JP2008304850A - Actuator, and lens unit equipped therewith and camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator capable of restraining the rotational movement of a movable part while allowing the translational movement of the movable part by rolling of a rolling member. <P>SOLUTION: The actuator (10) for preventing image blur by moving an imaging lens (16) on a plane orthogonal to the optical axis thereof is equipped with: a fixed part (12); an intermediate support part (13); a first rolling member (18) held between the fixed part and the intermediate support part, and supporting the intermediate support part relative to the fixed part so that the intermediate support part may move in a first direction on the plane orthogonal to the optical axis; the movable part (14) to which the imaging lens is attached; a second rolling member (19) held between the intermediate support part and the movable part, and supporting the movable part relative to the intermediate support part so that the movable part may move in a second direction different from the first direction on the plane orthogonal to the optical axis; and drive means (20 and 22) driving the movable part relative to the fixed part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an actuator, a lens unit including the same, and a camera, and more particularly, an actuator for moving an imaging lens in a plane perpendicular to the optical axis thereof to prevent image blur, and a lens including the actuator. It relates to units and cameras.

  Japanese Patent Laid-Open No. 2002-196382 (Patent Document 1) describes a shake correction apparatus. In this shake correction device, the shift member to which the lens for shake correction is attached is supported by three balls with respect to the fixed portion, whereby the lens for shake correction in the plane orthogonal to the optical axis. Allow movement. As described above, when the movable portion (shift member) is supported by the rolling member (ball), the movable member is allowed to move due to the rolling member rolling, so that the sliding resistance when moving the movable portion is reduced. There is an advantage that it can be suppressed.

JP 2002-196382 A JP-A-8-152659

  However, in the shake correction apparatus described in Japanese Patent Laid-Open No. 2002-196382, the rotational movement of the movable part is not restricted. For this reason, when the driving force in the X direction and the Y direction is applied to the movable part by the two linear motors, an unnecessary rotational movement is generated in the movable part in addition to the translational movement. There is a problem that the accuracy of shake correction control deteriorates.

  Japanese Patent Laid-Open No. 8-152659 discloses a vibration isolator in which a movable part is supported by a sphere. In this vibration isolator, an L-shaped support shaft is used to prevent rotation of the movable portion, and the support shaft is configured to slide relative to the movable portion. For this reason, a large sliding resistance acts when the movable part is moved.

  On the other hand, in the shake correction apparatus described in Japanese Patent Application Laid-Open No. 2002-196382, the ball is rolled on a flat receiving surface. For this reason, when the clamping force which clamps a rolling member (ball) is large, the surface pressure which acts on a receiving surface becomes very large, and the problem that a receiving surface tends to wear will also generate | occur | produce. Further, in the shake correction device, the clamping force for clamping the rolling member is determined by the attractive force between the driving magnet of the linear motor for driving the movable part and the coil yoke arranged on the back side of the driving coil. Is generated. Here, the magnetic force of the driving magnet is set so as to obtain an appropriate driving force as a linear motor. For this reason, the attraction force acting between the driving magnet and the coil yoke becomes larger than necessary as the clamping force for clamping the rolling member, and there is a problem that the receiving surface is easily worn.

Therefore, the present invention provides an actuator capable of suppressing the rotational movement of the movable part while allowing the translational movement of the movable part by rolling of the rolling member, and a lens unit and a camera including the actuator. It is aimed.
Another object of the present invention is to provide an actuator that can suppress wear on the receiving surface even when the holding force for holding the rolling member is large, and a lens unit and a camera including the actuator. .

  In order to solve the above-described problem, the present invention is an actuator for moving an imaging lens in a plane orthogonal to the optical axis thereof to prevent image blur, and includes a fixed portion, an intermediate support portion, The first rolling that is sandwiched between the fixed portion and the intermediate support portion and supports the intermediate support portion with respect to the fixed portion so that the intermediate support portion is moved in a first direction within a plane orthogonal to the optical axis. A member, a movable part to which an imaging lens is attached, and an intermediate support part and the movable part. The movable part moves in a second direction different from the first direction in a plane orthogonal to the optical axis. As described above, the second rolling member that supports the movable portion with respect to the intermediate support portion, and drive means that drives the movable portion relative to the fixed portion are characterized.

  In the present invention configured as described above, the movable portion to which the imaging lens is attached is supported with respect to the intermediate support portion by the second rolling member. The intermediate support part is supported with respect to the fixed part by the first rolling member. The first rolling member supports the intermediate support portion so as to be movable in the first direction, and the second rolling member supports the movable portion so as to be movable in the second direction. The driving means drives the movable part relative to the fixed part to move the imaging lens.

  According to the present invention configured as described above, the first rolling member and the second rolling member roll to suppress the rotational movement of the movable part while allowing the movable part to translate in any direction. can do.

  In the present invention, preferably, the fixed portion and the intermediate support portion are formed with first guide grooves, which receive the first rolling member and guide the first rolling member, on their opposing surfaces, respectively. The support part and the movable part are each formed with a second guide groove for receiving the second rolling member and guiding the second rolling member on their opposing surfaces.

  According to the present invention configured as described above, the first and second guide grooves guide the rolling of the first and second rolling members in the first direction and the second direction, respectively. The rotational movement of the part can be further suppressed.

In the present invention, preferably, the first rolling member or the second rolling member is a substantially cylindrical roller.
According to the present invention configured as described above, the first rolling member or the second rolling member is in line contact with the fixed portion, the intermediate support portion, and the movable portion. Wear can be suppressed.

  In the present invention, it is preferable that the first rolling member is a plurality of substantially spherical balls, and the first guide grooves for receiving the balls extend in the first direction to move the intermediate support portion relative to the fixed portion. The second rolling member is a plurality of substantially spherical balls, and the second guide grooves for receiving the balls respectively extend in the second direction and are formed on the movable portion. It is comprised so that the movement with respect to an intermediate | middle support part may be controlled only to a 2nd direction.

  According to the present invention configured as described above, since the movement of the ball is regulated by the first or second guide groove, the movement direction of the intermediate support unit or the movable unit is regulated while being supported by the spherical ball. be able to.

  In the present invention, preferably, at least three sets of the first guide grooves are provided, and at least two of them are arranged substantially in a straight line in the first direction to move the intermediate support portion relative to the fixed portion. And the other first guide grooves are configured to allow movement of the ball in directions other than the first direction, or at least three sets of the second guide grooves are provided. , And at least two of these are arranged substantially in a straight line in the second direction and configured to restrict movement of the movable part relative to the intermediate support part only in the second direction, and the other second The guide groove is configured to allow movement of the ball in a direction other than the second direction.

  According to the present invention thus configured, the position of the guide groove can be adjusted while strictly restricting the moving direction of the intermediate support portion or the movable portion by at least two sets of the guide grooves arranged substantially in a straight line. Manufacturing errors can be absorbed. Thereby, the parallelism of an intermediate | middle support part or a movable part can be maintained, enabling the exact | strict regulation of the moving direction of an intermediate | middle support part or a movable part.

  In the present invention, preferably, the first guide groove or the second guide groove is formed such that at least a part of the cross section thereof has a radius of curvature of 53 to 56 percent of the diameter of the ball.

  According to the present invention configured as described above, when the balls are pressed against the guide grooves and they are slightly elastically deformed, the contact area between the two can be widened. However, wear of the ball and the guide groove can be suppressed.

  In the present invention, preferably, it further includes a fixed part magnetic material attached to the fixed part and a movable part magnetic material attached to the movable part, and the movable part is between the fixed part magnetic material and the movable part magnetic material. Is attracted to the fixed portion by the magnetic force acting on the.

  According to the present invention configured as described above, since the clamping force for clamping each rolling member is given by the magnetic force, it is possible to prevent the occurrence of sliding resistance due to the mechanism for imparting the clamping force. it can.

  In the present invention, it is preferable that the driving means includes a driving coil attached to the fixed portion and a driving magnet attached to the movable portion, and is further disposed on the back side of the driving coil. It has a coil yoke that sandwiches the first rolling member and the second rolling member by a magnetic force acting between the magnet and the driving magnet functions as a movable part magnetic material, and the coil yoke serves as a fixed part magnetic material. Function.

  According to the present invention configured as described above, since the driving magnet for driving the movable part can be used also as the movable part magnetic material, the actuator can be simply configured.

The lens unit of the present invention includes a lens barrel, a plurality of imaging lenses housed in the lens barrel, and an actuator of the present invention in which a part of these imaging lenses is attached to a movable part. It is characterized by having.
The camera of the present invention includes a camera body and the lens unit of the present invention.

According to the actuator of the present invention, and the lens unit and camera provided with the actuator, the rotational movement of the movable part can be suppressed while allowing the translational movement of the movable part by rolling the rolling member.
In addition, according to the actuator of the present invention, and the lens unit and camera including the actuator, wear of the receiving surface can be suppressed even when the holding force for holding the rolling member is large.

Next, a camera according to an embodiment of the present invention will be described with reference to the accompanying drawings.
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 is attached to the camera body 4 and configured to form incident light on the film surface F. The lens unit 2 includes a lens barrel 6, a plurality of imaging lenses 8 arranged in the lens barrel, and an image blur correction lens 16 that is one of these imaging lenses. The actuator 10 is moved within a predetermined plane, and gyros 34a and 34b (only 34a is shown in FIG. 1) which are vibration detecting means for detecting the vibration of the lens barrel 6. 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 camera 1 according to the present embodiment detects vibrations by the gyros 34 a and 34 b, operates the actuator 10 based on the detected vibrations to move the image blur correction lens 16, and moves it to the film surface F in the camera body 4. It stabilizes the focused image. In the present embodiment, piezoelectric vibration gyros are used as the gyros 34a and 34b. In the present embodiment, the image blur correction 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 correction 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 an exploded perspective view of the actuator 10, FIG. 3 is a sectional view taken along line III-III in FIG. 2, and FIG. 4 is a sectional view taken along line IV-IV in FIG. 5A is a cross-sectional view taken along the line V-V in FIG. 2, and FIG. 5B is a diagram showing the positional relationship between the driving coil and the driving magnet.
The actuator 10 moves the moving frame 14 in a plane parallel to the film surface F with respect to the fixed frame 12 fixed to the lens barrel 6, whereby the image blur correction 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.

  As shown in FIGS. 2 to 5, the actuator 10 includes a fixed frame 12 that is a fixed portion fixed in the lens barrel 6, and an intermediate support portion that is movably supported with respect to the fixed frame 12. A support frame 13 and a moving frame 14 which is a movable part supported to be movable with respect to the intermediate support frame 13 are provided. Three first rollers 18a, 18b, 18c, which are first rolling members, are arranged between the fixed frame 12 and the intermediate support frame 13, and the intermediate support frame 13 with respect to the fixed frame 12 in the first direction D1. It is movably supported. Further, three second rollers 19 a, 19 b, 19 c, which are second rolling members, are arranged between the intermediate support frame 13 and the moving frame 14, and the moving frame 14 is first with respect to the intermediate support frame 13. It is movably supported in a second direction D2 different from the direction. In the present embodiment, the first direction D1 in which the intermediate support frame 13 is moved is directed in the vertical direction, and the second direction D2 in which the movable frame 14 is moved is directed in the horizontal direction.

  Further, the actuator 10 is a movable part magnetic material 2 attached to positions corresponding to the two driving coils 20a and 20b attached to the fixed frame 12 and the driving coils 20a and 20b of the moving frame 14, respectively. It has two drive magnets 22a and 22b and magnetic sensors 24a and 24b which are position detection means arranged inside each drive coil 20a and 20b. The actuator 10 also has a coil yoke 26 that is a fixed portion magnetic material attached to the fixed frame 12 in order to attract the moving frame 14 to the fixed frame 12 by the magnetic force of the drive magnets 22a and 22b. The drive coils 20a and 20b and the drive magnets 22a and 22b attached to the corresponding positions constitute drive means.

  Further, as shown in FIG. 1, the actuator 10 is configured so that each of the driving coils 20a and 20b is based on the vibration detected by the gyros 34a and 34b and the positional information of the moving frame 14 detected by the magnetic sensors 24a and 24b. And a controller 36 which is a control means for controlling the current to be passed through.

  The fixed frame 12 has a substantially square plate shape, and a circular opening 12a is formed at the center thereof. Further, two drive coils 20a and 20b are arranged near the midpoints of adjacent sides of the fixed frame 12, respectively. That is, these two drive coils 20a and 20b are arranged on the circumference centered on the optical axis of the lens unit 2 at an interval of a central angle of 90 °. In the present embodiment, the drive coil 20a is disposed vertically below the optical axis, and the drive coil 20b is disposed in the horizontal direction with respect to the optical axis. In addition, each of the drive coils 20a and 20b is arranged such that its winding is wound in a rectangular shape with rounded corners, and the center line of this rectangle coincides with the axis extending in the radial direction from the optical axis.

  Further, the fixed frame 12 is formed with three fixed frame guide grooves 30a, 30b, and 30c, which are first guide grooves that receive the three cylindrical first rollers 18a, 18b, and 18c, respectively. These fixed frame guide grooves 30a, 30b, and 30c are respectively disposed at three corners of the fixed frame 12, and the drive coil 20b is fixed between the fixed frame guide grooves 30a and 30c. They are positioned between the frame guide grooves 30a and 30b, respectively. Each of the fixed frame guide grooves 30a, 30b, and 30c is formed as a rectangular recess, and is arranged such that the long side of the rectangle is parallel to the first direction D1.

  As shown in FIG. 4, the width of the fixed frame guide groove 30a is slightly larger than the width of the first roller 18a. For this reason, the 1st roller 18a is guided by the fixed frame guide groove 30a, and is arrange | positioned so that rolling is possible only to the 1st direction D1. The other fixed frame guide grooves 30b and 30c are also formed in the same manner as the fixed frame guide groove 30a, and the first rollers 18b and 18c are arranged to roll only in the first direction D1.

  The intermediate support frame 13 is a substantially inverted L-shaped member, and is disposed between the fixed frame 12 and the moving frame 14 in parallel therewith. Further, the intermediate support frame 13 is supported by sandwiching the first rollers 18a, 18b, and 18c between the fixed frame 12, and the first direction D1 with respect to the fixed frame 12 in a plane orthogonal to the optical axis. Configured to be moved to.

  Further, on the surface of the intermediate support frame 13 that faces the fixed frame 12, three intermediate support frame first guide grooves 31a, 31b, which are first guide grooves that receive the three first rollers 18a, 18b, 18c, respectively, 31c is formed. Each intermediate support frame first guide groove 31a, 31b, 31c is formed as a rectangular recess, and is arranged so that the long side of the rectangle is parallel to the first direction D1. The intermediate support frame first guide grooves 31a, 31b, and 31c are formed at positions corresponding to the fixed frame guide grooves 30a, 30b, and 30c of the fixed frame 12, respectively. That is, intermediate support frame first guide grooves 31a are arranged at corners of the inverted L-shaped intermediate support frame 13, and intermediate support frame first guide grooves 31b and 31c are arranged at both ends.

  The width of each intermediate support frame first guide groove 31a, 31b, 31c is slightly larger than the width of the first roller 18a, 18b, 18c. For this reason, each 1st roller 18a, 18b, 18c is guided by each intermediate support frame 1st guide groove 31a, 31b, 31c, and can only roll with respect to the intermediate support frame 13 in the 1st direction D1. ing. With this configuration, the movement of the intermediate support frame 13 relative to the fixed frame 12 is restricted only in the first direction D1.

  Furthermore, three intermediate support frame second guide grooves 32a, which are second guide grooves for receiving the three cylindrical second rollers 19a, 19b, 19c, are provided on the surface of the intermediate support frame 13 that faces the moving frame 14, respectively. 32b and 32c are formed. Each of the intermediate support frame second guide grooves 32a, 32b, and 32c is formed as a rectangular recess, and is arranged such that the long side of the rectangle is parallel to the second direction D2. The intermediate support frame second guide grooves 32a, 32b, 32c are formed on the back side of the intermediate support frame first guide grooves 31a, 31b, 31c, respectively. That is, the intermediate support frame second guide grooves 32a are disposed at the corners of the inverted L-shaped intermediate support frame 13, and the intermediate support frame second guide grooves 32b and 32c are disposed at both ends.

  Further, the width of each intermediate support frame second guide groove 32a, 32b, 32c is formed slightly larger than the width of the second rollers 19a, 19b, 19c. Therefore, each of the second rollers 19a, 19b, and 19c is guided by each of the intermediate support frame second guide grooves 32a, 32b, and 32c, and can roll only in the second direction D2 with respect to the intermediate support frame 13. ing.

  Further, two rectangular openings 13a are formed in the intermediate support frame 13 between the intermediate support frame second guide grooves 32a and 32b and between the intermediate support frame second guide grooves 32a and 32c, respectively. The rectangular openings 13a are formed so that the driving coils 20a and 20b attached to the fixed frame 12 and the driving magnets 22a and 22b attached to the moving frame 14 face each other through the rectangular openings 13a. (FIG. 3). Each rectangular opening 13a is formed in such a size that the intermediate support frame 13 and each driving coil do not interfere even when the intermediate support frame 13 is moved during the image blur prevention control.

  The moving frame 14 has a substantially square plate shape and is disposed in parallel with the intermediate support frame 13. An image blur correction lens 16 is attached to the central opening of the moving frame 14. Further, the moving frame 14 is supported by sandwiching the second rollers 19a, 19b, and 19c with the intermediate support frame 13, and in the second direction with respect to the intermediate support frame 13 in a plane perpendicular to the optical axis. It is configured to be moved to D2.

  Three rectangular moving frame guide grooves 33a, 33b, and 33c, which are second guiding grooves that receive the three second rollers 19a, 19b, and 19c, are formed on the surface of the moving frame 14 that faces the intermediate support frame 13. Has been. Each moving frame guide groove 33a, 33b, 33c is formed as a rectangular recess, and is arranged such that the long side of the rectangle is parallel to the second direction D2. The moving frame guide grooves 33a, 33b, 33c are formed at positions corresponding to the intermediate support frame second guide grooves 32a, 32b, 32c, respectively.

  Furthermore, the width of each moving frame guide groove 33a, 33b, 33c is formed slightly larger than the width of the second rollers 19a, 19b, 19c. For this reason, each 2nd roller 19a, 19b, 19c is guided by each moving frame guide groove 33a, 33b, 33c, and can roll only with respect to the moving frame 14 in the 2nd direction D2. With this configuration, the movement of the moving frame 14 with respect to the intermediate support frame 13 is restricted only in the second direction D2.

  The coil yoke 26 has a rectangular shape, and is attached to the back side of the drive coils 20a and 20b, that is, to the surface of the fixed frame 12 that does not face the intermediate support frame 13, respectively. The moving frame 14 is attracted to the fixed frame 12 by the magnetic force exerted by the driving magnets 22a and 22b on the corresponding coil yokes 26 attached thereto. Due to the magnetic force acting between the drive magnet and the coil yoke, the first rollers 18a, 18b, 18c, the intermediate support frame 13, and the second rollers 19a, 19b disposed between the fixed frame 12 and the moving frame 14, 19 c is sandwiched between the fixed frame 12 and the moving frame 14. In the present embodiment, the fixed frame 12 is made of a nonmagnetic material so that the magnetic lines of force of the drive magnets 22a and 22b can reach the coil yoke 26 efficiently.

  The drive magnets 22a and 22b have a rectangular shape and are embedded in the surface of the moving frame 14 facing the intermediate support frame 13, respectively. Further, the drive magnets 22a and 22b are arranged at positions corresponding to the drive coils 20a and 20b. That is, the drive magnets 22a and 22b are arranged on the circumference centered on the optical axis of the lens unit 2 at intervals of 90 ° central angles. Further, as shown in FIG. 2, each of the driving magnets 22a and 22b is arranged such that the center line passing through the long side thereof coincides with the axis extending in the radial direction from the optical axis.

  Furthermore, as shown in FIG. 5, the drive magnet 22a is arranged so that its magnetization boundary line C faces the horizontal direction. As a result, the driving magnet 22a receives a driving force in the vertical direction (first direction D1) when a current flows through the corresponding driving coil 20a.

  In addition, in this specification, the magnetization boundary line C shall mean the line which connected the point where the polarity of each drive magnet changes. Therefore, in this embodiment, the magnetization boundary line C is located so as to pass through the midpoint of each short side of the rectangular driving magnet. Further, as shown in FIG. 5A, the polarity of the driving magnet 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, and the upper left corner. Is the N pole and the upper right is the S pole.

  Also, with respect to the other driving coil 20b, the corresponding driving magnet 22b and coil yoke 26 are arranged in the same positional relationship. As a result, the driving magnet 22b receives a driving force in the horizontal direction (second direction D2) when a current flows through the corresponding driving coil 20b.

  As described above, when a current flows through the driving coil 20a, the driving magnet 22a receives a vertical driving force, whereby the intermediate support frame 13 is moved in the first direction D1 with respect to the fixed frame 12. As a result, the moving frame 14 supported on the intermediate support frame 13 is also moved together with the intermediate support frame 13, and the image blur correction lens 16 is moved in the vertical direction. On the other hand, when a current flows through the driving coil 20b, the driving magnet 22b receives a horizontal driving force, whereby the moving frame 14 is moved in the second direction D2 with respect to the intermediate support frame 13. As a result, the image blur correction lens 16 is moved in the horizontal direction. By combining these movements in the vertical direction and the horizontal direction, the image blur correction lens 16 is translated to an arbitrary position within a plane orthogonal to the optical axis.

Next, the position detection of the moving frame 14 will be described with reference to FIGS.
FIG. 6 is a diagram for explaining the relationship between the movement of the driving magnet 22a and the signal output from the magnetic sensor 24a, and FIG. 7 is a diagram showing the positional relationship between the driving magnet and the magnetic sensor.

  As shown in FIGS. 3 and 5, magnetic sensors 24 a and 24 b are respectively arranged inside the drive coils 20 a and 20 b. Each magnetic sensor has a sensitivity center point S of each magnetic sensor when the moving frame 14 is at the center position of the image blur prevention control in which the optical axis of the image blur correction lens 16 and the optical axis of the other imaging lens 8 coincide. Are arranged on the magnetization boundary line C of each drive magnet. In the present embodiment, a Hall element is used as the magnetic sensor.

  As shown in FIG. 6, when the sensitivity center point S of the magnetic sensor 24a is located on the magnetization boundary line C of the driving magnet 22a, the output signal from the magnetic sensor 24a is zero. When the driving magnet 22a is moved together with the moving frame 14, and the sensitivity center point of the magnetic sensor 24a deviates from the magnetization boundary line of the driving magnet 22a, the output signal of the magnetic sensor 24a changes. As shown in FIG. 6, when the driving magnet 22a is moved in the direction orthogonal to the magnetization boundary line C, that is, in the Y-axis direction (vertical direction), the magnetic sensor 24a generates a sinusoidal signal. To do. 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 22a. In the present embodiment, when the moving distance of the driving magnet 22a is within about 3% of the length of the short side of the driving magnet 22a, 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 magnetization boundary line C of the driving magnet 22a. 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 7D, when the magnetization boundary C of the driving magnet 22a is positioned on the sensitivity center point S of the magnetic sensor 24a, the driving is performed as shown in FIG. 7B. Even if the magnet 22a is moved in the direction of the magnetization boundary C, the output signal from the magnetic sensor 24a remains zero. Further, as shown in FIGS. 7C and 7D, when the magnetization boundary line C of the driving magnet 22a deviates from the sensitivity center point S of the magnetic sensor 24a, the sensitivity center point S and the magnetization boundary line are separated. A signal proportional to the distance r between the lines C is output from the magnetic sensor 24a. Therefore, if the distance r between the sensitivity center point S and the magnetization boundary line C is the same, the driving magnet 22a is moved in a direction perpendicular to the magnetization boundary line C as shown in FIG. As shown in FIG. 7D, even when the drive magnet 22a is translated in any direction, a signal having the same magnitude is output from the magnetic sensor 24a.

  Although the magnetic sensor 24a has been described here, the other magnetic sensor 24b also outputs a similar signal based on the positional relationship with the corresponding driving magnet 22b. That is, the magnetic sensor 24b generates a signal when the driving magnet 22b is moved in the horizontal direction. For this reason, the position where the moving frame 14 is translated relative to the fixed frame 12 can be specified based on the signals detected by the magnetic sensors 24a and 24b.

  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 velocity of the pitching motion of the lens unit 2, and the gyro 34b is configured to detect the angular velocity of the yawing motion.

  The arithmetic circuits 38a and 38b generate lens position command signals for instructing in time series the position to which the image blur correction lens 16 should be moved, based on the angular velocities input from the gyros 34a and 34b every moment. That is, the arithmetic circuit 38a time-integrates the angular velocity of the pitching motion detected by the gyro 34a and adds a predetermined correction signal to generate a vertical component of the lens position command signal. Similarly, the arithmetic circuit 38b The horizontal component of the lens position command signal is generated based on the angular velocity of the yawing motion detected by the gyro 34b. Even if the lens unit 2 vibrates during exposure for photography by moving the image blur correction 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.

  On the other hand, the amount of movement of the driving magnet 22a 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 vertical component of the lens position command signal output from the arithmetic circuit 38a and the amount of movement of the driving magnet 22a relative to the driving coil 20a output from the magnetic sensor amplifier 42a. It flows in the driving coil 20a. Accordingly, when there is no difference between the lens 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 22a becomes zero.

  Similarly, the amount of movement of the driving magnet 22b 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 horizontal component of the lens position command signal output from the arithmetic circuit 38b and the amount of movement of the driving magnet 22b 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 lens 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 22b becomes zero.

Next, an example of a specific circuit of the controller 36 will be described with reference to FIG. FIG. 9 shows an example of a circuit that controls the current flowing through the driving coil 20a. In the circuit of FIG. 9, ancillary circuits such as a power supply line for operating each operational amplifier are omitted. First, as shown in FIG. 9, 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 lens 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 functions as a buffer amplifier for the lens 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. Therefore, the difference between the output of the magnetic sensor 24a and the lens 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, causing a magnetic force to act on the driving magnet 22a and moving the driving magnet 22a. This magnetic force acts in a direction in which the driving magnet 22a approaches the position commanded by the coil position command signal. When the driving magnet 22a is moved, the voltage output from the fourth terminal of the magnetic sensor 24a changes. When the driving magnet 22a moves to the position commanded by the lens 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. 9 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. 9, the current flowing through the driving coil 20b can also be controlled by the same circuit.

  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 velocity signal in the pitching direction of the lens unit 2 to the arithmetic circuit 38a, and the gyro 34b outputs an angular velocity signal in the yawing direction to the arithmetic circuit 38b. The arithmetic circuit 38a integrates the input angular velocity signal with 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. Similarly, the arithmetic circuit 38b integrates the input angular velocity signal with time to calculate the yawing angle, and adds a predetermined correction signal to this to generate a horizontal lens position command signal. An image focused on the film surface F of the camera body 4 by moving the image blur correction lens 16 momentarily to a position commanded by a lens position command signal output in time series by the arithmetic circuits 38a and 38b. Is stabilized.

The lens position command signal r _Y in the vertical direction output from the arithmetic circuit 38a is input to the differential circuit 44a. Similarly, the lens position command signal r _X horizontal output by the arithmetic circuit 38b is input to the differential circuit 44b.

  On the other hand, the magnetic sensor 24a arranged inside the driving coil 20a outputs a detection signal to the magnetic sensor amplifier 42a, and the magnetic sensor 24b inside the driving coil 20b outputs a detection signal to the magnetic sensor amplifier 42b. The detection signals of the magnetic sensors amplified by the magnetic sensor amplifiers 42a and 42b are input to the differential circuits 44a and 44b, respectively.

Differential circuit 44a, 44b includes a detection signal of the magnetic sensors and the lens position command signal r _X, r voltage respectively to generate in accordance with the difference in _Y, the coil 20a for driving a current proportional to the voltage , 20b. 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 disposed corresponding to each driving coil receives a driving force in a direction approaching the position specified by the lens position command signals r _X and r _Y.

  When the driving magnet 22a receives a driving force in the vertical direction, the first rollers 18a, 18b, 18c sandwiched between the fixed frame 12 and the intermediate support frame 13 are fixed frame guide grooves 30a, 30b, 30c and It is rolled in the vertical direction (first direction D1) while being guided by the intermediate support frame first guide grooves 31a, 31b, 31c. Accordingly, the intermediate support frame 13 is moved in the vertical direction with respect to the fixed frame 12, and the moving frame 14 is also translated in the vertical direction together with the intermediate support frame 13. At this time, since each first roller is rolled inside the fixed frame guide groove and the intermediate support frame first guide groove, the resistance to movement of the moving frame 14 is only rolling resistance, and sliding resistance does not act. Therefore, the moving frame 14 is smoothly moved with a small driving force. Moreover, since the 1st roller, the fixed frame 12, and the intermediate | middle support frame 13 are comprised with the material with high surface hardness, the rolling resistance of a 1st roller becomes especially small.

  On the other hand, when the driving magnet 22b receives a driving force in the horizontal direction, the second rollers 19a, 19b, 19c sandwiched between the moving frame 14 and the intermediate support frame 13 are moved to the moving frame guide grooves 33a, 33b, 33c and the intermediate support frame second guide grooves 32a, 32b, and 32c are rolled in the horizontal direction (second direction D2) while being guided. Thereby, the moving frame 14 is translated in the horizontal direction with respect to the intermediate support frame 13. At this time, since each second roller is rolled inside the moving frame guide groove and the intermediate support frame second guide groove, the resistance to the movement of the moving frame 14 is only rolling resistance, and no sliding resistance acts. Therefore, the moving frame 14 is smoothly moved with a small driving force. Moreover, since the 2nd roller, the moving frame 14, and the intermediate | middle support frame 13 are comprised with the material with high surface hardness, the rolling resistance of a 2nd roller becomes especially small.

  Further, the movement of the intermediate support frame 13 relative to the fixed frame 12 is restricted only in the vertical direction by the fixed frame guide grooves 30a, 30b, 30c and the intermediate support frame first guide grooves 31a, 31b, 31c. Since the movement with respect to the support frame 13 is restricted only in the horizontal direction by the movement frame guide grooves 33a, 33b, 33c and the intermediate support frame second guide grooves 32a, 32b, 32c, the rotation movement of the movement frame 14 is prevented. The

  Furthermore, since the first and second rollers and each guide groove are in line contact, the contact area is larger than when the ball rolls on a plane, and acts on the first and second rollers and each guide groove. The contact pressure is reduced.

  When the driving magnet reaches the position specified by the lens position command signal by the driving force acting between each driving coil and the driving magnet, the lens position command signal and the detection signal of the magnetic sensor coincide with each other. The output of the circuit is 0 and the driving force is also 0. In addition, when each driving magnet deviates from 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 passed to each driving coil, and each driving magnet is The position is returned to the position specified by the position command signal.

  By repeating the above operation every moment, the image blur correction lens 16 attached to the moving frame 14 having each driving magnet 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.

  According to the camera of the first embodiment of the present invention, the moving frame is moved by rolling the first roller and the second roller, so that the sliding resistance acting on the moving frame can be suppressed. Rotational movement of the moving frame can be suppressed while allowing translational movement of the moving frame in any direction.

  Further, according to the camera of the present embodiment, the rolling of each roller is guided in the first direction and the second direction by each guide groove, so that the rotational movement of the moving frame can be effectively suppressed. it can.

  Furthermore, according to the camera of this embodiment, since each roller is in line contact with each guide groove, a large contact area between them can be ensured. Thereby, even when a large attractive force acts between the driving magnet and the coil yoke, wear of each roller and each guide groove can be suppressed. That is, when the magnetic force of the driving magnet is set so that an appropriate driving force can be generated between the driving magnet and the attraction force acting between the driving magnet and the coil yoke is excessive. Moreover, wear of each roller and each guide groove can be suppressed.

  Further, according to the camera of the present embodiment, the clamping force for clamping each roller is given by the magnetic force, so that the clamping force is greater than when the moving frame is attracted to the fixed frame by an elastic body or the like, or compared to when pressed. The sliding resistance resulting from the mechanism for providing can be reduced.

  Furthermore, according to the camera of this embodiment, the driving magnet for driving the moving frame can be used also as the movable part magnetic material for generating the clamping force, so that the actuator is simply configured. Can do.

  Moreover, in the camera of 1st Embodiment of this invention mentioned above, although the 1st roller and the 2nd roller were guided by each guide groove, a part or all of a guide groove can also be abbreviate | omitted. In other words, the cylindrical roller is easily moved in the rolling direction (direction perpendicular to the central axis of the cylindrical shape), but is difficult to move because sliding resistance is generated in other directions. is there. For this reason, even when the guide groove is omitted, the intermediate support frame and the moving frame supported by the roller are supported so as to be movable substantially only in the direction in which the roller can roll. Accordingly, the intermediate support frame is supported so as to be moved in the first direction D1 with respect to the fixed frame, and the movable frame is supported so as to be moved in the second direction D2 with respect to the intermediate support frame. become.

  Moreover, although the 1st roller and the 2nd roller were each comprised by the cylindrical shape, the shape of a roller can also be made into a barrel shape etc.

  Next, a camera according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 10 is an exploded perspective view of an actuator used in the camera of this embodiment. 11 is a cross-sectional view taken along line XI-XI in FIG. 10, and FIG. 12 is a cross-sectional view taken along line XII-XII in FIG.

  The camera of this embodiment is different from the first embodiment described above in terms of the support mechanism for the intermediate support frame and the moving frame of the actuator used in the camera. Accordingly, here, only the points of the present embodiment that are different from the first embodiment will be described, and the same components will be denoted by the same reference numerals and the description thereof will be omitted.

  As shown in FIG. 10, the actuator 110 includes a fixed frame 112 that is a fixed portion fixed in the lens barrel 6, and an intermediate support frame 113 that is an intermediate support portion that is movably supported with respect to the fixed frame 112. , And a moving frame 114 that is a movable part supported so as to be movable with respect to the intermediate support frame 113. Between the fixed frame 112 and the intermediate support frame 113, three first balls 118a, 118b, and 118c, which are first rolling members, are arranged, and the intermediate support frame 113 is in the first direction D1 with respect to the fixed frame 112. It is movably supported. Further, three second balls 119 a, 119 b, and 119 c that are second rolling members are disposed between the intermediate support frame 113 and the moving frame 114, and the moving frame 114 is positioned with respect to the intermediate support frame 113 in a first manner. It is movably supported in a second direction D2 different from the direction D1. In the present embodiment, the first direction D1 in which the intermediate support frame 113 is moved is directed in the vertical direction, and the second direction D2 in which the movable frame 114 is moved is directed in the horizontal direction.

  Furthermore, the actuator 110 includes two drive coils 20a and 20b, two drive magnets 22a and 22b that are movable part magnetic materials, and magnetic sensors 24a and 24b. The actuator 110 has a coil yoke 26 that is a fixed portion magnetic material attached to the fixed frame 112.

The fixed frame 112 has a substantially square plate shape, and two driving coils 20a and 20b are arranged near the midpoints of the adjacent sides.
Further, the fixed frame 112 is formed with three fixed frame guide grooves 130a, 130b, and 130c, which are first guide grooves that receive the three spherical first balls 118a, 118b, and 118c, respectively. Each fixed frame guide groove 130 a, 130 b, 130 c is disposed at each of the three corners of the fixed frame 112.

  Of these fixed frame guide grooves, the two fixed frame guide grooves 130a and 130b arranged on both sides of the drive coil 20b are formed to extend on one straight line directed in the first direction D1. ing. Further, as shown in FIG. 11, the fixed frame guide grooves 130a and 130b have an arcuate cross-sectional shape (the fixed frame guide grooves 130a are shown in FIG. 11). Therefore, the first balls 118a and 118b sandwiched between the fixed frame 112 and the intermediate support frame 113 and received in the fixed frame guide grooves 130a and 130b have high accuracy on a straight line directed in the first direction D1. And the movement is restricted so as to roll only in the first direction D1.

  In the present embodiment, the fixed frame guide grooves 130a and 130b are formed such that the radius of curvature Rs of the cross-sectional curve thereof is about 55% of the diameter D of the first balls 118a and 118b. Preferably, the radius of curvature Rs of the cross-sectional curve of the fixed frame guide groove is about 53 to 56 percent of the diameter D of the receiving ball. Thereby, when the surface of the guide groove and the ball are slightly elastically deformed, the contact area between the guide groove and the ball can be enlarged, and the surface pressure acting on the surface of the guide groove and the ball can be reduced. .

  On the other hand, the fixed frame guide groove 130c is formed so as to extend in the first direction D1, but as shown in FIG. 12, the bottom thereof is formed flat. Therefore, the first ball 118c received in the fixed frame guide groove 130c is allowed to move in directions other than the first direction D1.

  Here, the contact area between the surface of the fixed frame guide groove 130c and the first ball 118c is smaller than the contact area in the other two fixed frame guide grooves because the bottom of the fixed frame guide groove 130c is formed flat. Become. However, since the fixed frame guide groove 130c is disposed at a position away from the gravity center G (FIG. 10) of the attractive force for holding the first ball, the pressing force for pressing the first ball 118c against the fixed frame guide groove 130c is Relatively small. For this reason, an excessive surface pressure does not act on the fixed frame guide groove 130c and the first ball 118c.

  The gravity center G of the attracting force refers to the moment of force due to the attracting force acting between the driving magnet 22 a and the coil yoke 26 and the moment of force due to the attracting force acting between the driving magnet 22 b and the coil yoke 26. Means a balanced point. In this embodiment, since each attracting force is equal, the center of gravity of the attracting force is located at the midpoint of the line segment connecting the center point of the drive magnet 22a and the center point of the drive magnet 22b.

  The intermediate support frame 113 is a substantially inverted L-shaped member, and is disposed between the fixed frame 112 and the moving frame 114 in parallel therewith. Further, the intermediate support frame 113 is supported by sandwiching the first balls 118a, 118b, and 118c with the fixed frame 112, and the first direction D1 with respect to the fixed frame 112 in a plane orthogonal to the optical axis. Configured to be moved to.

  Further, on the surface of the intermediate support frame 113 that faces the fixed frame 112, three intermediate support frame first guide grooves 131a, 131b, which are first guide grooves that receive the three first balls 118a, 118b, 118c, respectively. 131c is formed. Further, the intermediate support frame first guide grooves 131a, 131b, 131c are formed at positions corresponding to the fixed frame guide grooves 130a, 130b, 130c of the fixed frame 112, respectively. That is, intermediate support frame first guide grooves 131a are arranged at corners of the inverted L-shaped intermediate support frame 113, and intermediate support frame first guide grooves 131b and 131c are arranged at both ends.

  Of these intermediate support frame first guide grooves, two intermediate support frame first guide groove grooves 131a and 131b arranged corresponding to the fixed frame guide grooves 130a and 130b are oriented in the first direction D1. It is formed so as to extend on one straight line. Further, the cross-sectional shape of the intermediate support frame first guide groove grooves 131a and 131b is configured similarly to the fixed frame guide grooves 130a and 130b (FIG. 11). For this reason, the first balls 118a and 118b received in the intermediate support frame first guide groove grooves 131a and 131b are positioned with high accuracy on a straight line directed in the first direction D1, and in the first direction. The movement is restricted so that only D1 rolls. With this configuration, the movement of the intermediate support frame 113 with respect to the fixed frame 112 is restricted only in the first direction D1 with high accuracy.

  On the other hand, the intermediate support frame first guide groove 131c is formed so as to extend in the first direction D1, but has the same cross-sectional shape as the fixed frame guide groove 130c (FIG. 12). Therefore, the first ball 118c received in the intermediate support frame first guide groove 131c is allowed to move in directions other than the first direction D1. With this configuration, even when a manufacturing error is included in the position of the intermediate support frame first guide groove 131c, this error can be absorbed, and the parallelism between the fixed frame 112 and the intermediate support frame 113 is maintained. It becomes possible to do. That is, when the fixed frame guide groove 130c and the intermediate support frame first guide groove 131c are formed in a shape that does not allow movement of the first ball other than in the first direction D1, the intermediate support frame first guide groove If there is a manufacturing error in the distance between 131c and the intermediate support frame first guide groove 131a, etc., each first ball cannot be positioned at the same position in each guide groove, so that the intermediate support frame 113 is fixed to the fixed frame 112. And the parallelism between them cannot be maintained.

  Further, on the surface of the intermediate support frame 113 that faces the moving frame 114, three intermediate support frame second guide grooves 132a, which are second guide grooves that receive the three spherical second balls 119a, 119b, and 119c, respectively. 132b and 132c are formed. Each intermediate support frame second guide groove 132a, 132b, 132c is formed on the back side of the intermediate support frame first guide groove 131a, 131b, 131c, respectively. That is, the intermediate support frame second guide grooves 132a are disposed at the corners of the inverted L-shaped intermediate support frame 113, and the intermediate support frame second guide grooves 132b and 132c are disposed at both ends.

  Of these intermediate support frame second guide grooves, the two intermediate support frame second guide grooves 132a and 132c are formed so as to extend on one straight line directed in the second direction D2. Further, the cross-sectional shape of the intermediate support frame second guide grooves 132a and 132c is configured in the same manner as the fixed frame guide grooves 130a and 130b (FIG. 11). For this reason, the second balls 119a and 119c received in the intermediate support frame second guide grooves 132a and 132c are positioned with high accuracy on a straight line directed in the second direction D2, and also in the second direction D2. The movement is restricted so that it can only roll.

  On the other hand, the intermediate support frame second guide groove 132b is formed so as to extend in the second direction D2, but has a cross-sectional shape similar to that of the fixed frame guide groove 130c (FIG. 12). For this reason, the second ball 119b received in the intermediate support frame second guide groove 132b is allowed to move in directions other than the second direction D2.

  The moving frame 114 has a substantially square plate shape and is disposed in parallel with the intermediate support frame 113. An image blur correction lens 16 is attached to the central opening of the moving frame 114. Further, the moving frame 114 is supported by sandwiching the second balls 119a, 119b, and 119c between the intermediate support frame 113 and the second direction with respect to the intermediate support frame 113 in a plane orthogonal to the optical axis. It is configured to be moved to D2.

  Three moving frame guide grooves 133a, 133b, and 133c, which are second guide grooves for receiving the three second balls 119a, 119b, and 119c, are formed on the surface of the moving frame 114 that faces the intermediate support frame 113, respectively. Yes. The moving frame guide grooves 133a, 133b, and 133c are formed at positions corresponding to the intermediate support frame second guide grooves 132a, 132b, and 132c, respectively.

  Among these moving frame guide grooves, the two moving frame guide grooves 133a and 133c arranged corresponding to the intermediate support frame second guide grooves 132a and 132c are one straight line directed in the second direction D2. It is formed to extend upward. Further, the cross-sectional shapes of the moving frame guide grooves 133a and 133c are configured similarly to the fixed frame guide grooves 130a and 130b (FIG. 11). For this reason, the second balls 119a and 119b received in the moving frame guide grooves 133a and 133c are positioned with high accuracy on a straight line directed in the second direction D2 and rolled only in the second direction D2. The movement is restricted so as to be moved. With this configuration, the movement of the moving frame 114 relative to the intermediate support frame 113 is restricted only in the second direction D2 with high accuracy.

  On the other hand, the moving frame guide groove 133b is formed so as to extend in the second direction D2, but has the same cross-sectional shape as the fixed frame guide groove 130c (FIG. 12). Therefore, the second ball 119b received in the moving frame guide groove 133b is allowed to move in directions other than the second direction D2. With this configuration, even when a manufacturing error is included in the position of the moving frame guide groove 133b, this error can be absorbed, and the parallelism between the moving frame 114 and the intermediate support frame 113 can be maintained. It becomes possible.

  In the present embodiment, in the actuator 110, when a current flows through the driving coil 20a, the driving magnet 22a receives a driving force in the vertical direction, whereby the intermediate support frame 113 is moved in the first direction D1 with respect to the fixed frame 112. It is configured to be moved. As a result, the moving frame 114 supported on the intermediate support frame 113 is also moved together with the intermediate support frame 113, and the image blur correction lens 16 is moved in the vertical direction. On the other hand, when a current flows through the driving coil 20b, the driving magnet 22b receives a driving force in the horizontal direction, whereby the moving frame 114 is moved in the second direction D2 with respect to the intermediate support frame 113. As a result, the image blur correction lens 16 is moved in the horizontal direction. By combining these movements in the vertical direction and the horizontal direction, the image blur correction lens 16 is translated to an arbitrary position within a plane orthogonal to the optical axis.

  According to the camera of the second embodiment of the present invention, the movement of the ball is regulated in the first direction and the second direction by the respective guide grooves, so that while using the spherical ball as the rolling member, The moving direction of the support frame and the moving frame can be restricted.

  Further, according to the camera of the present embodiment, the moving direction of the intermediate support frame is set to the first direction by two sets arranged on a straight line among the three sets of guide grooves formed on the fixed frame and the intermediate support frame. While strictly restricting, the other set of guide grooves is configured to allow movement of the first ball in directions other than the first direction. As a result, even if there is a manufacturing error in the position of each guide groove, it can be absorbed, so that the intermediate support frame can be prevented from floating from the fixed frame due to a manufacturing error or the like. It can be supported in parallel. Similarly, according to the camera of this embodiment, the moving direction of the moving frame is changed to the second direction by two sets arranged on a straight line among the three sets of guide grooves formed on the intermediate support frame and the moving frame. The other set of guide grooves are configured to strictly regulate and allow movement of the second ball in directions other than the second direction, so that the moving frame can be supported in parallel.

  Further, according to the camera of the present embodiment, since the cross section of the guide groove is formed so as to have a curvature radius of about 55% of the diameter of the ball, the ball is pressed against the guide groove and they are slightly elastic. When deformed, the contact area between the two becomes wider than when the ball is pressed against a flat surface. Thereby, abrasion of a ball | bowl and a guide groove can be suppressed, using a ball | bowl as a rolling member.

  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 film camera. However, the present invention can be applied to any camera for capturing a still image or a moving image, 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.

  In the above-described embodiment, the intermediate support frame and the moving frame are each supported by three rolling members, but may be supported by four or more rolling members.

  Furthermore, in the first embodiment described above, the intermediate support frame and the moving frame are supported by rollers, and in the second embodiment, they are supported by balls. However, support by rollers and support by balls may be mixed. For example, the intermediate support frame can be supported by a roller and the moving frame can be supported by a ball.

It is sectional drawing of the camera by 1st Embodiment of this invention. It is a disassembled perspective view of the actuator built in the camera by 1st Embodiment of this invention. It is sectional drawing which follows the III-III line of FIG. It is sectional drawing which follows the IV-IV line of FIG. (A) Sectional drawing which follows the VV line | wire of FIG. 2, (b) It is a figure which shows the positional relationship of the drive coil and the drive magnet. It is a figure explaining the relationship between the movement of a drive magnet, and the signal output from a magnetic sensor. It is a figure which shows the positional relationship of the magnet for a drive, and a magnetic sensor. It is a block diagram which shows the signal processing in a controller. It is a figure which shows an example of the circuit which controls the electric current sent through a drive coil. It is a disassembled perspective view of the actuator currently used for the camera of 2nd Embodiment of this invention. It is sectional drawing which follows the XI-XI line of FIG. It is sectional drawing which follows the XII-XII line | wire of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera by 1st Embodiment of this invention 2 Lens unit 4 Camera main body 6 Lens barrel 8 Imaging lens 10 Actuator 12 Fixed frame (fixed part)
12a Opening 13 Intermediate support frame (intermediate support part)
13a Rectangular opening 14 Moving frame (movable part)
16 Image blur correction lens 18a, 18b, 18c First roller (first rolling member)
19a, 19b, 19c Second roller (second rolling member)
20a Driving coil 20b Driving coil 22a Driving magnet (movable magnetic material)
22b Driving magnet (movable part magnetic material)
24a Magnetic sensor 24b Magnetic sensor 26 Coil yoke (fixed part magnetic material)
30a, 30b, 30c Fixed frame guide groove (first guide groove)
31a, 31b, 31c Intermediate support frame first guide groove (first guide groove)
32a, 32b, 32c Intermediate support frame second guide groove (second guide groove)
33a, 33b, 33c Moving frame guide groove (second guide groove)
34a Gyro 34b Gyro 36 Controller 38a Arithmetic circuit 38b Arithmetic circuit 42a Magnetic sensor amplifier 42b Magnetic sensor amplifier 44a Differential circuit 44b Differential circuit 110 Actuator built in the camera according to the second embodiment of the present invention 112 Fixed frame (fixed portion) )
113 Intermediate support frame (intermediate support part)
114 Moving frame (movable part)
118a, 118b, 118c First ball (first rolling member)
119a, 119b, 119c Second ball (second rolling member)
130a, 130b, 130c Fixed frame guide groove (first guide groove)
131a, 131b, 131c Intermediate support frame first guide groove (first guide groove)
132a, 132b, 132c Intermediate support frame second guide groove (second guide groove)
133a, 133b, 133c Moving frame guide groove (second guide groove)

Claims (10)

An actuator for moving an imaging lens within a plane perpendicular to the optical axis to prevent image blur;
A fixed part;
An intermediate support,
The intermediate support portion is sandwiched between the fixed portion and the intermediate support portion, and the intermediate support portion is moved with respect to the fixed portion so that the intermediate support portion is moved in a first direction within a plane perpendicular to the optical axis. A first rolling member to be supported;
A movable part to which the imaging lens is attached;
The intermediate support unit is sandwiched between the intermediate support unit and the movable unit, and the movable unit is moved in a second direction different from the first direction in a plane orthogonal to the optical axis. A second rolling member that supports the movable part with respect to
Driving means for driving the movable part relative to the fixed part;
An actuator comprising:   Each of the fixed portion and the intermediate support portion has a first guide groove formed on the opposing surface for receiving the first rolling member and guiding the first rolling member. 2. The actuator according to claim 1, wherein each of the movable parts has a second guide groove formed on each of the opposed surfaces thereof for receiving the second rolling member and guiding the second rolling member.   The actuator according to claim 1 or 2, wherein the first rolling member or the second rolling member is a substantially cylindrical roller.   The first rolling member is a plurality of substantially spherical balls, and the first guide grooves for receiving the balls extend in the first direction to move the intermediate support portion relative to the fixed portion. Or the second rolling member is a plurality of substantially spherical balls, and the second guide grooves for receiving the balls extend in the second direction and are The actuator according to claim 2, wherein movement of the movable portion relative to the intermediate support portion is restricted only in the second direction.   At least three sets of the first guide grooves are provided, and at least two of them are arranged substantially in a straight line in the first direction to move the intermediate support portion relative to the fixed portion in the first direction. And the other first guide grooves are configured to allow movement of the ball in directions other than the first direction, or at least three sets of the second guide grooves are provided. And at least two of these are arranged substantially in a straight line in the second direction and are configured to restrict movement of the movable part relative to the intermediate support part only in the second direction. 5. The actuator according to claim 4, wherein the other second guide groove is configured to allow movement of the ball in a direction other than the second direction.   6. The actuator according to claim 4, wherein the first guide groove or the second guide groove is formed so that at least a part of a cross section thereof has a radius of curvature of 53 to 56 percent of the diameter of the ball. .   And a movable part magnetic material attached to the movable part, and the movable part acts between the fixed part magnetic material and the movable part magnetic material. The actuator according to claim 1, wherein the actuator is attracted to the fixed portion by a magnetic force to be applied.   The drive means includes a drive coil attached to the fixed portion and a drive magnet attached to the movable portion, and is further disposed on the back side of the drive coil, and the drive magnet and A coil yoke that sandwiches the first rolling member and the second rolling member by a magnetic force acting between them, the drive magnet functions as the movable part magnetic material, and the coil yoke is fixed. The actuator according to claim 7, which functions as a partial magnetic material. A lens barrel;
A plurality of imaging lenses housed in the lens barrel;
The actuator according to any one of claims 1 to 8, wherein a part of the imaging lens is attached to the movable part,
A lens unit comprising: The camera body,
The lens unit according to claim 9,
A camera characterized by comprising:

Images