c Magnetic sensor 26 Suction yoke 28 Back yoke 30 Spherical magnet 31 Steel ball receiver 32 Steel ball receiver 34a Gyro 34b Gyro 36 Controller 38a arithmetic circuit 38b arithmetic circuit 40 arithmetic circuit 42a magnetic sensor Amplifier 42b Magnetic sensor amplifier 42c Magnetic sensor amplifier 44a Differential circuit 44b Differential circuit 44c Differential circuit 45 Actuator 46 of the modification of the first embodiment of the present invention 46 Annular member 6a Engaging portion 48 Movable holding magnet 50 Fixed holding magnet 52 Manual locking member 52a U-shaped recess 54 Engaging pin 100 Parallel moving device 112 Fixed plate 114 Moving frame 122 Member magnet 126 Adsorption yoke 128 Back yoke 200 Actuator 212 Fixed plate 214 Moving frame 220a Driving coil 220b Driving coil 220c Driving coil 222 Driving magnet 224a Magnetic sensor 224b Magnetic sensor 224c Magnetic sensor 228 Back yoke 230 Fixed plate side substrate 232 Spring 234 Moving frame side substrate

Claims (11)

An actuator for moving an image stabilization lens,
A fixed side member;
A movable member to which the image stabilizing lens is attached;
Movable side member supporting means for movably supporting the movable side member on a plane parallel to the fixed side member;
At least three driving magnets mounted on either one of the fixed side member or the movable side member and disposed on a circumference centered on the optical axis of the image stabilizing lens;
A driving coil attached to a position corresponding to each of the driving magnets on the other of the fixed side member or the movable side member;
The movable side member is attached to the same side of the fixed side member or the movable side member as the drive coil at a position corresponding to each of the drive magnets, and the movable side member is moved by the magnetic force exerted by the drive magnet. A suction yoke to be attracted to the stationary member;
Position detecting means for detecting the position of the movable member;
Control means for controlling the drive current flowing through each of the drive coils based on the position information detected by the position detection means;
An actuator comprising:   2. The actuator according to claim 1, wherein the movable side member support means is at least three spherical bodies sandwiched between a support plane portion of the fixed side member and a support plane portion of the movable side member.   The actuator according to claim 2, wherein the at least three spherical bodies are arranged on a circumference centering on an optical axis of the image stabilizing lens.   The actuator according to claim 3, wherein the at least three driving magnets are arranged inside a circumference on which the spherical body is arranged.   The actuator according to claim 3 or 4, wherein the at least three spherical bodies are arranged at equal intervals on a circumference centered on the optical axis of the image stabilizing lens.   The actuator according to any one of claims 1 to 5, wherein the driving magnets are arranged at equal intervals on a circumference centered on the optical axis of the image stabilizing lens.   7. The drive magnet according to claim 1, wherein three drive magnets are arranged, and an optical axis of the image stabilization lens passes through an inner side of a triangle having the respective drive magnets as apexes. Actuator.   Three spherical bodies are arranged at equal intervals on a circumference centered on the optical axis of the image stabilizing lens, and the spherical bodies are arranged between the driving magnets. Item 8. The actuator according to Item 7.   The actuator according to any one of claims 1 to 8, wherein the attraction force exerted on each attraction yoke by each of the driving magnets is the same. A lens barrel;
An imaging lens arranged in the lens barrel;
The actuator according to any one of claims 1 to 9, which is attached to the lens barrel;
A lens unit comprising:   A camera comprising the lens unit according to claim 10.

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