JP2008092742A - Actuator device and image pick-up device for optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: an outer diameter is 4 mm or less and too small, as a rotating magnet of an actuator device of an optical device, to tighten with a tightening device such as press-fit, using an inner surface of the rotating magnet. <P>SOLUTION: This actuator device includes a rotating arm 102 which is rotated integrally with the rotating magnet, a driving pin 103 which is provided at the rotating arm, and a base member 72 which rotatably supports the rotating magnet. A fitting hole 165 in which one edge of the rotating magnet 101 in an axial direction is fitted is provided in the rotating arm 102, a support shaft 104 is provided at the base member 72, and a gap between the support shaft and the support hole of the rotating arm is made smaller than a gap between the support shaft and the hole in the axial direction, thus preventing the support shaft from being brought into contact with the hole in the axial direction when the rotating magnet is rotated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an actuator device of an optical device that moves an optical member in and out of an optical path by using magnetic force, and an imaging device including the actuator device, and in particular, a cylindrical rotation that constitutes a main component of the actuator device. The present invention relates to an actuator device and an imaging device of an optical device that can hold a magnet with high accuracy.

  As a conventional actuator device of this type of optical device, for example, there is one described in Patent Document 1. Patent Document 1 describes an electromagnetic actuator that generates a driving force by an electromagnetic force, and relates to an electromagnetic actuator that is applied when driving a shutter blade of a camera and a camera shutter device using the same. Yes. The electromagnetic actuator disclosed in Patent Document 1 includes a rotor having an outer peripheral surface divided in a circumferential direction and alternately magnetized with different magnetic poles and having a drive pin formed to protrude from the outer peripheral surface; And a yoke having a first magnetic pole portion and a second magnetic pole portion that have a circular arc surface facing the outer peripheral surface of the rotor and that generate different magnetic poles when energized to the coil. An electromagnetic actuator that rotates a range and outputs a driving force from the driving pin, wherein the rotor projects radially outward from the outer peripheral surface and is magnetized to the same magnetic pole as the outer peripheral surface, and It has a protruding portion formed so as to be opposed to the first magnetic pole portion and the second magnetic pole portion ”.

According to the electromagnetic actuator described in Patent Document 1 having such a configuration, “the first magnetic pole portion of the yoke, which is magnetized to the same magnetic pole as the outer peripheral surface and protruding radially outward from the outer peripheral surface of the rotor,” Providing the protruding portion formed so as to be opposed to the second magnetic pole portion increases the surface facing the yoke as a whole of the rotor, thereby achieving a desired holding force and driving torque while reducing the size. It is expected that the electromagnetic actuator that generates "(paragraph [0037] of the specification") can be provided.
JP 2004-194403 A

2. Description of the Related Art Conventionally, an actuator device using a magnetic force of a magnet has been provided in order to move an optical member such as a shutter or a fixed diaphragm of the optical device. As a magnet for this actuator device, for example, a plastic magnet in which magnetic powder is mixed in plastic is generally used. This plastic magnet is excellent in moldability because it uses plastic as a main raw material, but has an insufficient point that the generated magnetic force is weak.
Therefore, in the conventional optical device, it is necessary to increase the diameter of the plastic magnet in order to increase the magnetic force to a predetermined value. As a result, the entire optical device has been increased in size, and an imaging apparatus using the optical device has also been increased in size.

On the other hand, in recent years, permanent magnets using neodymium compounds and samarium compounds that are capable of generating a strong magnetic force while being small have been developed and used as magnet materials.
In this case, a permanent magnet using a neodymium compound or a samarium compound is formed by sintering. Therefore, a permanent magnet manufactured by sintering (hereinafter referred to as “sintered magnet”) preferably has a simple shape in view of formability. The simple shape in this case is a column or cylinder, and if it is a column or cylinder, it can be manufactured relatively easily by sintering.

  Thus, when the sintered magnet is formed in a cylindrical shape and used as an actuator device of an optical device, the following problems may occur. FIG. 17 is a cross-sectional view of a cylindrical rotating magnet 200 that can be used in this type of actuator device. The rotating magnet 200 is generally formed as a cylindrical body having a small diameter (for example, the outer diameter φA is 4 mm or less). When the outer diameter φA of the rotating magnet 200 is about 4 mm, the outer peripheral surface can be polished, so that the accuracy of the outer surface can be obtained to some extent. For example, a tolerance of about ± 0.03 mm is possible. It is. Therefore, if the rotating magnet has a highly accurate outer surface, the outer surface can be fastened sufficiently by fastening means such as press fitting.

  However, in the case of the inner diameter φB of the rotating magnet 200, since polishing is impossible, the accuracy of the inner surface cannot be obtained, and the tolerance is about ± 0.08 mm. . This is because the inner surface of the axial hole 201 of the rotating magnet 200 is extremely hard without being baked during sintering. Therefore, there is a problem that a rotating magnet having an inner surface with low accuracy cannot be fastened by fastening means such as press-fitting using the inner surface.

  The problem to be solved is that when a cylindrical magnet is used as the rotating magnet used in the actuator device of the optical device, especially when the outer diameter of the rotating magnet is as small as 4 mm or less. The inner surface of the dynamic magnet cannot be fastened by fastening means such as press fitting, and when the outer surface with high accuracy is used, it can be fastened by fastening means such as press fitting.

  The actuator device of the optical device according to the present invention corresponds to the core disposed outside the optical path of the optical device, the coil wound around the core, and the direction of the magnetic field output from the core by energizing the coil. A cylindrical rotary magnet having an axial hole that is pivoted in the axial direction and penetrates in the axial direction in the axial center portion, a rotary arm that is rotated integrally with the rotary magnet, and provided in the rotary arm And a base member that fixes and supports the core and rotatably supports the rotating magnet. An actuator device that moves an optical member in and out of an optical path by rotating a drive pin that is rotated based on rotation of a rotating magnet, and one end of the rotating magnet in the axial direction is fitted to the rotating arm. The base member or the pivot arm is provided with a support shaft that penetrates the axial hole, and the support shaft and the support hole of the pivot arm that supports the support shaft or the support hole of the base member are provided. The main feature is that the gap is made smaller than the gap between the support shaft and the axial hole so that the support shaft does not contact the axial hole when the rotating magnet rotates.

  An imaging device according to the present invention includes an imaging device attached to a lens barrel, a photographing optical system that is held inside the lens barrel and guides an image from a subject to the imaging device, and an optical path of the photographing optical system. And an actuator device that allows an optical member to be taken in and out. The actuator device is rotated in a direction corresponding to the direction of the magnetic field output from the core by energizing the coil, the coil wound around the core disposed outside the optical path of the optical device, and the coil. A cylindrical rotating magnet having an axial hole penetrating in the axial direction in the axial center portion, a rotating arm rotated integrally with the rotating magnet, a drive pin provided on the rotating arm, and a core And a base member that rotatably supports the rotating magnet. The pivot arm is provided with a fitting hole into which one end of the pivot magnet in the axial direction is fitted, and the base member or the pivot arm is provided with a support shaft that penetrates the axial hole. The gap between the support hole of the rotating arm to be supported or the support hole of the base member is made smaller than the gap between the support shaft and the axial hole. The optical member is moved in and out of the optical path by the rotation of the drive pin that is rotated based on the rotation of the rotation magnet.

  According to the actuator device and the imaging device of the optical device of the present invention, a cylindrical rotating magnet used for the actuator device can be manufactured relatively easily. In particular, by using a neodymium compound or a samarium compound as the main raw material of the rotating magnet, an actuator device having a rotating magnet having a strong magnetic force while being small in size can be obtained. For this reason, it is possible to reduce the size of the entire optical device using this actuator device, and to further reduce the size and weight of an imaging device using the optical device.

  The rotating magnet is formed in a cylindrical shape, a fitting hole is provided in the rotating arm, a support shaft is provided in the base member or the rotating arm, and the supporting shaft or the supporting hole of the rotating arm that supports the supporting shaft is provided. The clearance between the support hole of the member is made smaller than the clearance between the support shaft and the axial hole of the rotating magnet so that the support shaft does not contact the axial hole when the rotating magnet rotates. Thus, an actuator device and an imaging device of an optical device that can generate a large magnetic force while being a small rotating magnet and can contribute to a reduction in size and weight of the entire device have been realized with a simple configuration.

  For example, with reference to the outer diameter of the rotating magnet, a clearance that does not cause the tolerance of the inner diameter is opened, and the rotating magnet is integrally fixed to the rotating arm. And it is made to slide with the support shaft provided in the base member which is a base plate, and the bearing hole of a rotation arm so that a support shaft may not contact the inner surface of a rotation magnet. Further, the rotation magnet is integrally fixed to the rotation arm with a sufficiently large clearance so that the inner surface of the rotation magnet does not hit the support shaft provided on the base member. Then, the support shaft is slid between the bearing hole of the rotation arm and the bearing hole of the bearing lid so that the support shaft does not contact the inner surface of the rotation magnet.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 17 illustrate examples of embodiments of the present invention. That is, FIG. 1 is a perspective view of a digital still camera in a lens barrel storage state showing a first embodiment of an image pickup apparatus of the present invention, FIG. 2 is a perspective view of a lens barrel extended state, and FIG. FIG. 4 is a longitudinal sectional view of the lens barrel, FIG. 5 is a block diagram showing a schematic configuration of the digital still camera, and FIG. 6 is a perspective view showing a first embodiment of the actuator device of the present invention. FIG. 7 is an explanatory view showing a state in which a rotating magnet is arranged on the core body, FIG. 8 is a plan view of a base member of the actuator device, and FIG. 9 is a perspective view showing a first embodiment of the rotating magnet. 10 is a sectional view of the actuator device, FIG. 11 is an exploded perspective view, FIG. 12 is a perspective view of the core and the coil, and FIG. 13 is a plan view of the core and the coil. 14 is a plan view showing a second embodiment of the core and the coil, FIG. 15 is a cross-sectional view showing a second embodiment of the rotating arm and the supporting shaft, and FIG. 16 is a rotating arm and the supporting shaft. Sectional drawing which shows the 3rd example of this, FIG. 17 is a figure explaining a cylindrical rotation magnet.

  First, the digital still camera 1 according to the imaging apparatus of the present invention will be described. A digital still camera 1 shown in FIGS. 1 to 4 shows a first embodiment of an imaging apparatus of the present invention provided with an actuator device of an optical apparatus of the present invention described later. The digital still camera 1 uses a semiconductor recording medium as an information recording medium, converts an optical image from a subject into an electrical signal by an image pickup device such as a CCD or a CMOS, and records it on the semiconductor recording medium. The display can be displayed on the flat display panel 4 which is a display device such as a liquid crystal display.

  The digital still camera 1 is output from a lens barrel 3 that takes an image of a subject as light and guides it to an imaging device, a camera case 2 in which the lens barrel 3 and other devices and devices are built, and an imaging device. A flat display panel 4 that is a display device including a liquid crystal display or the like that displays an image based on a video signal, a control device that controls the operation of the lens barrel 3, display of the flat display panel 4, and the like, and a battery power source (not shown) Etc. are provided.

  The camera case 2 is formed of a horizontally long flat container, and includes a front case 5 and a rear case 6 that are overlapped in the front-rear direction, and a substantially rectangular frame interposed between the front case 5 and the rear case 6. The center case 7 is formed. A ring-shaped decorative ring 8 is attached to the front surface of the front case 5 at a position slightly deviated to one side from the center, and 1 on the front side of the lens barrel 3 is attached to the central hole 8a of the decorative ring 8. The group ring etc. are facing advancing and retreating.

  FIG. 1 shows a non-photographing state (lens barrel storage state) of the lens barrel 3, and the entire front surface of the lens barrel 3 is configured to be substantially flush with the front surface of the front case 5. Yes. FIG. 2 shows the photographing state (the extended state) of the lens barrel 3, in which the decorative ring 10 that encloses the first group ring and the decorative ring 11 that encloses the straight ring are extended in a nested state.

  A light emitting unit 12 of a flash device and a light emitting / receiving unit 13 of an autofocus mechanism are provided at an oblique upper portion of the lens barrel 3 of the front case 5. Further, on the upper surface of the center case 7, a power button 14, a shutter button 15, a sound collecting hole 16 of a sound collecting device such as a microphone, and the like are provided. In addition, a battery storage portion in which a battery as a power source is detachably stored is provided on one side surface portion of the center case 7, and a battery lid 17 is detachably engaged with the battery storage portion. Yes. A speaker hole 18 for a speaker device is provided on the side surface of the center case 7 opposite to the battery lid 17.

  A display window 21 is greatly opened in the rear case 6, and the flat display panel 4 is attached to the display window 21. The flat display panel 4 has a touch operation function that can be operated by a user touching the display surface. Various operation switches are provided on one side of the flat display panel 4 of the rear case 6. As operation switches, for example, a mode switching switch 22 for selecting a function mode (still image, moving image, reproduction, etc.), an optical zoom operation button 23 for executing a zoom operation, a menu button 24 for selecting various menus, and a screen The display switching button 25 for switching the display can be used, but a direction key for moving a cursor for selecting a menu, a screen button for switching the screen size, and deleting the screen can also be provided.

  A control device that drives and controls the lens barrel 3, the flat display panel 4, and the like is built in the camera case 2 having such a configuration. The control device is configured, for example, by mounting a predetermined microcomputer, a resistor, a capacitor, or other electronic components on a wiring board.

  FIG. 4 is an explanatory view showing the lens barrel 3 in the retracted state by cross-sectioning in the vertical direction. The lens barrel 3 includes a fixed ring 31 fixed to the camera case 2 inside the camera case 2, a movable ring 32 rotatably supported by the fixed ring 31, and photographing optics held by these. A system 33 and the like are provided. At the rear of the lens barrel 3, an image sensor 28 composed of a CCD, a CMOS sensor, or the like that images a subject image formed by the photographing optical system 33 is disposed. Image data is generated based on the imaging signal output from the imaging element 28, and the image data is supplied to each unit of the digital still camera 1.

  The imaging optical system 33 of the lens barrel 3 is optically a three-group lens configuration, and includes a first-group lens 34 that is a combination of a plurality of lenses arranged in order from the subject side, and a combination of a plurality of lenses. The second group lens 35, the third group lens 36 composed of a combination of one or two or more lenses, and a low-pass filter (not shown). The first group lens 34 is held by a first group lens frame 37, the second group lens 35 is held by a second group lens frame 38, and the third group lens 36 is held by a third group lens frame 39. The actuator device 60 according to the present invention is attached to the second group lens frame 38.

  In this photographing optical system 33, a zooming function is exhibited by the first group lens 34 and the second group lens 35. By moving the first group lens 34 and the second group lens 35 by a predetermined amount in the optical axis direction, a zooming operation of the optical system is performed. Can be executed. Further, the focusing function is exhibited by the third group lens 36, and the focusing operation of the optical system can be executed by moving the third group lens 36 by a predetermined amount in the optical axis direction.

  FIG. 5 is a block diagram illustrating a first example of a schematic configuration of the digital still camera 1 including the lens barrel 3. The digital still camera 1 includes a lens barrel 3, a video recording / reproducing circuit unit 41 that plays a central role of a control device, a program memory, a data memory, and the like for driving the video recording / reproducing circuit unit 41. A built-in memory 42 having a RAM, a ROM, and the like, a video signal processing unit 43 that processes captured images and the like into predetermined signals, a flat display panel 4 that displays captured images and the like, and an external that expands the storage capacity A memory 44 and a lens barrel control unit 45 for driving and controlling the lens barrel 3 are provided.

  The video recording / reproducing circuit unit 41 includes, for example, an arithmetic circuit having a microcomputer (CPU). The video recording / reproducing circuit unit 41 is connected with a built-in memory 42, a video signal processing unit 43, a lens barrel control unit 45, a monitor driving unit 46, an amplifier 51, and two interfaces (I / F) 48 and 49. Yes. The video signal processing unit 43 is connected to the image sensor 28 attached to the lens barrel 3 via an amplifier 51. A signal processed into a predetermined video signal by the video signal processing unit 43 is input to the video recording / reproducing circuit unit 41.

  The flat display panel 4 is connected to the video recording / reproducing circuit unit 41 via the monitor driving unit 46. A connector 52 is connected to the first interface (I / F) 48, and an external memory 44 can be detachably connected to the connector 52. A connection terminal 53 provided in the camera case 2 is connected to the second interface (I / F) 49. The lens barrel control unit 45 is connected to a lens driving unit 54 that drives and controls the lens barrel 3 and a position sensor 55 that detects the amount of rotation of the lens barrel 3 and the amount of movement in the optical axis direction. ing.

  Thus, when an image of the subject is input to the imaging optical system 33 of the lens barrel 3 and formed on the imaging surface of the image sensor 28, the image signal is input to the video signal processing unit 43 via the amplifier 51. The A signal processed by the video signal processing unit 43 into a predetermined video signal is input to the video recording / reproducing circuit unit 41. As a result, a signal corresponding to the subject image is output from the video recording / reproducing circuit unit 41 to the monitor driving unit 46, the built-in memory 42 or the external memory 44. As a result, an image corresponding to the image of the subject is displayed on the flat display panel 4 via the monitor driving unit 46, or is recorded as an information signal in the built-in memory 42 or the external memory 44 as necessary.

  Next, the outline of the actuator device 60 will be described first, and then the configuration and operation of the actuator device 60 will be described in detail. As shown in FIG. 6, the actuator device 60 attached to the second group lens frame 38 of the lens barrel 3 includes three actuators including a first actuator 61, a second actuator 62, and a third actuator 63. It is prepared for.

  The first to third actuators 61 to 63 are configured to put in and out the optical member with respect to the optical path SL of the photographing optical system 33. In this embodiment, the first actuator 61 moves the fixed aperture 65 in and out of the optical path SL. The second actuator 62 moves the ND filter 66 in and out of the optical path SL. The third actuator 63 moves the shutter blade 67 in and out of the optical path SL. Thereby, the light quantity adjustment of the optical path SL is performed by the fixed diaphragm 65 and the ND filter 66, and the optical path SL is opened and closed by the shutter blade 67.

  The first to third actuators 61 to 63 include yokes 68A, 68B, and 68C, a coil 69, rotating magnets 71A, 71B, and 71C, a base member 72, and the like. The three yokes 68 </ b> A, 68 </ b> B, 68 </ b> C are continuously formed at a predetermined interval in the circumferential direction, and are integrally configured as one yoke body 68. As shown in FIG. 7, the three yokes 68A, 68B, 68C are an inner portion 74 extending along the circumference of the optical path SL, and are located on the outer side farther from the optical path SL than the inner portion 74, and the inner portion. 74 and an outer portion 75 that extends opposite to the inner portion 74, and a connecting portion 76 that connects one end of the inner portion 74 and the outer portion 75 in the extending direction. The adjacent inner portion 74 and inner portion 74 are connected by a connecting portion 77.

  Further, the three yokes 68A, 68B, and 68C are configured by laminating one or more thin plate materials having magnetism. The number of the thin plate members is determined by a magnetic force that is strong enough to cause each optical member to appear and disappear in the optical path SL in accordance with the optical member that rotates. As a material of the yoke 68, for example, a silicon steel plate, an electromagnetic steel plate, a pure iron plate, a steel plate, or the like can be used. The yoke body 68 is attached to the base member 72 as shown in FIG. The base member 72 is formed as a ring-shaped member having a round hole 73 through which light passes. The base member 72 is provided with three support shafts 78A, 78B, 78C arranged at equal intervals in the circumferential direction so as to surround the round hole 73.

  Three rotating magnets 71 are rotatably fitted to the three support shafts 78A, 78B, 78C, respectively. The three rotating magnets 71A, 71B, 71C are arranged between the end portion of the inner portion 74 and the end portion of the outer portion 75 on the side opposite to the connecting portion 76 of the three yokes 68A, 68B, 68C. Each of the rotating magnets 71A, 71B, 71C has a cylindrical shape with a bearing hole 71a passing through the center. The rotating magnets 71A, 71B, 71C are respectively magnetized in the N pole and the S pole so as to be divided into two in the diameter direction, and rotate at a predetermined angle according to the polarities of the inner portion 74 and the outer portion 75. It is configured as follows. The inner portion 74 is provided with a concave curved surface 79a, and the outer portion 75 is provided with a concave curved surface 79b so as to widen the area facing the outer peripheral surface of the rotating magnets 71A, 71B, 71C. Is provided.

  Coils 81 are mounted on the inner portions 74 of the three yokes 68A, 68B, and 68C. The coil 81 may be mounted on the outer portion 75 of each yoke 68A, 68B, 68C. The coil 81 may be formed by winding a winding around a bobbin, or may be formed by winding an electric wire without having a bobbin and fixing it with an adhesive or the like. Good. By changing the direction of the current supplied to the coil 81, the inner part 74 can be a + (plus) pole and the outer part 75 can be a-(minus) pole. Conversely, the inner part 74 can be a-pole. A switching operation for changing the outer portion 75 to the positive pole can be performed.

  As shown in FIG. 6, of the three rotating magnets 71A, 71B, 71C rotatably supported by the three support shafts 78A, 78B, 78C, the first facing the first yoke 68A. One end of the arm portion 65a of the fixed diaphragm 65 is fixed to the rotating magnet 71A. By rotating the first rotating magnet 71A, the fixed diaphragm 65 is selectively set to a first position that coincides with the center of the optical path SL and a second position that is radially outward from the optical path SL. Can be moved to. One end of the arm portion 66a of the ND filter 66 is fixed to the second rotating magnet 71B opposed to the second yoke 68B. By rotating the second rotating magnet 71B, the ND filter 66 is selectively set to a first position that coincides with the center of the optical path SL and a second position that is radially outward from the optical path SL. Can be moved to.

  Further, one end of the shutter blade 67 is fixed to the third rotating magnet 71C opposed to the third yoke 68C. The shutter blade 67 is composed of a combination of two blade bodies 67a and 67b that can open and close the optical path SL, and is rotatably supported by a third support shaft 78C. Each blade body 67a, 67b is provided with a cam groove 83, and a cam pin 84 is slidably engaged with the cam groove 83. By moving the cam pin 84 by a blade opening / closing mechanism (not shown), the first blade blade 67a and 67b are brought close to each other to close the light path SL, and the two blade members 67a and 67b are moved away from each other to open the light path SL. It can be selectively moved to the second position.

  Next, details of the actuator device 60 will be described with reference to FIGS. 9 to 13 show a specific configuration of the first embodiment of the actuator device according to the present invention. The actuator device 100 includes a rotating magnet 101, a rotating arm 102, a drive pin 103, and a support shaft. 104, a core 105, a coil 106, and the like.

  As shown in FIGS. 9 to 11, the rotating magnet 101 is formed of a pipe-shaped hollow shaft body having a circular cross-sectional shape and having an axial hole 111 penetrating the axial center portion in the axial direction. The rotating magnet 101 is formed by sintering (sintered magnet). As a material of the rotating magnet 101, for example, a neodymium compound in which neodymium is used as a main raw material and iron or the like is added thereto, or a samarium compound in which samarium is used as a main raw material and cobalt or the like is added thereto is preferable.

  The outer diameter of the rotating magnet 101 is relatively large, for example, about 4 mm. In this case, the outer peripheral surface of the rotating magnet 101 can be polished. Therefore, the outer peripheral surface of the rotating magnet 101 is polished so that a predetermined tolerance (for example, ± 0.03 mm) is obtained with respect to a predetermined outer diameter. On the other hand, since the inner diameter of the rotating magnet 101 is as small as about 1 mm, for example, it cannot be polished. Therefore, the inner surface of the rotating magnet 101 is a sintered surface that has been sintered. In this case, the tolerance of the inner surface of the rotating magnet 101 is, for example, about ± 0.1 mm.

  The magnet 101 is magnetized in two directions of N and S with respect to a certain diameter direction. In FIG. 13, for example, with respect to the X axis perpendicular to the direction in which the two core pieces 105a and 105b extend. And can be rotated at an angle of ± 15 degrees. The magnetic spring generated between the core 105 and the core 105 is always held at an angular position of +15 degrees or −15 degrees even when no power is supplied. Further, by switching +/- in the energizing direction of the coil, the coil is displaced from the original position to the opposite position.

  The rotating arm 102 includes a bearing portion 161 formed in a cup shape, an arm portion 162 formed so as to protrude radially outward from the outer peripheral surface of the bearing portion 161, and a shaft from the center of one surface of the bearing portion 161. And a pivot 163 formed so as to protrude in the direction. The bearing 161 has a disc shape, and a pivot 163 having an axial hole 164 penetrating in the axial direction is integrally provided in the center of one surface of the bearing 161. Furthermore, an annular groove continuous in the circumferential direction is provided on one surface of the bearing portion 161, and a fitting hole 165 for fixing one end of the rotating magnet 101 in the axial direction is formed by the annular groove. .

  A drive pin 103 that protrudes on the opposite side of the pivot 163 is provided on the surface opposite to the side from which the pivot 163 projects, which is the tip of the arm portion 162 of the rotating arm 102. The rotating magnet 101 and the rotating arm 102 are integrally configured by fitting one end of the rotating magnet 101 in the axial direction into the fitting hole 165 of the bearing portion 161. The coupling means of the rotating magnet 101 and the rotating arm 102 may be fixed by press-fitting one end of the rotating magnet 101 in the axial direction into the fitting hole 165, and an adhesive is applied to the fitting hole 165. Then, it may be fixed by bonding with an adhesive. As a material of the rotating arm 102, for example, an engineering plastic such as ABS or PC is suitable.

  A support shaft 104 is provided on the base member 72 in order to rotatably support the rotating arm 102. A seat portion 166 having a diameter approximately equal to the outer diameter of the rotating magnet 101 is provided at the base portion of the support shaft 104. The rotating arm 102 is rotated in contact with the seat 166. Now, assuming that the outer diameter and inner diameter of the rotating magnet 101 are M1 and M2, the outer diameter and inner diameter of the pivot 163 are S1 and S2, and the diameter of the support shaft 104 is D, M1> M2> S1> There is a relationship of S2> D. In this case, the gap Z2 between the inner diameter S2 of the pivot 163 and the diameter D of the support shaft 104 is sufficiently smaller than the gap Z1 between the inner diameter M2 of the rotating magnet 101 and the outer diameter S1 of the pivot 163. To be. At this time, considering that a variation of about ± 0.1 occurs in the inner diameter M2 of the rotating magnet 101, the gap Z1 is sufficiently escaped so that an appropriate clearance is provided.

  The core 105 is formed so that the planar shape is U-shaped, and two opposing core pieces 105a and 105b extend in parallel to each other. As a material of the core 105, for example, a silicon steel plate, an electromagnetic steel plate, a pure iron plate, a steel plate, or the like can be used. A coil 106 is attached to one core piece 105a.

  The coil 106 includes a bobbin 113 having a rectangular cross-sectional shape, and a coil wire 114 wound around the bobbin 113 by a predetermined number of turns. As shown in FIG. 12, one core piece 105 a of the core 105 is inserted into the center hole of the bobbin 113, and the bobbin 113 is fixed to the core 105 so that it cannot move. As shown in FIG. 13, the rotating magnet 101 is interposed between the two core pieces 105 a and 105 b of the core 105.

  As shown in FIG. 10, the rotating magnet 101 has the axial hole 11 directed in the vertical direction perpendicular to the plane direction of the base member (base plate) 72 by the support shaft 104 penetrating the axial hole 11. The base member 72 is rotatably supported. The base member 72 is provided with a long hole 116 through which the drive pin 103 integral with the rotating magnet 101 is inserted. The elongated hole 116 extends in an arc shape around the support shaft 104, and the radius of curvature is configured to be equal to the length from the support shaft 104 to the drive pin 103.

  The tip of the support shaft 104 is rotatably supported by a bearing bracket 121 that forms a part of the base member (base plate) 72. The bearing bracket 121 has a crank shape in which two portions in the longitudinal direction of a strip-shaped plate material are bent at 90 degrees. A bearing hole 122 is provided in one flat surface portion 121 a of the bearing bracket 121. The tip end portion of the support shaft 104 is fitted into the bearing hole 122 and is rotatably supported. The other flat surface portion 121 b of the bearing bracket 121 has an insertion hole 123 for screwing the bearing bracket 121 to the base member 72 and a positioning hole for positioning the bearing bracket 121 at a predetermined position of the base member 72. 124 is provided.

  A screw hole 117 is provided in the base member 72 so as to correspond to the insertion hole 123 of the bearing bracket 121. A positioning projection 118 is provided on the base member 72 corresponding to the positioning hole 124 of the bearing bracket 121. The positioning hole 124 is fitted into the positioning protrusion 118, the shaft portion of the fixing screw 125 is inserted into the insertion hole 123, and the screw shaft is screwed into the screw hole 117 and tightened. Thereby, the bearing bracket 121 is fastened and fixed to the base member 72.

  The base member 72 is provided with a support portion 131 for positioning and fixing the core 105 at a predetermined position. A support groove 132 that engages and supports an intermediate portion of the core 105 is provided on the upper surface of the support portion 131. By engaging and supporting the intermediate portion of the core 105 in the support groove 132, the rotating magnet 101 is interposed between the two core pieces 105a and 105b of the core 105 as shown in FIG. Yes. As a material for the base member 72 and the bearing bracket 121, for example, engineering plastics such as ABS and PC are suitable.

  Thus, in the state shown in FIG. 13, when one of the core pieces 105 a of the core 105 is N in the direction of the coil wire 114 of the coil 106 (for example, from the one end 114 a to the other end 114 b). When it becomes a pole and the other core piece 105b becomes an S pole, it coincides with the pole of the rotating magnet 101 facing those poles. As a result, repulsive forces are generated between the opposing poles, and the rotating magnet 101 rotates clockwise (or counterclockwise). As a result, the drive pin 103 provided on the rotation arm 102 integrated with the rotation magnet 101 rotates the same angle as the rotation magnet 101. By rotating the drive pin 103, a desired optical member, for example, the above-described fixed diaphragm or ND filter can be rotated to put it in and out of the optical path SL, or the shutter blade can be opened and closed.

  FIG. 14 shows a modified embodiment of the core 105 described above. The core 135 is provided with curved surfaces 136a and 136b on the inner surfaces of the two core pieces 135a and 135b facing the rotating magnet 101, so that the area facing the rotating magnet 101 is increased to increase the strength of the generated magnetic force. It is a thing.

  FIG. 15 shows a second example of the actuator device. The actuator device 170 is different from the actuator device 100 in that a rotating arm 171 is different and a bearing lid 172 is provided at one end of the rotating magnet 101 in the axial direction. Therefore, here, the difference between the rotating arm 171 and the rotating arm 102 and the bearing lid 172 will be mainly described, and the same portions will be denoted by the same reference numerals and overlapping description will be omitted.

  The rotation arm 171 is different from the rotation arm 102 in that the pivot 163 is removed. The rotating arm 171 includes a bearing portion 173 and an arm portion 174 similar to the bearing portion 161. One surface of the bearing portion 173 of the rotating arm 171 is provided with a fitting hole 175 formed of an annular groove continuous in the circumferential direction. A bearing hole 176 similar to the axial hole 164 of the pivot 163 is provided at the center of the bearing portion 173. Furthermore, a drive pin 103 that protrudes to one side is provided at the tip of the arm portion 174.

  The bearing lid 172 has substantially the same configuration as the bearing portion 173, and a fitting hole 175 formed of an annular groove continuous in the circumferential direction is provided on one surface thereof. In the center of the bearing lid 172, a bearing hole 178 similar to the bearing hole 176 is provided on the same axis. The bearing lid 172 is fitted and fixed integrally with one end of the rotating magnet 101 in the axial direction. The means for fixing the bearing lid 172 to the rotating magnet 101 is the same as that of the rotating arm 102 and may be press-fitted or may be joined using an adhesive. Other configurations are the same as those in the above embodiment.

  Now, the outer diameter and inner diameter of the rotating magnet 101 are M1 and M2, the diameters of the bearing hole 176 of the bearing portion 173 of the rotating arm 171 and the bearing hole 178 of the bearing lid 172 are S2 and S2, and the diameter of the support shaft 104 is D. Then, there is a relationship of M1> M2> S2> D between them. In this case, the gap Z2 between the diameter S2 of the bearing hole 178 and the diameter D of the support shaft 104 is sufficiently smaller than the gap Z1 between the inner diameter M2 of the rotating magnet 101 and the diameter D of the support shaft 104. To be. At this time, considering that a variation of about ± 0.1 occurs in the inner diameter M2 of the rotating magnet 101, the gap Z1 is sufficiently escaped so that an appropriate clearance is provided.

  FIG. 16 shows a third example of the actuator device. The actuator device 180 is different from the actuator device 100 in the structure of the rotating arm 181 and the support structure for supporting the rotating arm 181 on the base member 72. Therefore, here, these different points will be described with emphasis, and the same portions will be denoted by the same reference numerals and redundant description will be omitted. The rotating magnet 101 is the same as that of the above-described embodiment.

  The rotating arm 181 includes a support shaft 182, a bearing portion 183, and an arm portion 184. On one surface of the bearing portion 183 of the rotating arm 181, a fitting hole 185 is provided that is an annular groove continuous in the circumferential direction. A support shaft 182 extending in a direction orthogonal to the direction in which the arm portion 184 extends is provided at the center of the bearing portion 183. The support shaft 182 includes a first shaft portion 182a that protrudes from one surface of the bearing portion 183 in a first direction, and a second shaft that protrudes from the other surface of the bearing portion 183 in a second direction opposite to the first direction. The shaft portion 182b. In order to rotatably support both ends of the support shaft 182, the bearing bracket 121 is provided with a first boss portion 191, and the base member 72 is provided with a second boss portion 192. The two boss portions 191 and 192 are opposed so as to be positioned on the same axis.

  Now, assuming that the outer diameter and inner diameter of the rotating magnet 101 are M1 and M2, and the diameter of the support shaft 104 is D, there is a relationship of M1> M2> D. In this case, the gap Z2 between the diameter S2 of the bearing hole provided in the boss portions 191 and 192 and the diameter D of the support shaft 182 is a gap between the inner diameter M2 of the rotating magnet 101 and the diameter D of the support shaft 104. The value is made sufficiently smaller than Z1. At this time, considering that a variation of about ± 0.1 occurs in the inner diameter M2 of the rotating magnet 101, the gap Z1 is sufficiently escaped so that an appropriate clearance is provided.

  The same effects as those of the above-described embodiment can be obtained by adopting the configuration shown in FIGS. Incidentally, in the conventional actuator device of this type, the diameter of the magnet used for the rotating magnet is limited to about 3 mm. However, in the present invention, the diameter of the magnet is set to about 0.6 mm to 1.0 mm. It became possible to make it smaller. The main factors for this are considered to be (1) using a neodymium compound or samarium compound as a raw material for the magnet, (2) forming the shaft portion as a separate member, and then joining it. In general, sintered magnets (neodymium magnets or samarium magnets) are difficult to be formed into irregular shapes, and it is difficult to process them into a cylindrical shape in terms of cost (economic efficiency), accuracy, reliability, etc. It is preferable also from a point.

  The digital still camera 1 having the above-described configuration can be used as follows, for example. FIG. 1 shows a state in which the open / close spring of the lens barrier unit in the lens barrel 3 is closed and the optical lens system is closed, that is, a non-photographing state. In this case, the power of the digital still camera 1 is turned off. FIG. 2 shows a state in which the open / close spring of the lens barrier unit is opened and the optical lens system is opened, that is, a photographing enabled state. This photographing enabled state is automatically executed by operating the power button 14 to turn on the power. As a result, the digital still camera 1 changes from the form shown in FIG. 1 to the form shown in FIG.

  Thereafter, when the digital still camera 1 is ready to shoot, the photographic lens is pointed at the subject and the shutter button 15 is pressed, so that the subject can be photographed and the image can be captured. At this time, by operating the optical zoom operation button 23, the focal length is continuously changed according to the operation direction without changing the position of the image point, and the wide (wide angle) screen or the tele (telephoto) screen. Can be obtained.

  As described above, according to the present invention, the actuator device of the optical device can be made smaller than the conventional device and can generate high torque. Therefore, the shutter speed can be increased and the optical path of an optical component such as a fixed aperture and an ND filter can be taken in and out at a high speed.

  The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, an example in which a digital still camera is applied as the imaging device has been described. However, the present invention can also be applied to a digital video camera, a personal computer with a camera, a mobile phone with a camera, and other imaging devices. Furthermore, although the example using the third group lens as the optical lens has been described, it is needless to say that it may be a fourth group lens or more.

It is a perspective view of the lens barrel storage state of the digital still camera showing the first embodiment of the imaging apparatus of the present invention. It is a perspective view of a lens barrel extended state of a digital still camera showing a first embodiment of an imaging apparatus of the present invention. It is the perspective view which looked at the digital still camera which shows the 1st example of the imaging device of the present invention from the back. 1 is a longitudinal sectional view of a lens barrel suitable for use in a digital still camera showing a first embodiment of an imaging apparatus according to the present invention. 1 is a block diagram illustrating a schematic configuration of a digital still camera illustrating a first embodiment of an imaging apparatus according to the present invention. It is a perspective view which shows the 1st Example of the actuator apparatus of this invention. The 1st example of the actuator apparatus of this invention is shown, and it is explanatory drawing of the state by which the rotation magnet is arrange | positioned at the core body. The 1st Example of the actuator apparatus of this invention is shown, and it is a top view of the base member of an actuator apparatus. It is a perspective view which shows the 1st Example of the rotation magnet which concerns on the 1st Example of the actuator apparatus of this invention. It is sectional drawing of the actuator apparatus which shows the 1st Example of the actuator apparatus of this invention. It is a disassembled perspective view of the actuator apparatus which shows the 1st Example of the actuator apparatus of this invention. It is a perspective view of the core and coil which concern on the 1st Example of the actuator apparatus of this invention. It is a top view of the core and coil which concern on the 1st Example of the actuator apparatus of this invention. It is a top view of the core and coil which concern on the 2nd Example of the actuator apparatus of this invention. It is sectional drawing which shows the 2nd Example of the rotation arm which concerns on the 1st Example of the actuator apparatus of this invention. It is a disassembled perspective view which shows the 3rd Example of the rotation arm which concerns on the 1st Example of the actuator apparatus of this invention. It is sectional drawing explaining the cylindrical rotation magnet which concerns on the actuator apparatus of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Digital still camera (imaging device), 2 ... Camera case, 3 ... Lens barrel, 28 ... Imaging device, 33 ... Imaging optical system, 60, 100, 170, 180 ... Actuator device, 65 ... Fixed aperture (Optical member) , 66 ... ND filter (optical member), 67 ... shutter blade (optical member), 72 ... base member (base plate), 101 ... rotating magnet, 102, 171, 181 ... rotating arm, 103 ... drive pin, 104 , 182 ... support shaft, 105, 135 ... core, 106 ... coil, 111 ... axial hole, 121 ... bearing bracket, 122, 176, 178 ... bearing hole, 161, 173, 183 ... bearing part, 162, 174, 184 ... arm part, 165, 175, 177, 185 ... fitting hole, 172 ... bearing lid, 191, 192 ... boss part

Claims (7)

A core disposed outside the optical path of the optical device;
A coil wound around the core;
A cylindrical rotating magnet rotated in a direction corresponding to the direction of the magnetic field output from the core by energizing the coil and having an axial hole penetrating in the axial direction in the axial center portion;
A rotating arm that rotates integrally with the rotating magnet;
A drive pin provided on the pivot arm;
A base member that fixes and supports the core and supports the rotating magnet so as to be rotatable.
An actuator device that moves an optical member in and out of the optical path by rotation of the drive pin that is rotated based on rotation of the rotation magnet,
The rotation arm is provided with a fitting hole into which one end of the rotation magnet in the axial direction is fitted,
The base member or the pivot arm is provided with a support shaft that penetrates the axial hole,
The clearance between the support shaft and the support hole of the rotating arm that supports the support shaft or the support hole of the base member is made smaller than the clearance between the support shaft and the axial hole, and the rotation An actuator device for an optical device, wherein the support shaft does not contact the axial hole when the moving magnet rotates. The support shaft is provided on the base member,
The actuator device for an optical device according to claim 1, wherein the support hole is a cylindrical axial hole provided in a concentric manner with the fitting hole of the rotating arm. The support shaft is provided on the base member,
The support hole includes a first bearing hole provided concentrically with the fitting hole of the rotating arm, and a second bearing hole provided in a bearing lid fixed to one end in the axial direction of the rotating magnet. The actuator device for an optical device according to claim 1, comprising: The actuator device for an optical device according to claim 1, wherein the support shaft is provided on the rotating arm, and both ends of the support shaft in the axial direction are rotatably supported by the base member. The actuator device for an optical device according to claim 1, wherein the rotating magnet is formed by sintering with a sintered material having at least a magnetic material.   6. The actuator device for an optical device according to claim 5, wherein the rotating magnet is formed using a neodymium compound or a samarium compound as a main raw material. An image sensor attached to the lens barrel;
A photographing optical system that is held inside the lens barrel and guides an image from a subject to the image sensor;
An actuator device that allows an optical member to be taken in and out of the optical path of the imaging optical system,
The actuator device includes:
A core disposed outside the optical path of the optical device;
A coil wound around the core;
A cylindrical rotating magnet rotated in a direction corresponding to the direction of the magnetic field output from the core by energizing the coil and having an axial hole penetrating in the axial direction in the axial center portion;
A rotating arm that rotates integrally with the rotating magnet;
A drive pin provided on the pivot arm;
A base member that fixes and supports the core and supports the rotating magnet rotatably.
The rotation arm is provided with a fitting hole into which one end of the rotation magnet in the axial direction is fitted,
The base member or the pivot arm is provided with a support shaft that penetrates the axial hole,
The clearance between the support shaft and the support hole of the rotating arm that supports the support shaft or the support hole of the base member is made smaller than the clearance between the support shaft and the axial hole, and the rotation When the moving magnet rotates, the support shaft does not contact the axial hole.
An imaging apparatus, wherein an optical member is moved in and out of the optical path by rotation of the drive pin that is rotated based on rotation of the rotation magnet.

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