JP4981484B2 - Drive device - Google Patents

Description

  The present invention relates to a driving device that drives a moving body using elliptical vibration of a vibrator and moves the moving body in a predetermined direction, and an imaging device such as a digital camera that performs shake correction by the driving device.

  In an imaging apparatus such as a camera, a camera shake correction apparatus for preventing image degradation due to camera shake is generally provided. As a blur correction function provided in such an imaging apparatus such as a camera, a shake vibration in the camera pitch direction and a shake vibration in the camera yaw direction are detected using a shake detection unit such as an angular velocity sensor, and based on the detected shake signal. Thus, a part of the image pickup optical system or the image pickup element is independently shifted in the horizontal direction and the vertical direction in a plane orthogonal to the photographing optical axis in the direction to cancel the blur, so that the image on the image pickup surface of the image pickup element is A camera shake correction function for correcting camera shake is known.

  In a camera shake correction mechanism that realizes such a camera shake correction function, in order to correct camera shake, a part of the photographing lens or the image sensor itself is horizontally and vertically within a plane perpendicular to the photographing optical axis. Driving means moving in the direction are used. This drive means is required to have high responsiveness, precision drive (micro drive), and self-holding ability to hold the position of the moving body even when the power is turned off in order to operate following camera shake. In response to such demands, the vibration wave actuator is suitable because of its high responsiveness and self-holding characteristics.

  In an actuator using vibration such as a so-called ultrasonic motor, a pressing mechanism is required to press the vibrator and the moving body. For example, in Patent Document 1, the side opposite to the side where the vibrator is in contact with the moving body. Are pressed using a coil spring. Similarly, in Patent Document 2, the vibrator is pressed using a leaf spring from the side opposite to the side in contact with the moving body.

JP 2006-094591 A JP 2006-158053 A

  However, in the technique described in Patent Document 1 in which the moving body, the vibrator, and the coil spring are stacked, the technique described in Patent Document 1 that presses with the coil spring disposed on the side opposite to the side on which the vibrator and the moving body contact each other increases the size. On the other hand, in the technique described in Patent Document 2 using a leaf spring, although it is possible to reduce the size, it is difficult to obtain a stable pressing force because the leaf spring is used. In these techniques, the vibrator is pressed near the vibration node so that the vibrator can be stably pressed even if the vibrator vibrates. However, when the vibrator vibrates at a high frequency, the vibration cannot be completely prevented from being transmitted to the pressing member that presses the vibrator, and the entire system vibrates due to the vibration transmitted to the pressing member. It becomes. Further, there may be a problem that an audible sound is generated due to the vibration of the pressing member.

  The present invention has been made in view of the above, and has a structure that can be miniaturized, can press an oscillator that generates elliptical vibrations in a stable pressing state against a moving body, and It is an object of the present invention to provide a driving device and an imaging device that can suppress the influence of vibration.

  In order to solve the above-described problems and achieve the object, a drive device according to the present invention holds a vibrator that generates elliptical vibration in a drive unit when a predetermined frequency voltage signal is applied, and the vibrator. A fixing member, a moving body that is moved by elliptical vibration generated in the drive unit when the drive unit of the vibrator is pressed, and a position corresponding to a vibration node of the vibrator, the vibrator and the vibrator A pressing member that contacts the vibrator on a side opposite to the side on which the moving body comes into contact; a pressing member that presses the vibrator toward the moving body; and the pressing member that faces the vibrator Pressurizing means for energizing, and the pressurizing means is disposed between a portion where the movable body and the vibrator come into contact with each other and a portion where the pressing member and the vibrator come into contact with each other, The pressing member is attached to the fixed member via a vibration damping member. And wherein the Rukoto.

  The drive device according to the present invention is characterized in that, in the above invention, the pressing member is held movably in the pressing direction while being positioned with respect to the fixed member via the vibration damping member.

  In the driving device according to the present invention, in the above invention, the pressing member is formed in a shape having a longitudinal direction, and the pressurizing means is an end portion of the pressing member in the longitudinal direction at a side of the vibrator. It is arranged in.

  Moreover, the drive device according to the present invention is characterized in that, in the above invention, the pressing member is attached with a second vibration damping member.

  In the drive device according to the present invention as set forth in the invention described above, the second vibration damping member is adhered to the pressing portion with which the convex portion of the vibrator contacts.

  In addition, an imaging apparatus according to the present invention includes a camera shake correction apparatus that displaces the imaging element in a first direction orthogonal to the imaging optical axis and a second direction orthogonal to the imaging optical axis and the first direction. In the imaging apparatus, a first vibrator in which elliptical vibration is generated in the drive unit when a predetermined frequency voltage is applied, a fixing member having a first holding unit that holds the first vibrator, and the first A first moving body that is pressed in a direction parallel to the photographing optical axis and moved in the first direction with respect to the fixed member by elliptic vibration generated in the driving unit; A second vibrator that is held by a second holding unit provided in the first moving body and generates elliptical vibration in the driving unit when a predetermined frequency voltage is applied; and the second vibrator The drive unit is pressed from a direction parallel to the photographic optical axis, and is generated in the drive unit. The second moving body that holds the image sensor and the vibration node of the first vibrator are moved in the second direction with respect to the first moving body by elliptic vibration. A pressing portion that comes into contact with the first vibrator on a side opposite to the side on which the first vibrator and the first moving body come into contact, and the first vibrator A first pressing member that presses the first moving body toward the first moving body, a portion where the first moving body and the first vibrator contact with each other in the photographing optical axis direction, and the first pressing member. A first pressurizing means disposed between the first vibrator and the first vibrator for biasing the first pressing member toward the first vibrator; and the second vibration. A position corresponding to a node of vibration of the child, and the second vibrator and the second vibrator on the side opposite to the side where the second vibrator and the second moving body abut. A second pressing member that presses the second vibrator toward the second moving body, and the second moving body and the second vibrator in the photographing optical axis direction. And the second pressing member are arranged between the portion that contacts the second vibrator and biases the second pressing member toward the second vibrator. Second pressing means, and the first pressing member is attached to the fixing member so as to be movable in a pressing direction via a vibration damping member, and the second pressing member is It is attached to the first moving body so as to be movable in the pressing direction via a vibration damping member.

  According to the driving device and the imaging apparatus according to the present invention, the pressing unit is arranged between the portion where the moving body and the vibrator contact and the portion where the pressing member and the vibrator contact, and the pressing member is placed in the vibrator. Since the pressure is applied toward the moving body, the vibrator that generates elliptical vibration can be pressed in a stable pressing state with a structure that can be downsized without increasing in size in the pressing direction. Is attached to the fixed member via the vibration damping member, so that even if the vibration of the vibrator is transmitted to the pressing member, the vibration transmission to the system subsequent to the fixed member to which the pressing member is attached can be suppressed. There is an effect that can be done.

  The best mode for carrying out a drive device and an imaging device according to the present invention will be described below with reference to the drawings. The imaging apparatus according to the present embodiment is equipped with a driving device for performing camera shake correction of an imaging unit including an imaging element that obtains an image signal by photoelectric conversion. An application example to a flex-type electronic camera (digital camera) will be described.

  First, a system configuration example of the camera according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram schematically showing mainly an electrical system configuration of the camera of the present embodiment. The camera according to the present embodiment is configured by a system including a body unit 100 as a camera body and a lens unit 10 as an interchangeable lens that is one of accessory devices.

  The lens unit 10 is detachable through a lens mount (not shown) provided on the front surface of the body unit 100. The lens unit 10 is controlled by its own lens control microcomputer (hereinafter referred to as “Lucom”) 5. The body unit 100 is controlled by a body control microcomputer (hereinafter referred to as “Bucom”) 50. These Lucom 5 and Bucom 50 are electrically connected via the communication connector 6 in a state where the lens unit 10 is mounted on the body unit 100. As a camera system, the Lucom 5 is configured to operate in cooperation with the Bucom 50 in a dependent manner.

  The lens unit 10 includes a photographing lens 1 and a diaphragm 3. The taking lens 1 is driven by a DC motor (not shown) provided in the lens driving mechanism 2. The diaphragm 3 is driven by a stepping motor (not shown) provided in the diaphragm driving mechanism 4. Lucom 5 controls each of these motors based on a command from Bucom 50.

  In the body unit 100, the following components are arranged as shown in the figure. For example, a single-lens reflex component (penta prism 12, quick return mirror 11, eyepiece lens 13, submirror 11a) as an optical system, a focal plane shutter 15 on the photographing optical axis, and a reflected light beam from the submirror 11a In response, an AF sensor unit 16 for detecting the defocus amount is provided.

  Also, an AF sensor driving circuit 17 for driving and controlling the AF sensor unit 16, a mirror driving circuit 18 for driving and controlling the quick return mirror 11, and a shutter charging mechanism 19 for charging a spring for driving the front curtain and the rear curtain of the shutter 15. A shutter control circuit 20 that controls the movement of the front and rear curtains, and a photometric circuit 21 that performs photometric processing based on a photometric sensor 21a that detects the light flux from the pentaprism 12 are provided.

  An imaging unit 30 for photoelectrically converting a subject image that has passed through the optical system is provided on the photographing optical axis. The image pickup unit 30 is formed by integrating a CCD 31 that is an image pickup element, an optical low-pass filter (LPF) 32 and a dustproof filter 33 disposed on the front surface thereof as a unit. A piezoelectric element 34 is attached to the periphery of the dust filter 33. The piezoelectric element 34 has two electrodes, and the dust-proof filter 33 is vibrated by vibrating the piezoelectric element 34 at a predetermined frequency by the dust-proof filter control circuit 48 to remove dust attached to the filter surface. Configured to get. An anti-vibration unit for camera shake correction, which will be described later, is added to the imaging unit 30.

  The camera system of the present embodiment also includes a CCD interface circuit 23 connected to the CCD 31, a liquid crystal monitor 24, an SDRAM 25 that functions as a storage area, a flash ROM 26, and an image processing controller 28 that performs image processing. The electronic recording display function can be provided together with the electronic imaging function. Here, the recording medium 27 is an external recording medium such as various memory cards or an external HDD, and is mounted so as to be communicable with the camera body via a communication connector and exchangeable. Then, image data obtained by photographing is recorded on the recording medium 27. As the other storage area, a non-volatile memory 29 made of, for example, an EEPROM for storing predetermined control parameters necessary for camera control is provided so as to be accessible from the Bucom 50.

  The Bucom 50 is provided with an operation display LCD 51 and an operation display LED 51a for notifying the user of the operation state of the camera by display output, and a camera operation SW52. The camera operation SW 52 is a switch group including operation buttons necessary for operating the camera, such as a release SW, a mode change SW, and a power SW. Furthermore, a battery 54 as a power source and a power circuit 53 that converts and supplies the voltage of the battery 54 to a voltage required by each circuit unit constituting the camera system are provided, and current is supplied from an external power source via a jack. A voltage detection circuit for detecting a voltage change when supplied is also provided.

  Each part of the camera system configured as described above generally operates as follows. First, the image processing controller 28 takes in image data from the CCD 31 by controlling the CCD interface circuit 23 in accordance with an instruction from the Bucom 50. This image data is converted into a video signal by the image processing controller 28 and output and displayed on the liquid crystal monitor 24. The user can confirm the captured image from the display image on the liquid crystal monitor 24.

  The SDRAM 25 is a memory for temporarily storing image data, and is used as a work area when image data is converted. The image data is stored in the recording medium 27 after being converted into JPEG data.

  The mirror drive mechanism 18 is a mechanism for driving the quick return mirror 11 to the up position and the down position. When the quick return mirror 11 is in the down position, the light flux from the photographing lens 1 is on the AF sensor unit 16 side. The light is divided and guided to the pentaprism 12 side. The output from the AF sensor in the AF sensor unit 16 is transmitted to the Bucom 50 via the AF sensor driving circuit 17 and a known distance measurement process is performed. On the other hand, a part of the light beam that has passed through the pentaprism 12 is guided to a photometric sensor 21a in the photometric circuit 21, and a known photometric process is performed based on the amount of light detected here.

  Next, the imaging unit 30 including the CCD 31 will be described with reference to FIG. FIG. 2 is a longitudinal side view illustrating a configuration example of the imaging unit 30. The imaging unit 30 is disposed on the side of the photoelectric conversion surface of the CCD 31 and a CCD 31 as an imaging device that obtains an image signal corresponding to the light that is transmitted through the imaging optical system and irradiated on its own photoelectric conversion surface. An optical low-pass filter (LPF) 32 that removes a high-frequency component from a subject light beam that is transmitted through the filter, a dust-proof filter 33 that is opposed to the optical LPF 32 at a predetermined interval on the front side, and a periphery of the dust-proof filter 33 And a piezoelectric element 34 which is disposed in the part and applies predetermined vibration to the dustproof filter 33.

  Here, the CCD chip 31a of the CCD 31 is directly mounted on the flexible substrate 31b disposed on the fixed plate 35, and connectors 31c and 31d extending from both ends of the flexible substrate 31b are provided on the main circuit board 36. It is connected to the main circuit board 36 side through 36a and 36b. The protective glass 31e of the CCD 31 is fixed on the flexible substrate 31b via a spacer 31f.

  A filter receiving member 37 made of an elastic member or the like is disposed between the CCD 31 and the optical LPF 32. The filter receiving member 37 is disposed at a position that avoids the effective range of the photoelectric conversion surface at the peripheral edge of the front surface of the CCD 31, and is in contact with the vicinity of the peripheral edge of the optical LPF 32 so that the CCD 31 and the optical LPF 32 It is comprised so that substantially airtightness may be maintained between. A holder 38 that covers the CCD 31 and the optical LPF 32 in an airtight manner is disposed. The holder 38 has a rectangular opening 38a at a substantially central portion around the photographing optical axis, and a step portion 38b having a substantially L-shaped cross section is formed on the inner peripheral edge of the opening 38a on the dustproof filter 33 side. The optical LPF 32 and the CCD 31 are disposed from the rear side of the opening 38a. Here, the optical LPF 32 is positioned so that the front side peripheral edge of the optical LPF 32 is in substantially airtight contact with the stepped portion 38b, whereby the position of the optical LPF 32 in the photographing optical axis direction is regulated by the stepped portion 38b. The front side is secured from the inside.

  On the other hand, a dust-proof filter receiving portion that protrudes to the front side of the step portion 38b around the step portion 38b in order to hold the dust-proof filter 33 on the front surface of the optical LPF 32 at a predetermined interval at the peripheral portion on the front side of the holder 38. 38c is formed over the entire circumference. The dustproof filter 33 formed in a circular or polygonal plate shape as a whole is formed of an elastic body such as a leaf spring and is pressed by a pressing member 40 fixed to the dustproof filter receiving portion 38c with a screw 39. It is supported by the part 38c. Here, an annular seal 41 is interposed between the piezoelectric element 34 portion disposed on the outer peripheral edge portion on the back side of the dustproof filter 33 and the dustproof filter receiving portion 38c, thereby ensuring an airtight state. The imaging unit 30 is configured in an airtight structure including the holder 38 formed in a desired size for mounting the CCD 31 in this way.

  Next, the camera shake correction function of the camera according to the present embodiment will be described. In the present embodiment, when the direction of the photographing optical axis is the Z-axis direction, the X-axis direction that is the first direction orthogonal to the XY plane orthogonal to the photographing optical axis and the Y-axis direction that is the second direction. The image pickup device CCD 31 is displaced and moved so as to compensate for blurring. The image stabilization unit including a camera shake correction drive device is subjected to elliptical vibration in the drive unit when a predetermined frequency voltage is applied. The holder 38 on which the CCD 31 in the imaging unit 30 is mounted is configured as a moving object.

  First, an operation principle of a vibrator used as a drive source in the drive device of the present embodiment will be described. FIG. 3 is a schematic diagram showing the operation principle of the vibrator. The vibrator 200 includes a piezoelectric body 201 formed in a rectangular shape with a predetermined size, a pair of drive electrodes 202 and 203 formed so as to be symmetrical with respect to one side of the piezoelectric body 201, and the drive electrode 202. , 203 and drive elements 204, 205 as drive units provided at the surface position of the piezoelectric body 201. When a + voltage is applied to the drive electrode 202, as shown in FIG. 3A, the drive electrode 202 portion is deformed to be extended, while the back surface side piezoelectric body 201 portion is not deformed to be extended. Deforms into an arc. Conversely, when a negative voltage is applied to the drive electrode 202, as shown in FIG. 3C, the drive electrode 202 part is deformed so as to shrink, while the back side piezoelectric body 201 part is not shrunk. It is deformed into an arcuate shape opposite to that in FIG. The same applies to the drive electrode 203 side.

  Therefore, in order to generate elliptical vibrations on the surfaces of the driver elements 204 and 205, a frequency voltage based on a sine wave having a predetermined frequency is applied to one of the polarized drive electrodes 202 of the piezoelectric body 201 and to the other drive electrode 203. A frequency voltage by a sine wave having a phase shift at the same frequency as the frequency voltage applied to the drive electrode 202 is applied. The frequency of the applied frequency voltage is such that the center of the piezoelectric body 201 is a bending vibration node, the driver elements 204 and 205 are antinodes of bending vibration, and the longitudinal vibration node of the piezoelectric body 201 coincides with the bending vibration node. It is set to a predetermined numerical value. Then, the vibrator 200 repeats the bending vibration shown in FIGS. 3A to 3C including the restored state shown in FIG. Elliptical vibrations are generated on the surfaces of the children 204 and 205. Therefore, by placing the movable body to be driven on the driver elements 204 and 205 side of the vibrator 200 while being in pressure contact with each other, the movable body moves according to the direction of the elliptical vibration generated on the surfaces of the driver elements 204 and 205. It becomes.

  At this time, by changing the phase difference of the frequency voltage applied to the drive electrodes 202 and 203, it is possible to change the shape of the elliptical vibration generated on the surfaces of the drive elements 204 and 205, thereby driving the vibrator 200. Thus, the moving speed of the moving moving body can be changed. For example, if the phase difference of the frequency voltage is 0 °, the speed is 0. However, if the phase difference is increased, the speed gradually increases, the maximum speed is reached when the phase difference is 90 °, and the phase difference is increased beyond 90 °. Then, on the contrary, the speed gradually decreases, and when the phase difference is 180 °, the speed becomes zero again. When the phase difference is set to a negative value, the rotational direction of the elliptical vibration generated in the driver elements 204 and 205 is reversed, and the moving body can be driven in the reverse direction. Also in this case, the maximum speed is obtained when the phase difference is −90 °.

  Next, the vibration isolating unit according to the present embodiment using such a vibrator as a drive source will be described with reference to FIGS. FIG. 4 is an exploded perspective view showing a configuration example of the vibration isolation unit of the present embodiment, and FIG. 5 is a schematic bottom view of the vibration isolation unit showing the simplified shape of each part shown in FIG. 6 is a schematic front view showing the X-axis drive mechanism portion extracted in FIG. 5, FIG. 7 is a cross-sectional view taken along the line AA in FIG. 6, and FIG. 8 is the X-axis in FIG. FIG. 9 is a schematic bottom view showing the drive mechanism portion extracted and enlarged, FIG. 9 is a cross-sectional view taken along line BB in FIG. 8, FIG. 10 is a plan view showing a pressing member, and FIG. FIG. 12 is a schematic front view showing an extracted Y-axis drive mechanism in FIG. 5, FIG. 12 is a cross-sectional view taken along the line CC in FIG. 11, and FIG. 13 is a cross-sectional view taken along the line DD in FIG. FIG.

  First, the vibration isolation unit 300 of the present embodiment is a final moving object that moves the holder 38 on which the CCD 31 is mounted in the X axis direction and the Y axis direction together with the optical LPF 32, the dust filter 33, and the like. An X frame 301 having a frame shape having a frame portion 301b surrounding an opening 301a around the photographing optical axis and having a desired size so that the holder 38 can be moved in the Y-axis direction, and an opening 302a around the photographing optical axis A frame (fixing member) 302 that has a frame shape having a frame portion 302b that surrounds the X frame 301, is formed in a desired size so as to be movably mounted in the X-axis direction, and is fixed to a camera body (not shown). .

  An X-axis drive mechanism 310x that moves the X frame 301 in the X-axis direction relative to the frame 302 and a Y-axis drive mechanism 310y that moves the holder 38 in the Y-axis direction relative to the X frame 301 are provided. By moving the holder 38 together with the X frame 301 in the X-axis direction relative to the frame 302 and moving the holder 38 in the Y-axis direction relative to the X frame 301, the CCD 31 mounted on the holder 38 can be moved in the XY plane. It is displaced so as to compensate for blurring in the axial direction and the Y-axis direction.

  Here, the configuration of the X-axis drive mechanism 310x will be described. The X-axis drive mechanism unit 310x includes an X-axis vibrator (first vibrator) 320x and a moving body (first moving body) 311x that is fixed to the X frame 301 and is driven together with the X frame 301. A sliding body 330x to be configured and a pressing mechanism 340x for biasing the X-axis vibrator 320x toward the sliding body 330x (moving body 311x) are provided.

  The X-axis vibrator 320x is a rectangular piezoelectric body having drivers (drive units) 321x and 322x that generate elliptical vibration when a predetermined frequency voltage is applied in accordance with the operating principle of the vibrator 200 described in FIG. Provided on one side of 323x. The X-axis vibrator 320x has a vibrator holder 324x at a central position on the side opposite to the driver elements 321x and 322x of the piezoelectric body 323x, and a protrusion 325x formed on the vibrator holder 324x is as shown in FIG. By fitting in the groove 342x (first holding portion) of the frame 302, the X-axis vibrator 320x is positioned and held so that movement in the X-axis direction is restricted. With such a configuration, the driving force due to elliptical vibration generated in the driver elements 321x and 322x acts in the X-axis direction.

  The sliding body 330x is formed by fixing a sliding plate 332x on a bearing 331x. The bearing 331x is fixed so as to be integrated with a part of the X frame 301 by a screw or the like at a position where the driver elements 321x and 322x of the X-axis vibrator 320x are pressed and contact the sliding plate 332x. Note that the fixing of the sliding body 330x to the X frame 301 is not limited to screwing, but may be bonding or the like, and the fixing method is not particularly limited. Here, as is apparent from FIG. 4, the sliding body 330x is formed with a size smaller than the X frame 301 formed in a desired size (a size corresponding to the X-axis vibrator 320x). Is. Further, the X frame 301 is formed of a resin material having low rigidity, aluminum, or the like, whereas the sliding plate 332x is formed of a material such as ceramic having high wear resistance and high rigidity, and a bearing 331x. Is obtained by quenching a quenchable material such as ferritic stainless steel to increase rigidity.

  The frame 302 includes a bearing 304x that is disposed at an opening-shaped attachment portion formed on the frame 302 and is fixed with a screw 303x so as to face the bearing 331x of the sliding body 330x. As shown in FIG. 9, a V-groove 305x along the X-axis direction is formed on the bearing 304x by adhering a V-groove plate 306x for preventing wear. As shown in FIG. 9, the bearing 331x has a V-groove 334x (V-groove plate 337x) facing the V-groove 305x (V-groove plate 306x) of the bearing 304x. Here, by inserting the two balls 336x positioned by the retainer 335x between the V-grooves 305x and 334x, the bearings 304x and 331x have two balls 336x arranged in one row along the X-axis direction. It is set as the structure which has. As shown in FIG. 4 and the like, the two balls 336x are positioned in the vicinity of the positions immediately below the driver elements 321x and 322x, and movement in the X-axis direction is restricted by the retainer 335x. The rolling elements are not limited to balls, and may be rollers.

  The pressing mechanism 340x includes a pressing plate (pressing member) 341x and a pressing spring (pressurizing means) 342x. The pressing plate 341x is disposed on the transducer holder 324x side of the X-axis transducer 320x (on the side opposite to the driver elements 321x and 322x contacting the sliding plate 332x) and is longer than the length of the X-axis transducer 320x in the longitudinal direction. As shown in FIG. 10, it is a metal plate material formed in a shape having a longitudinal direction. The pressing plate 341x has a pressing portion 343x that comes into contact with the X-axis vibrator 320x via a vibrator holder 324x provided at a surface position corresponding to the vibration node of the X-axis vibrator 320x. Here, one end of the pressing plate 341x in the longitudinal direction is attached to the frame 302 by a screw 345x that passes through the reference hole 344x, and the pressing plate 341x is bent in the thickness direction (pressing direction) of the X-axis vibrator 320x. The other end in the longitudinal direction is attached to the frame 302 by a long screw 347x penetrating the long hole 346x.

  In addition, a pressing spring 342x is disposed between the head of the screw 347x and the pressing plate 341x at an end position which is the other end in the longitudinal direction of the pressing plate 341x on the side of the X-axis vibrator 320x. The biasing force that biases the X-axis vibrator 320x is set to act. That is, the pressing spring 342x is between the portion where the X-axis vibrator 320x and the sliding body 330x (moving body 311x) are in contact with the portion where the pressing plate 341x and the X-axis vibrator 320x are in contact (that is, the X axis The transducer 320x is disposed within the approximate thickness range. The pressing force by the pressing spring 342x is set to a very large force of about 15N (Newton).

  Further, between the pressing plate 341x and the screw 345x, a cylindrical spacer 348x having a size to be fitted in the reference hole 344x and an annular sheet 349x are interposed. The spacer 348x and the sheet 349x are made of a material soft with respect to the rigid pressing plate 341x, for example, the spacer 348x is made of synthetic resin, and the sheet 349x is made of silicon rubber and functions as a vibration damping member. By interposing the spacer 348x and the sheet 349x, one end side of the pressing plate 341x is held so as to be movable in the pressing direction while being positioned with respect to the frame 302.

  Similarly, between the pressing plate 341x and the screw 347x, a cylindrical spacer 350x having a size loosely fitted in the long hole 346x and annular sheets 351x and 352x disposed at both ends of the pressing spring 342x are interposed. ing. The spacer 350x and the sheets 351x and 352x are soft materials with respect to the pressing plate 341x having rigidity, for example, the spacer 350x is made of synthetic resin, and the sheets 351x and 352x are made of silicon rubber and function as a vibration damping member. By interposing the spacer 350x and the sheets 351x and 352x, the other end side of the pressing plate 341x is held so as to be movable only in the pressing direction while being positioned with respect to the frame 302. Further, by attaching both ends of the pressing plate 341x to the frame 302 with screws 345x and 347x, in-plane rotation is also prevented.

  The bearing 331x passes through the center of the ball 336x and can rotate around an axis parallel to the V-groove 334x. However, the bearing 331x is integrated with the X frame 301 and is separated from the bearing 331x in a direction different from the X-axis direction. One ball 307x is disposed between the frame 302 and the X frame 301 at the same position (position separated from the two balls 336x at an equal distance as shown in FIGS. 6 to 8). As shown in FIG. 7, the ball 307x is maintained in a state of being held in the recess by the urging force of the spring 308x locked between the frame 302 and the X frame 301 in the vicinity of the ball 307x. Are positioned so as to maintain an interval in the photographic optical axis (Z-axis) direction. Here, the urging force of the spring 308x only needs to maintain the clamping state of the ball 307x, and is set to be several steps weaker than the urging force of the pressing spring 347x. Accordingly, the moving body 311x including the X frame 301 and the sliding body 330x can move with respect to the frame 302 by three-point support with the two balls 336x and the one ball 307x. Also, as shown in FIGS. 6 to 8, the ball 307x is disposed on the opposite side of the ball 336x with the photographing optical axis and the opening 301a interposed therebetween, thereby separating the distance between the ball 307x and the ball 336x. Therefore, a stable three-point support structure can be obtained. As described above, according to the present embodiment, it is possible to guide the moving body 311x in the moving direction and to define the inclination with three balls, thereby enabling stable driving.

  On the other hand, the basic structure of the Y-axis drive mechanism 310y is the same as that of the X-axis drive mechanism 310x. The Y-axis drive mechanism 310y uses the X frame 301 as a fixing member instead of the frame 302, and uses the holder 38 as a moving object instead of the X frame 301. 38 is provided with a sliding body 330y constituting a moving body (second moving body) 311y to be driven. 11 to 13, the pressing mechanism (pressing plate, pressing spring) and related members in the Y-axis driving mechanism portion 310y are not shown, but the pressing mechanism 340x in the Y-axis driving mechanism portion 310y is omitted. Moreover, it is comprised similarly to a related member.

  In addition, the image stabilization unit 300 according to the present embodiment includes an X-axis gyro 350x that detects a blur around the X-axis (pitch in the pitch direction) of the body unit 100 and a blur around the Y-axis (a blur in the yaw direction) of the body unit 100. The Y axis gyro 350y that detects the) is disposed on the frame 302. In addition, a position detection sensor 353 including a Hall element 351 disposed on the frame 302 and a magnet 352 disposed on a part of the holder 38 so as to face the Hall element 351 is provided. Then, an anti-vibration control circuit 355 that controls the vibrator drive circuit 354 for the X-axis vibrator 320x and the Y-axis vibrator 320y based on signals from the X-axis gyro 350x, the Y-axis gyro 350y, and the position detection sensor 353 is provided. The image stabilization control circuit 355 executes a control operation in accordance with an instruction from the Bucom 50.

  Next, the operation of the X-axis drive mechanism 310x will be described. When a predetermined frequency voltage is applied to the X-axis vibrator 320x to generate elliptical vibrations in the driver elements 321x and 322x, the driver elements 321x and 322x of the X-axis vibrator 320x are slid by the strong biasing force of the pressing mechanism 340x. Since it is in pressure contact with 332x, the sliding body 330x is driven in the rotational direction of the elliptical vibration of the driver elements 321x and 322x.

  Here, the pressing spring 342x, which is a component of the pressing mechanism 340x according to the present embodiment, uses the bent end position of the pressing plate 341x, and the X-axis vibrator 320x and the sliding body 330x (moving body 311x). Is disposed between a portion where the pressure plate abuts and a portion where the pressing plate 341x and the X-axis vibrator 320x abut (that is, within a range corresponding to the thickness of the X-axis vibrator 320x). There is no increase in size in the thickness direction. In the case of an imaging apparatus as in this embodiment, the thickness in the direction of the photographing optical axis can be reduced.

  Further, although the pressing portion 343x of the pressing plate 341x is in contact with a portion corresponding to the vibration node of the X-axis vibrator 320x, when the X-axis vibrator 320x vibrates at a high frequency, The vibration is transmitted. Here, in the present embodiment, since synthetic resin spacers 348x and 350x and silicon rubber sheets 349x, 351x and 352x are interposed between the pressing plate 341x and the frame 302, X-axis vibration Even if the vibration of the child 320x is transmitted to the pressing plate 341x, transmission of vibration to the system subsequent to the frame 302 can be suppressed by attenuating the vibration with the spacers 348x, 350x and the sheets 349x, 351x, 352x. Further, the pressing plate 341x is positioned in the frame 302 via the spacers 348x and 350x and the sheets 349x, 351x and 352x and is held in a state of being movable only in the pressing direction. The urging force can be applied in a stable state to the X-axis vibrator 320x via the pressing plate 341x.

  At this time, since the pressing force applied to the X-axis vibrator 320x is strong, if the rigidity of the sliding plate 332x and the bearing 331x constituting the sliding body 330x is weak, as shown by the phantom line in FIG. The sliding plate 332x and the bearing 331x are bent by the pressing force, and the driving elements 321x, 322x and the sliding plate 332x come into contact with each other, and the operation becomes unstable or stops operating.

  In this respect, in the present embodiment, since the sliding plate 332x and the bearing 331x constituting the sliding body 330x have high rigidity, the pressing contact state between the driver 321x, 322x and the sliding plate 332x is stabilized, and elliptical vibration is caused. The accompanying driving force is reliably transmitted to the sliding plate 332x, and can be driven in the rotational direction of elliptical vibration with high efficiency. At this time, the sliding body 330x side having the sliding plate 332x is not in surface contact with the frame 302 but is in contact with the rolling method by the balls 336x at the bearings 331x and 304x portions, so even if the pressing force is strong. The sliding body 330x moves reliably with little friction with respect to the frame 302. Since the bearings 331x and 304x have a single-row ball bearing structure along the X-axis direction, the sliding body 330x moves only in the X-axis direction when driven by the X-axis vibrator 320x. When the sliding body 330x moves in this way, the X frame 301 to which the sliding body 330x is fixed also moves in the X-axis direction integrally with the sliding body 330x. In other words, the moving direction of the X frame 301 is also guided by the engagement between the bearings 331x and 304x having a ball bearing structure of one row along the X axis direction.

  In such an operation, the bearing 331x passes through the center of the ball 336x and can rotate around an axis parallel to the V-groove 334x. However, the bearing 331x is integrated with the X frame 301, and the X-axis direction from the bearing 331x is One ball 307x is disposed between the frame 302 and the X frame 301 at different positions in different directions, and the moving body 311x composed of the X frame 301 and the sliding body 330x has two balls with respect to the frame 302. 336x and one ball 307x are supported at three points at a distance from each other, so that the frame 302 can be stably moved in the X-axis direction without causing a rotation due to rotation around an axis parallel to the V-groove 334x. Moving. Therefore, the guide support mechanism for the strong pressing portion with respect to the X-axis vibrator 320x may be a single-row ball bearing bearing structure along the X-axis direction by the bearings 331x and 304x, and the size and structure can be simplified.

  The Y-axis drive mechanism 310y operates in the same manner as the X-axis drive mechanism 310x.

  The present invention is not limited to the embodiment, and various modifications can be made without departing from the spirit of the present invention.

(Modification 1)
FIG. 15 is a schematic bottom view showing the X-axis drive mechanism portion of Modification 1 extracted and enlarged, and FIG. 16 is a cross-sectional view taken along line EE in FIG. In the first modified example, an annular sheet 353x made of, for example, silicon rubber is interposed as a vibration damping member between the pressing plate 341x and the frame 302 with respect to the attachment portion of the pressing plate 341x by screws 345x. Thus, the pressing plate 341x is held between the sheets 349x and 353x on one end side and held in a pressure contact state. Here, if the sheet 353x is made of a hard member, the pressing plate 341x cannot move in the pressing direction, thereby hindering the pressing operation. However, since the sheet 353x is made of a soft member such as silicon rubber, the urging force by the pressing spring 342x is not sufficient. In the case of the action, the depression is caused by the pressing by the pressing plate 341x, so that the pressing of the X-axis vibrator 320x by the pressing portion 343x is not hindered.

  In the first modification, a vibration damping sheet (second vibration damping member) 354x is attached to part of the pressing plate 341x. The vibration damping sheet 354x is made heavy while maintaining flexibility, for example, by mixing tungsten powder in rubber. Even if the vibration of the X-axis vibrator 320x is transmitted and vibration is generated in the pressing plate 341x, the vibration can be suppressed by attaching the vibration damping sheet 354x having a weight. Such a vibration damping sheet 354x may be provided on the upper surface of the pressing plate 341x, or may be provided entirely or partially.

  A vibration damping sheet (second vibration damping member) 355x that can suppress vibration is an example in which the vibration damping sheet (second vibration damping member) 355x is attached to the pressing portion 343x of the pressing plate 341x. Here, on the X-axis vibrator 320x side corresponding to the pressing part 343x, there is a convex part 326x (see FIG. 6) on the top of the vibrator holder 324x, and the vibration damping sheet 355x is in pressure contact with the convex part 326x. Become. Therefore, when the pressing plate 341x is assembled, the planar vibration damping sheet 355x comes into pressure contact with the convex portion 326x, so that a depression is generated in the vibration damping sheet 355x according to the shape of the convex portion 326x. Positioning with the part 343x will be made.

(Modification 2)
FIG. 17 is a schematic bottom view showing the X-axis drive mechanism portion of Modification 2 extracted and enlarged. In the second modification, both end sides of the pressing plate 341x are bent, and a pressing spring (pressurizing means) 356x is arranged on one end side, so that the supporting pressing structures at both ends are the same. That is, between the pressing plate 341x and the screw 357x, a cylindrical spacer 358x having a size to be fitted in the reference hole 344x and annular sheets 359x and 360x disposed at both ends of the pressing spring 356x are interposed. Yes. The spacer 358x and the sheets 359x and 360x are soft materials with respect to the rigid pressing plate 341x, for example, the spacer 358x is made of synthetic resin, and the sheets 359x and 360x are made of silicon rubber and function as a vibration damping member. By interposing the spacers 358x and the sheets 359x and 360x, one end side of the pressing plate 341x is held so as to be movable only in the pressing direction while being positioned with respect to the frame 302. In this way, the pressing plate 341x can apply a more stable pressing force to the X-axis vibrator 320x by applying an urging force by the pressing springs 342x and 356x at both ends of the pressing plate 341x.

(Modification 3)
FIG. 18 is a schematic bottom view showing the X-axis drive mechanism portion of Modification 3 extracted and enlarged. In the third modification, instead of the screws 345x and 347x, stepped screws 361x and 362x capable of positioning in the screwing direction are used, and rubber spacers 363x and 364x made of, for example, silicon rubber are provided around the stepped screws 361x and 362x. It is interposed as a vibration damping member. In the case of the modified example 3, the same operational effects as in the case of the present embodiment are also obtained.

(Modification 4)
FIG. 19 is a schematic bottom view showing the X-axis drive mechanism portion of Modification 4 extracted and enlarged. In Modification 4, for example, in the configuration of Modification 3, pressure means using permanent magnets 365x and 366x is arranged in place of the pressing spring 342x. The permanent magnets 365x and 366x have an annular shape coaxially arranged around the rubber spacer 364x at the end of the pressing plate 341x, and the heads of the stepped screws 362x have the same polarity as the opposing magnetic poles. And a pressing plate 341x to apply a biasing force due to a repulsive force. In the case of the modified example 4, the same operational effects as in the case of the present embodiment are also obtained. In addition, the structure using the attractive force of the magnets by making the opposite polarity magnetic poles face each other may be used.

It is a block diagram which shows roughly the electric system structure mainly of the camera of this Embodiment. It is a vertical side view which shows the structural example of an imaging unit. It is a schematic diagram which shows the operation | movement principle of a vibrator | oscillator. It is a disassembled perspective view which shows the structural example of the vibration isolator of this Embodiment. It is a schematic bottom view of the vibration isolator which shows the shape of each part shown in FIG. 4 in a simplified manner. It is a schematic front view which extracts and shows the X-axis drive mechanism part in FIG. It is the sectional view on the AA line in FIG. FIG. 6 is a schematic bottom view showing an X-axis drive mechanism portion in FIG. 5 extracted and enlarged. It is the BB sectional view taken on the line in FIG. It is a top view which shows a pressing member. It is a schematic front view which extracts and shows the Y-axis drive mechanism part in FIG. It is CC sectional view taken on the line in FIG. It is the DD sectional view taken on the line in FIG. It is explanatory drawing which shows a mode that bending arises with the pressing force with respect to a vibrator | oscillator. FIG. 10 is a schematic bottom view showing an X-axis drive mechanism portion of Modification 1 extracted and enlarged. It is the EE sectional view taken on the line of FIG. It is a schematic bottom view which expands and shows the X-axis drive mechanism part of the modification 2. It is a schematic bottom view which extracts and expands and shows the X-axis drive mechanism part of the modification 3. It is a schematic bottom view which extracts and expands and shows the X-axis drive mechanism part of the modification 4.

Explanation of symbols

31 CCD
301 X frame 302 Frame 311x, 311y Moving body 320x X-axis vibrator 320y Y-axis vibrator 326x Protruding part 341x Press plate 342x Press spring 343x Press part 348x Spacer 349x Sheet 350x Spacer 351x, 352x, 353x Sheet 354x35 Sheet 354x35 356x Pressure spring 358x Spacer 359x, 360x Sheet 363x, 364x Rubber spacer 365x, 366x Permanent magnet

Claims (2)

A vibrator in which elliptical vibration is generated in the drive unit by applying a predetermined frequency voltage signal;
A fixing member for holding the vibrator,
A moving body that is moved by elliptical vibration generated in the driving unit when the driving unit of the vibrator is pressed;
A plate-shaped pressing member for pressing the front Symbol transducer to the movable body,
Pressure means for urging the pressing member toward the vibrator via a vibration damping member at at least one of one end and the other end in the longitudinal direction of the pressing member ;
A position corresponding to a vibration node of the vibrator, which is affixed to the pressing member at a position opposite to the side where the vibrator and the moving body abut, and is in contact with the vibrator. A vibration damping member;
Driving apparatus characterized by comprising a.   The driving device according to claim 1, wherein the pressing member is held movably in a pressing direction while being positioned with respect to the fixed member via the vibration damping member.

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