JP2017003934A - Drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive unit capable of controlling movement of a movable element in each of X, Y and θ directions in a movement plane using two actuators.SOLUTION: A drive unit has a pair of actuators 4R, 4L for moving a movable element (image sensor IS with a movable support 1) in X, Y, and θ directions. The actuators 4R, 4L comprises magnets 21R, 21L that generate a magnetic field, and drive coils 11R, 11L disposed in the magnetic field to be acted on by an electromagnetic moving force when energized. The actuators 4R, 4L are positioned to face each other in a predetermined direction, and the drive coils 11R, 11L are acted on by a moving force in an oblique direction with respect to the predetermined direction when energized. The movement of the movable element is controlled using a moving force comprising a combination of moving forces generated on the drive coils 11R, 11L, which enables movement control in each of X, Y, and θ directions.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a drive device that is provided in an optical device such as a digital camera and is suitable for use in controlling movement of an optical element, and more particularly to a drive device that uses a voice coil motor (VCM) as a drive actuator.

  In an imaging device such as an optical device, especially a digital camera or a video camera, an optical element such as an image sensor or a lens is placed on a plane orthogonal to the optical axis direction when a camera shake occurs in order to prevent image quality deterioration due to camera shake imaging. In some cases, an anti-shake mechanism for moving in the X direction, Y direction, and θ direction (direction around the optical axis) is provided. In such a camera shake prevention mechanism, a voice coil motor (VCM) is often used as a driving actuator for controlling movement of an optical element. For example, Patent Documents 1 and 2 each propose a technique for controlling the movement of an optical element in a direction orthogonal to the optical axis direction by a VCM configured by a permanent magnet and a coil.

  Patent Document 1 includes two X actuators for movement control in the X direction and one or two Y actuators for movement control in the Y direction as actuators for movement control of the optical elements in the X, Y, and θ directions. It is a configuration. Similarly, Patent Document 2 is configured to include two X actuators that control movement in the X direction and two Y actuators that control movement in the Y direction. In either case, it is possible to control the movement of the optical element in the X, Y, and θ directions by controlling the movement control directions of the X and Y actuators.

JP-A-2005-352113 JP 2008-225135 A

  In Patent Documents 1 and 2, each actuator is configured to control the movement of the optical element only in either the X direction or the Y direction. As in Reference 1, at least three actuators are required. Moreover, in order to improve the ease and speed of control when moving and controlling the optical element in the θ direction, it is necessary to provide four actuators as in Patent Document 2. Thus, since Patent Documents 1 and 2 require three or four actuators, for example, when controlling the movement of the image sensor as an optical element, three or four actuators are arranged around the image sensor. This is an obstacle to downsizing the image sensor or the image pickup apparatus including the image sensor.

  An object of the present invention is to provide a drive device in which movement control in each direction of X, Y, and θ when moving a moving element is configured by two actuators.

  The drive device of the present invention includes a pair of actuators including a magnet for forming a magnetic field and a drive coil that is disposed in the magnetic field and generates a moving force due to electromagnetic force when energized. This drive device drives the moving element by the pair of actuators. The pair of actuators are arranged along a predetermined direction, and the drive coil is configured to generate a moving force in an oblique direction with respect to the predetermined direction when energized.

  As a preferred embodiment of the present invention, the drive coil includes a line portion disposed in the magnetic field region and extending obliquely with respect to a predetermined direction. In other words, the actuator includes a pair of drive coils that are integrally formed, and the wire portions of the coils are extended in diagonal directions opposite to each other. For example, each line portion of the pair of drive coils is preferably extended in an oblique direction of 45 degrees in directions opposite to each other with respect to a predetermined direction.

  In the present invention, the pair of drive coils are formed in a parallelogram shape, and the line portions serving as the oblique sides are extended in opposite oblique directions. In this case, the drive coil is arranged at a position where the line portion serving as the parallel side deviates from the magnetic field region. Moreover, a part of line part, for example, the line part used as a parallel side, is covered with a magnetic shield cover.

  The drive device of the present invention includes, for example, an optical element that is moved in a X direction, a Y direction, and a θ direction around the optical axis on a plane perpendicular to the optical axis of the optical device, and a predetermined direction across the optical axis. And a pair of actuators that move the optical element in each direction. The pair of actuators is provided with a magnet for forming a magnetic field and an electromagnetic force when placed in the magnetic field and energized. A drive coil is provided that generates a moving force. The drive coil includes a pair of coils that generate a moving force in an oblique direction opposite to a predetermined direction when energized. Each of the optical elements is moved by a combined moving force generated by at least one driving coil.

  An apparatus to which the present invention is applied is, for example, an imaging apparatus, and the moving element is configured by a movable support plate that integrally supports a drive coil, and an imaging element or an imaging lens that is supported by the movable support plate. In addition, a control circuit for controlling the current flowing through each pair of drive coils of the pair of actuators is provided, and the control circuit detects the vibration generated in the imaging device and moves the moving element so as to cancel the detected vibration. Is configured to control movement. In this case, the pair of actuators includes a Hall element that is disposed in the magnetic field region and is integrally supported by the moving element, and detects the position of the moving element based on the detection output of the Hall element. It is preferable that

  According to the present invention, since the moving element can be controlled to move in the X, Y, and θ directions by synthesizing the moving force generated in each of the two actuators, the configuration of the driving device for driving the moving element Can be simplified.

1 is a schematic perspective view showing a conceptual configuration of a camera in which the present invention is applied to a camera shake prevention device. The disassembled perspective view which looked at the camera shake prevention apparatus from the camera back side. (A) Rear view, (b) BB sectional view, (c) CC sectional view of a camera shake prevention device. The exploded view which looked at the drive coil pair from the camera back side. The circuit block diagram of the camera-shake prevention apparatus containing a control circuit. The schematic diagram and back view explaining the effect | action which carries out the movement control of the image pick-up element to a Y direction. The schematic diagram explaining the effect | action which carries out high-speed movement control of the image pick-up element in a Y direction. The schematic diagram and back view explaining the effect | action which carries out the movement control of the image pick-up element to a X direction. The schematic diagram and back view explaining the effect | action which carries out the movement control of the image pick-up element to (theta) direction. The figure similar to FIG. 3 of an actuator provided with a magnetic shield cover. The rear view of an actuator provided with a Y position sensor.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view of an embodiment in which the driving device of the present invention is applied to a camera shake prevention device SR of an image sensor IS that is built in a camera body of a camera CAM such as a still camera or a movie camera (video camera). This camera shake prevention device SR sets the image sensor IS in the X direction on a plane perpendicular to the lens optical axis Ox of the camera so as to cancel this vibration when the camera is vibrated due to camera shake or the like generated in the camera during imaging. The movement is controlled in the Y direction and further in the θ direction. Here, the X direction and the Y direction are respectively a horizontal direction and a vertical direction when the camera is held in a normal posture. Further, the θ direction is a rotation direction around the lens optical axis Ox. In this camera shake prevention device SR, the image sensor IS is arranged between the left and right as actuators for controlling the movement of the image sensor IS in the X direction, the Y direction, and the θ direction, and each is controlled by a VCM (voice coil motor). Two actuators 4R and 4L are provided. In the following, the left-right direction indicates the direction viewed from the rear of the camera CAM.

  FIG. 2 is a partially exploded perspective view of the camera shake prevention device SR as seen from the rear of the camera CM. The image pickup element IS is composed of a semiconductor image pickup element such as a CCD or a CMOS, and a movable support body with its image pickup surface facing the front of the camera CAM and the vertical direction perpendicular to the lens optical axis Ox. 1 is supported. The movable support 1 is a moving element in the present invention, and is formed in a horizontally long rectangular flat plate shape. The image pickup element IS is disposed at substantially the center of the front surface of the movable support 1, and the movable support 1 Are supported in an integrated state.

  At the front and rear positions sandwiching the movable support 1 in the direction of the lens optical axis Ox, that is, at positions facing the front and rear surfaces of the movable support 1 with a fine gap, respectively, A pair of yokes 2 and 3 made of a plate material are disposed. For the sake of convenience, the yoke 2 facing the front surface of the movable support 1 is referred to as a magnet side yoke, and the yoke 3 facing the rear surface of the movable support 1 is referred to as a coil side yoke. . The magnet side yoke 2 and the coil side yoke 3 are formed as plate members having substantially the same shape as the movable support 1, but the magnet side yoke 2 is an opening window for exposing the imaging surface of the imaging element IS. It is formed in a rectangular frame shape having 2a. The coil side yoke 3 may be simply a flat plate shape, but here, the entire portion is formed in a rectangular frame shape in order to make the portion facing the actuators 4R, 4L into a strip shape extending in the Y direction. The magnet side yoke 2 and the coil side yoke 3 are fixedly supported inside the camera CAM.

  In addition, both the yokes 2 and 3 are provided with bearing mechanisms in which rolling balls are arranged at a plurality of locations on the inner surfaces thereof, that is, the surfaces facing the movable support 1. Since this bearing mechanism is already known, the illustration thereof is omitted, but the plurality of bearing mechanisms of the magnet side yoke 2 and the coil side yoke 3 are the same number and face each other in the direction of the lens optical axis Ox. Has been placed. The rolling balls of the bearing mechanisms of the yokes 2 and 3 are brought into contact with the front and rear surfaces of the movable support 1 so as to sandwich the movable support 1 in the direction of the lens optical axis Ox. ing. As a result, the movable support 1 is sandwiched between the yokes 2 and 3 in the direction of the optical axis of the lens, and in the X direction, the Y direction, and the θ direction with respect to both the yokes 2 and 3 by rolling of the rolling balls It is possible to move.

  FIG. 3A is a rear view of the camera shake correction device SR as viewed from the rear of the camera. FIGS. 3B and 3C are taken along lines BB and CC in FIG. 3A, respectively. It is sectional drawing of the actuator 4L of the left side cut | disconnected by. Referring to FIGS. 2 and 3, two sets of driving permanent magnets that form a pair on the left and right sides of the opening window 2a are provided on the rear surface of the magnet side yoke 2, that is, the surface facing the movable support 1. A pair 21R, 21L is disposed and fixedly supported on the magnet side yoke 2. The two pairs of drive permanent magnets 21R and 21L are composed of permanent magnets MN and NS that form a pair of rectangular pieces, and the permanent magnets MN and MS are arranged at small intervals in the Y direction. It is installed.

  On the other hand, the movable support 1 is provided with two drive coil pairs 11R and 11L that are opposed to the two permanent magnet pairs 21R and 21L with the lens optical axis Ox interposed between the left and right sides. The body 1 is integrally supported. These two drive coil pairs 11R and 11L are two coils each having a small dimension (thickness dimension) in the camera front-rear direction and wound with conductive wires so as to form a substantially parallelogram when viewed from the camera front-rear direction. It is configured.

  3B and 3C show the drive coil pair 11L of the left actuator 4L, and the drive coil pair 11L includes the first coil LL1 and the second coil LL2. FIG. 4 is a diagram showing only the first coil LL1 and the second coil LL2, which are overlapped in the direction of the lens optical axis Ox in the openings 12 respectively penetrating the left and right positions of the imaging element IS of the movable support 1. In this state, the movable support 1 is disposed in a state of being embedded in the thickness direction. The right drive coil pair 11R is the same, and is composed of a first coil RL1 and a second coil RL2.

  In the coil side yoke 3, left and right frame portions 31R and 31L arranged on the left and right sides are arranged to face the drive coil pairs 11R and 11L in the direction of the lens optical axis Ox, respectively. In other words, the left and right frame portions 31R and 31L are arranged to face the permanent magnet pair 21R and 21L with the drive coil pair 11R and 11L interposed in the direction of the lens optical axis Ox.

  With the above configuration, each of the permanent magnet pairs 21R and 21L and each of the drive coil pairs 11R and 11L arranged to face the permanent magnet pairs 21R and 11L are composed of VCMs operated in cooperation with the magnet side yoke 2 and the coil side yoke 3, respectively. The actuators 4R and 4L are configured. That is, the movable support 1 is configured with the two actuators 4R and 4L described above at the left and right positions, respectively, and the movable support 1 is moved in the X, Y, and θ directions by the two actuators 4R and 4L. The movement will be controlled.

  Details of the two actuators 4R and 4L will be described. As shown in FIG. 3A, in each of the drive permanent magnet pairs 21R and 21L, the magnetic pole surfaces of the two permanent magnets MN and MS that make a pair are directed in opposite directions, and FIG. The permanent magnet MN disposed on the upper side is fixed in a state where the S pole is in contact with the magnet side yoke 2, and the N pole is directed to the rear of the camera (the front side of the paper). The permanent magnet MS disposed on the lower side of FIG. 3A is fixed in a state where the N pole is in contact with the magnet side yoke, and the S pole is directed to the rear of the camera.

  With this configuration, each drive permanent magnet pair 21R, 21L has a magnetic circuit that connects the left and right frame portions 31 of the permanent magnet MN-magnet side yoke 2-permanent magnet MS-coil side yoke 3 in a loop shape. Composed. With this magnetic circuit, in each drive permanent magnet pair 21R, 21L, the lens optical axis Ox direction of each permanent magnet pair MN, MS and the magnet side yoke 2 and the left and right frame portions 31R, 31L of the coil side yoke 3 In the minute interval, magnetic fields (magnetic fields) that are directed in the front-rear direction along the lens optical axis Ox and have different magnetic field lines (magnetic fields) are formed side by side in the Y direction. That is, in FIG. 3A, the upper permanent magnet MN forms a magnetic field of upward magnetic lines perpendicular to the paper surface, and the lower permanent magnet MS forms a magnetic field of downward magnetic force lines perpendicular to the paper surface.

  On the other hand, the first coil RL1, LL1 and the second coil RL2, ll2 constituting the drive coil pair 11R, 11L are viewed from the direction of the lens optical axis Ox, respectively, as shown in FIG. It is the structure wound so that a shape might become a parallelogram. For example, in the left drive coil pair 11L shown in FIG. 4, the first coil LL1 has side line portions sa and sb on both sides in the X direction extending along the Y direction, and the upper line portion u1 and the lower line portion d1 in the X direction. On the other hand, it is wound around a parallelogram that forms an oblique line portion that rises to the right at an angle of 45 degrees. The second coil LL2 is a parallelogram in which both side line portions sa and sb are extended along the Y direction, and the upper line portion u2 and the lower line portion d2 are left-shaded diagonal portions at an angle of 45 degrees with respect to the X direction. It is wound around.

  The first coil LL1 and the second coil LL2 are positioned on a straight line in which the left and right side line portions sa and sb extend in the Y direction, but are affected by the magnetic field formed by the permanent magnet pair 21L. It is arranged outside the magnetic field area. On the other hand, the upper line portions u1 and u2 and the lower line portions d1 and d2 of the first coil LL1 and the second coil LL2 are opposite to each other along two magnetic fields formed by the permanent magnet pair 21L, that is, the lens optical axis Ox. Arranged in the region of each magnetic field in which the magnetic field lines are directed in the direction. The upper line parts u1, u2 and the underline parts d1, d2 are arranged so as to intersect with each other in an X shape. The first coil LL1 and the second coil LL2 are integrally supported by the movable support 1 so as to overlap in the direction of the lens optical axis Ox as described above.

  The same applies to the right drive coil pair 11R shown in FIG. Here, in order to make the explanation of the operation described later easier to understand, the first coil RL1 and the second coil RL2 of the right drive coil pair 11R in FIG. 3A are referred to as a right first coil and a right second coil, respectively. The first coil LL1 and the second coil LL2 of the left drive coil pair 11L are referred to as a left first coil and a left second coil, respectively.

  The drive circuit pair 11R, 11L of the two actuators 4R, 4L, that is, the left and right first coils RL1, LL1, and the second coils RL2, LL2, as shown in FIG. . The control circuit 100 is a camera shake prevention control circuit, and an X gyro Gx for detecting an X-axis (camera horizontal axis) angular velocity, a Y-axis (camera vertical axis) angular velocity, and a Z-axis (camera optical axis) angular velocity generated in the camera. , Y gyro Gy and Z gyro Gz are connected. Since these gyros Gx, Gy, and Gz are already known, a detailed description thereof is omitted here.

  Further, it differs in the X direction from the X position sensor Sx that detects the moving position of the movable support 1 in the X direction in order to feedback control the energization to the first coils RL1, LL1 and the second coils RL2, LL2. A Y1 position sensor Sy1 and a Y2 position sensor Sy2 are connected to detect the movement positions in the Y direction at the two positions. Further, the position sensors Sx, Sy1, and Sy2 are sensors using Hall elements, and the principle of position detection by these sensors is already known, so that the detailed description thereof is omitted.

  The control circuit 100 detects a change in the posture of the camera CAM in the XYZ directions from the angular velocities detected by the gyros Gx, Gy, and Gz, and the movable support detected by the position sensors Sx, Sy1, and Sy2 so as to cancel the change. The magnitude and direction of current supplied to the body 1, that is, the right first coil RL1, the right second coil RL2, the left first coil LL1, and the left second coil LL2 with reference to the moving position of the image sensor IS. Control. As a result, the XYθ position of the movable support 1, that is, the imaging element IS is set to a predetermined position by electromagnetic force generated by the coils RL1, RL2, LL1, LL2 and the magnetic field formed by the drive permanent magnet pairs 21R, 21L. Control and prevent camera shake.

  The movement control for preventing the shaking of the movable support 1 by the two actuators 4R and 4L having the above configuration will be described. When camera shake occurs during imaging with the camera CAM, the X, Y, and Z gyros Gx, Gy, and Gz detect vibrations caused by camera shake, that is, X, Y, and Z axial angular velocities, and input them to the control circuit 100. At the same time, the position sensors Sx, Sy1, and Sy2 for X, Y1, and Y2 detect the positions of the movable support 1 for X, Y1, and Y2, and input them to the control circuit 100. The control circuit 100 calculates the XYθ position variation of the camera CAM from the input angular velocity, and controls the movement of the movable support 1 so that the input X, Y1, Y2 positions are positions that cancel the XYθ position variation. That is, control currents that flow through the left and right first coils RL1, LL1 and second coils RL2, LL2 are generated, and the generated control currents are passed through these coils.

  In each of the coils RL1, RL2, LL1, and LL2, a moving force (Lorentz force: electromagnetic force according to Fleming's left-hand rule) is generated between the coils RL1, RL2, LL1, and LL2. The moving force generated in each of the coils RL1, RL2, LL1, LL2 becomes a driving force for moving the movable support 1, and the movable support 1 is moved in the XYθ direction by a combined moving force obtained by combining these moving forces. . As a result, the movable support 1 and the image sensor IS can be controlled to move to positions where XYθ position fluctuations due to camera shake occurring in the camera CAM are offset, thereby preventing camera shake.

  6A and 6B are diagrams for explaining the operation of the two actuators 4R and 4L when the movable support 1 is moved in the Y direction. FIG. 6A is a schematic view, and FIG. 6B is a rear view corresponding to FIG. FIG. Here, a state is shown in which the movable support 1 is moved in the positive Y direction (upward in FIG. 6). A current in the ccw (counterclockwise) direction is passed through the left second coil LL2, and the right first coil RL1. Current in the ccw direction. No current flows through the left first coil LL1 and the right second coil RL2. The left second coil LL2 moves upward and diagonally to the right in FIG. 6 due to the Lorentz force generated between the magnetic field generated by the permanent magnet pair 21L and the upper line portion u2 and the lower line portion d2 disposed in the magnetic field region. A force F1 is generated. On the other hand, in the right first coil RL1, the Lorentz force generated between the magnetic field generated by the permanent magnet pair 21R and the upper line portion u1 and the lower line portion d1 disposed in the magnetic field region is directed obliquely upward to the left in FIG. A moving force F2 is generated.

  Thereby, the moving force F1 generated in the left second coil LL2 and the moving force F2 generated in the right first coil RL1 are combined to form a combined moving force in the Y upward direction, that is, the Y positive direction, as shown in FIG. As shown in b), the movable support 1 is moved in the Y positive direction. At this time, in the X direction, the moving forces F1 and F2 of the left second coil LL2 and the right first coil RL1 cancel each other, so that the movable support 1 is not moved in the X direction. Since the left and right side line portions sa and sb of the left and right first coils and the second coil are not arranged in the magnetic field region, no moving force is generated in the left and right side line portions sa and sb.

  At this time, as shown in FIG. 7, a current in the ccw direction is further passed through the left first coil LL1 to generate a moving force F3 obliquely upward to the left, and a current in the ccw direction is applied to the right second coil RL2. It is also possible to generate a moving force F4 that flows through and flows obliquely upward to the right, and to generate a combined moving force in the positive Y direction by combining these moving forces F1 to F4. Therefore, by synthesizing all the moving forces F1 to F4 generated in the four coils RL1, RL2, LL1, and LL2, a larger combined moving force is generated, and the movable support 1 is controlled to move in the Y direction at high speed. Is possible. For example, the present invention can be applied to the case where it is desired to generate the maximum moving force in the two actuators 4R and 4L when the release button of the camera is half pressed.

  When the movable support is moved in the negative Y direction (downward in the figure), it is only necessary to pass a current in the opposite direction to that when the movable support is moved in the positive Y direction with respect to the coils RL1, LL1, RL2, and LL2. . That is, a current in the cw (clockwise) direction is passed through the left second coil LL2, and a current in the cw direction is passed through the right first coil RL1. Alternatively, or simultaneously, a current in the cw direction may be passed through the left first coil LL1, and a current in the cw direction may be passed through the right second coil RL2.

  When moving in the Y positive direction or the Y negative direction, instead of the current control described above, no current is passed through the left second coil LL2 and the right first coil RL1, but the left first coil LL1 and the right coil A current may be passed through the second coil RL2, and the movable support 1 may be moved only by the moving force generated in the second coil RL2.

  FIG. 8A is a schematic diagram for explaining the action of the two actuators 4R and 4L when the movable support 1 is moved in the X direction, and FIG. 8B is a diagram similar to FIG. 6A. is there. Here, a state is shown in which the movable support 1 is moved in the positive X direction (right direction in the figure). A current in the cw direction is applied to the left first coil LL1, and a current in the ccw direction is applied to the left second coil LL2. Circulate. A current in the cw direction is passed through the right first coil RL1, and a current in the ccw direction is passed through the right second coil RL2. In the left first coil LL1 and the left second coil LL2, due to the Lorentz force generated between the magnetic field by the permanent magnet pair 21L and the upper line parts u1, u2 and the lower line parts d1, d2 arranged in this magnetic field region, A moving force F5 directed diagonally downward to the right and a moving force F6 directed diagonally upward to the right are generated in FIG. On the other hand, in the right first coil RL1 and the right second coil RL2, the Lorentz force generated between the magnetic field generated by the permanent magnet pair 21R and the upper line parts u1, u2 and the lower line parts d1, d2 arranged in this magnetic field region. As a result, a moving force F5 directed diagonally downward to the right and a moving force F6 directed diagonally upward to the right are generated.

  Thereby, the moving force F5 and the moving force F6 generated in the left and right coils LL1, LL2, RL1, and RL2 are combined to form a combined moving force in the X right direction, that is, the X positive direction. The element IS is moved in the X positive direction. In the Y direction, the movable supports 1 are not moved in the Y direction because the moving forces F5 and F6 of the coils LL1, LL2, RL1, and RL2 are canceled out. At this time, since the left and right side line portions sa and sb of the left and right first coils LL1 and RL1 and the second coils LL2 and RL2 are not arranged in the magnetic field region, a moving force is generated in the left and right side line portions sa and sb. Never do.

  When the movable support 1 is moved in the X negative direction (left direction in the figure), a current may be passed through each coil RL1, LL1, RL2, LL2 in the direction opposite to the X positive direction. That is, a current in the ccw direction is passed through the left first coil LL1, a current in the cw direction is passed through the left second coil LL2, a current in the ccw direction is passed through the right first coil RL1, and a current in the right second coil RL2 is passed. What is necessary is just to pass the electric current of a cw direction.

  FIG. 9A is a schematic diagram for explaining the action of the two actuators 4R and 4L when the movable support 1 is moved in the θ direction, and FIG. 8B is a diagram similar to FIG. 6A. is there. Here, a state is shown in which the movable support 1 is moved in the positive direction of θccw (counterclockwise direction in the figure), current in the cw direction is passed through the left first coil LL1, and ccw is passed through the right first coil RL1. Pass current in the direction. No current flows through the left second coil LL2 and the right second coil RL2. In the left first coil LL1, a moving force directed diagonally downward to the right in the figure by the Lorentz force generated between the magnetic field generated by the permanent magnet pair 21L and the upper line portion u1 and the lower line portion d1 disposed in the magnetic field region. F7 occurs. On the other hand, in the first right coil RL1, the Lorentz force generated between the magnetic field generated by the permanent magnet pair 21R and the upper line portion u1 and the lower line portion d1 disposed in the magnetic field region is directed diagonally upward to the left in the figure. A moving force F8 is generated.

  Accordingly, the moving force F7 generated in the left first coil LL1 and the moving force F8 generated in the right first coil RL1 act in the same circumferential tangent direction with respect to the lens optical axis Ox. As a result, the moving force F7 , F8 forms a combined moving force in the θccw direction, that is, in the counterclockwise direction, and the movable support 1 and the imaging element IS are moved in the counterclockwise direction. At this time, since the moving forces F7 and F8 of the coils LL1 and RL1 are canceled in the X direction and the Y direction, the movable support 1 is not moved in the X and Y directions. Since the left and right side line portions sa and sb of the left first coil LL1 and the right first coil RL1 are not arranged in the magnetic field region, no moving force is generated in the left and right side line portions sa and sb.

  In addition, the cw direction current is passed through the left second coil LL2 to generate a leftward downward moving force, and the ccw direction current is passed through the right second coil RL2 and the rightward upward movement is performed. Forces may be generated, and these moving forces may be combined to generate a combined moving force in the θccw direction.

  When the movable support 1 is moved in the θcw direction (clockwise direction in the figure), a current may be passed through the coils RL1, LL1, RL2, and LL2 in the direction opposite to that in the θccw direction. That is, a current in the ccw direction is passed through the left first coil LL1, and a current in the cw direction is passed through the right first coil RL1. Alternatively, a current in the ccw direction may be passed through the left second coil LL2, and a current in the cw direction may be passed through the right second coil RL2.

  In the above embodiment, the left and right side line portions sa and sb of the four coils RL1, LL1, RL2 and LL2 are not arranged in the magnetic field region formed by the permanent magnet pair 21R and 21L. , Sb so as not to generate a Lawrence force. Therefore, each coil RL1, LL1, RL2, LL2, more specifically, the left-right dimension of the left and right coil pairs 11R, 11L, that is, the X-direction dimension is larger than the X-direction dimension of the permanent magnet pair 21R, 21L. This is an obstacle to downsizing the actuators 4R and 4L.

  Therefore, in the modification of this embodiment, as shown in FIG. 10, magnetic shield covers 5 are provided on the left and right side line portions sa and sb of each coil so as not to be affected by the magnetic field. FIGS. 10A, 10B and 10C are views similar to FIG. 3, and a magnetic shield cover 5 is formed by processing a metal plate into a cylindrical shape having a U-shaped cross section. 5 is placed on the left and right side lines sa and sb of the coils RL1, LL1, RL2 and LL2.

  Thereby, even if the left and right side line portions sa and sb are arranged in the magnetic field region of the permanent magnet pair 21R and 21L, they are not affected by the magnetic field due to the magnetic shielding effect of the magnetic shield cover 5, and each coil RL1, LL1, RL2, Even when a current is passed through LL2, no Lorentz force is generated in the left and right side line portions sa and sb, and the upper line portions u1 and u2 and the lower line portions d1 and d2 of the coils RL1, LL1, RL2, and LL2 respectively. Appropriate movement control in the XYθ directions of the movable support 1 and the image sensor IS can be realized without affecting the movement force due to the generated Lorentz force. In addition, this makes it possible to make the dimension of each coil pair 11R, 11L in the X direction smaller than the dimension of the permanent magnet pair 21R, 21L in the X direction, thereby reducing the size of the coil pair 11R, 11L or the actuators 4R, 4L. Can be miniaturized.

  As a modification of the embodiment, as shown in FIG. 11, the Y actuators 4R and 4L are each provided with a Y position sensor, that is, the right actuator 4R is provided with a Y1 position sensor Sy1, and the left actuator 4L is provided with a Y2 position sensor Sy2. May be provided. That is, Hall elements as position sensors Sy1 and Sy2 are arranged at intermediate positions in the Y direction between the permanent magnets MN and MS of the permanent magnet pairs 21R and 21L of the actuators 4R and 4L. To support. The Y1 position sensor Sy1 and the Y2 position sensor Sy2 made up of the Hall elements detect their position relative to the permanent magnet pair 21R, 21L by detecting a change in magnetic flux of the magnetic field formed by the permanent magnet pair 21R, 21L and changing the output current. That is, it is possible to detect the position of the movable support 1 along the Y direction which is the arrangement direction of the permanent magnets MN and MS arranged in the Y direction constituting the permanent magnet pair 21R and 21L. Yes.

  Therefore, when the movable support 1 moves in the Y direction, the Y1 position in the Y direction is detected by the Y1 position sensor Sy1 provided in the right actuator 4R, and the Y2 position sensor Sy2 provided in the left actuator 4L. The Y2 position is detected. Accordingly, if the change in the Y1 position and the Y2 position is detected, it can be detected that the movable support 1 has moved in the Y direction. At that time, if the Y1 position and the Y2 position are compared, the inclination in the Y direction, that is, the θ direction is detected. Can also be detected. For example, when Y1 = Y2, it can be detected that the movable support 1 has moved in the Y direction while maintaining a horizontal state. When Y1 ≠ Y2, it can be detected that the movable support 1 is tilted, that is, moved in the θ direction.

  As described above, the Y1 position sensor Sy1 and the Y2 position sensor Sy2 are integrally provided in the two actuators 4R and 4L, respectively, so that the permanent magnets required for the position sensor using the Hall elements are the permanent magnets of the actuators 4R and 4L. The pair 21R and 21L can be shared, and the configuration of the camera shake prevention device SR can be simplified as compared with the case where the Y1 position sensor Sy1 and the Y2 position sensor Sy2 are provided independently.

  In the embodiment, the shape of the first and second coils constituting each actuator is formed in a parallelogram, but the first coil line portion and the second coil line portion that generate Lorentz force are What is necessary is just to be extended in the direction orthogonal to each other. Therefore, one leg may be formed in a trapezoidal shape that is orthogonal to each other, and further, one leg may be formed in a triangle that is orthogonal to each other, or another polygon. In any case, it is preferable that the line portions other than the line portions that generate the Lorentz force are arranged at positions where they are removed from the magnetic field region, or are covered with a magnetic shield cover.

  In the embodiment, two actuators are arranged along the X direction. However, the actuators only need to be arranged at symmetrical positions with the optical axis in between. Therefore, it is good also as a structure which has arrange | positioned two actuators along a Y direction. In this case, in order to reduce the arrangement space in the Y direction, the permanent magnet pair of each actuator may be configured such that a pair of permanent magnets is arranged along the X direction.

  In the above embodiments, the drive device of the present invention is applied to a camera shake prevention device. However, it is also possible to apply the drive device as a drive device for driving other optical elements that are provided in an optical apparatus and controlled in movement. . For example, it can be configured as a camera shake prevention device drive device that is arranged in the lens barrel of a camera and moves a part of the lenses constituting the lens optical system in the XYθ direction on a plane orthogonal to the lens optical axis. It is. Further, it goes without saying that the present invention can be applied as a drive device that controls movement of the moving element in the XYθ direction in devices other than optical devices.

1 Movable support (moving element)
2 Magnet side yoke 3 Coil side yoke 4R, 4L Actuator (VCM: Voice coil motor)
5 Magnetic shield cover 100 Control circuit 11R, 11L Drive coil pair 21R, 21L Permanent magnet pair RL1, LL1 First coil RL2, RL2 Second coil SR Camera shake prevention device IS Image sensor CAM Camera MN, MS Permanent magnet Gx, Gy, Gz Gyro sensor Sx, Sy1, Sy2 Position sensor

Claims (14)

  A magnet for forming a magnetic field and a pair of actuators provided in the magnetic field and provided with a drive coil that generates a moving force due to electromagnetic force when energized are driven by the actuator. In the driving device, the pair of actuators are arranged along a predetermined direction, and the driving coil is configured to generate a moving force in an oblique direction with respect to the predetermined direction when energized. The drive device characterized.   The drive device according to claim 1, wherein the drive coil includes a line portion disposed in the magnetic field region and extending obliquely with respect to a predetermined direction.   The drive device according to claim 2, wherein each of the actuators includes a pair of drive coils integrally formed, and the wire portions of the coils are extended in diagonal directions opposite to each other.   4. The driving device according to claim 3, wherein each line portion of the pair of driving coils is extended in an oblique direction of 45 degrees in directions opposite to each other with respect to the predetermined direction.   5. The drive device according to claim 4, wherein the pair of drive coils are formed in a parallelogram shape, and the line portions that form the oblique sides are extended in opposite oblique directions.   The drive device according to claim 5, wherein the drive coil is disposed at a position where a line portion serving as a parallel side deviates from the magnetic field region.   The drive device according to claim 1, wherein a part of the drive coil is covered with a magnetic shield cover.   The drive device according to claim 6, wherein the drive coil is covered with a magnetic shield cover at a line portion serving as the parallel side.   9. The moving force generated in each drive coil is controlled by controlling the direction of a current flowing through a selected drive coil or all of the drive coils among each pair of drive coils of the pair of actuators. The drive apparatus in any one.   Each driving coil of the pair of actuators is integrally supported by the moving element, and the moving element is combined with the moving force generated by each driving coil in the moving plane in the X direction, the Y direction, and the light. The drive device according to claim 9, wherein the drive device is moved in a θ direction around an axis.   An optical element that is moved in a X direction, a Y direction, and a θ direction around the optical axis on a plane perpendicular to the optical axis of the optical device, and is disposed along a predetermined direction across the optical axis, A drive device for an optical apparatus comprising a pair of actuators that move in the respective directions, wherein the pair of actuators are disposed in the magnetic field and electromagnetic when energized. A driving coil that generates a moving force due to a force, and the driving coil is composed of a pair of coils that generate a moving force in an oblique direction opposite to the predetermined direction when energized; A driving apparatus that moves the optical element with a combined moving force generated by at least one driving coil of each of the pair of actuators.   The optical device is an imaging device, and the optical element includes a movable support plate that integrally supports the drive coil, and an imaging element or an imaging lens that is supported by the movable support plate. Drive device.   A control circuit for controlling a current flowing through each pair of drive coils of the pair of actuators, wherein the control circuit detects vibration generated in the imaging device and cancels the detected vibration; The drive device according to claim 12, wherein the movement of the drive is controlled. The pair of actuators includes a Hall element disposed in the magnetic field region and integrally supported by the optical element, and detects a position of the optical element based on a detection output of the Hall element. Thru | or 12. The drive device in any one of 12.

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