JP4952289B2 - DRIVE DEVICE, IMAGING UNIT, AND IMAGING DEVICE - Google Patents

Description

  The present invention relates to a driving technique for enlarging displacement generated in a driving unit.

  The driving device that moves the movable portion is used for, for example, an automatic focusing (AF) mechanism or a zoom mechanism in the photographing optical system of the imaging device. Conventionally, these drive devices employ a stepping motor or the like as the drive unit to drive the movable unit.

  By the way, in recent years, small electronic devices (for example, cellular phones) equipped with a micro camera unit (MCU) and added with a photographing function have been rapidly spread. Along with this, there is a strong demand for miniaturization of drive devices used in the AF mechanism or zoom mechanism for MCUs.

  However, in the above-described drive device using a stepping motor or the like for the drive unit, it is necessary to secure a specific space for the drive unit, and thus it is difficult to cope with downsizing.

  Therefore, in order to realize a reduction in the size of the drive unit, a drive device has been proposed in which a MEMS (Micro Electro Mechanical System) actuator manufactured by making full use of a semiconductor microfabrication technique is used in the drive unit (Patent Document 1). ).

JP 2006-133730 A

  Since the MEMS actuator does not need to secure a specific space, it can be reduced in size, but the displacement (drive displacement) that can be taken out by driving is reduced, and a large amount of movement cannot be secured in the movable part. There's a problem.

  Therefore, an object of the present invention is to provide a technique capable of ensuring a large amount of movement in a movable part even if the drive stroke of the drive part itself is small.

In order to solve the above problems, the invention of claim 1 is configured by using a frame material disposed on the outer peripheral side of a movable part to which a driven body is fixed and an elastic body, and the movable part and the frame material. a connecting member connecting the door, said frame member to a drive unit coupled respectively, the unit driving mechanism comprising a resilient member interposed between the fixed point and the frame member with respect to said movable portion A plurality of symmetrically provided drive displacements applied from the drive unit, by the lever action of the frame material with a coupling site with the elastic member as a fulcrum, resisting elastic deformation of the elastic member and the frame material and It is enlarged to displacement of the driven body via a connecting member, and when the movable part is driven in the same direction by a plurality of unit driving mechanisms, the connecting member of each unit driving mechanism is elastically deformed. Toss .

According to a second aspect of the present invention, in the drive device according to the first aspect of the present invention, among the drive units included in each of the plurality of unit drive mechanisms, the drives corresponding to each other among the plurality of unit drive mechanisms. The parts are arranged adjacent to each other.
The invention according to claim 3 is the drive device according to claim 1 or 2, wherein the connecting member in one unit driving mechanism and the connecting member in another unit driving mechanism include the movable portion. The movable portion is connected to the movable portion at positions facing each other, and the movable portion moves while maintaining a posture by driving of the drive portion.

According to a fourth aspect of the present invention, there is provided a connecting member configured by using a frame member disposed on the outer peripheral side of the movable part to which the driven body is fixed and an elastic body, and connecting the movable part and the frame member. And one or more unit drive mechanisms each having a drive unit coupled to the frame material, and an elastic member interposed between a fixed point and the frame material, The first unit driving mechanism having the first frame arranged along the outer periphery of the movable portion as the frame material, and the second frame arranged along the outer periphery of the first frame as the frame material. and a second unit driving mechanism, the connecting member of the first frame is connected to a first portion of said movable portion, said connecting member of said second frame is said in a path that avoids the first frame Second part of moving part Is connected, the the given driving displacement from the drive unit, the leverage of the frame member which has a fulcrum the binding site of the elastic member, the frame member and the connecting member while resisting the elastic deformation of the elastic member The coupling member of each unit driving mechanism is elastically deformed when the movable portion is driven in the same direction by the first and second unit driving mechanisms. Features.

According to a fifth aspect of the present invention, in the drive device according to the fourth aspect of the present invention, each drive unit included in the first and second unit drive mechanisms is a gap portion between the first frame and the second frame. It is characterized by being arranged in.
Also, the invention of claim 6 is the drive unit according to claim 4 or claim 5, and the connecting member in the first unit driving mechanism, and the connecting member in the second unit driving mechanism, the The movable portion is connected to the movable portion at a position opposed to each other via the movable portion, and the movable portion moves while maintaining the posture by driving of the drive portion.

According to a seventh aspect of the present invention, in the drive device according to any one of the first to sixth aspects, the elastic member undergoes elastic torsional deformation when a drive displacement is applied from the drive section. It is characterized by occurring.

According to an eighth aspect of the present invention, in the driving device according to any one of the first to seventh aspects, the connecting member is elastically deformed when a driving displacement is applied from the driving portion. It is characterized by occurring.

According to a ninth aspect of the present invention, in the driving apparatus according to any one of the first to eighth aspects, the driven body is an image sensor.

A tenth aspect of the invention is an image pickup unit comprising the driving device according to the ninth aspect of the invention and an optical system that forms an image on the image pickup device.

The invention of claim 11 is an image pickup apparatus, comprising the image pickup unit according to the invention of claim 10 .

According to the invention described in claims 1 to 11 , the drive displacement given from the drive section is expanded to the displacement of the driven body by the lever action of the frame material with the coupling portion with the elastic member as a fulcrum. Therefore, a large amount of movement can be ensured in the movable part to which the driven body is fixed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<1. First Embodiment>
<1-1. About Electrostatic Actuator>
FIG. 1 is a diagram showing a first situation of the configuration and operation of an actuator (electrostatic actuator) using electrostatic action. FIG. 1A is a top view of the electrostatic actuator, and FIG. 1B is a side view of the electrostatic actuator.

  FIG. 2 is a diagram showing a second situation of the configuration and operation of the electrostatic actuator. FIG. 2A is a top view of the electrostatic actuator. FIG. 2B is a side view of the electrostatic actuator, and FIG. 2C is a side view of the electrostatic actuator when a voltage is applied.

  In the present embodiment, an electrostatic actuator is employed in the drive unit of the drive device. As shown in FIG. 1 (a), the electrostatic actuator has a comb-shaped portion arranged alternately (alternately arranged). It is composed of one comb-tooth electrode 101 and a second comb-tooth electrode 102, and an electrostatic force generated by a voltage applied between the two comb-tooth electrodes is used as a drive source. Such an electrostatic actuator generates forces in different directions depending on the relative positions of the two comb electrodes. In the drawing, an XYZ rectangular coordinate system is written, but the X-axis direction corresponds to the direction in which each tooth of the first comb-tooth electrode 101 extends, and the Y-axis direction corresponds to the two comb-tooth electrodes 101 and 102. This corresponds to the direction along the interdental groove, and the Z-axis direction corresponds to the direction in which the teeth of the first comb electrode 101 are arranged.

  For example, as shown in FIG. 1B, a fixed first comb electrode (also referred to as “fixed comb portion”) 101 and a movable second comb electrode (also referred to as “movable comb portion”) 102. The movement of the movable comb portion 102 in a state where the comb tooth surfaces are arranged in the Y-axis direction without deviation will be described. In this state, when the switch SW is connected and a voltage is applied between the two comb electrodes, an attractive force in the X direction is generated between the fixed comb portion 101 and the moving comb portion 102. The moving comb portion 102 connected to the fixed portion 104 moves in the + X direction by this attractive force via the support member 103a formed of an elastic material extending in the X direction. When the switch SW is disconnected, the attractive force generated between the fixed comb portion 101 and the moving comb portion 102 disappears, and the moving comb portion 102 returns to the −X direction by the elastic force of the support member 103a. Thus, in a state where the mutual comb tooth surfaces are arranged without misalignment in the Y-axis direction, by controlling the voltage applied between the comb tooth electrodes, the movable comb portion 102 is moved in the X direction as indicated by the arrow HYa. Can be moved to.

  Next, the comb tooth surface is not in a state of being displaced in the Y-axis direction as shown in FIG. 1B, and the comb tooth surface of the moving comb portion 102 is the comb of the fixed comb portion 101 as shown in FIG. The movement of the moving comb portion 102 in a state where it is translated in the + Y direction with respect to the tooth surface (also referred to as “a state where the comb tooth surface is displaced”) will be described. However, unlike the support member 103a in FIG. 1, the support member 103b in FIG. 2 is linear in a top view. In this state, when the switch SW is connected and a voltage is applied between the two comb-tooth electrodes, an attractive force in the X direction and an attractive force in the Y direction are generated between the fixed comb portion 101 and the moving comb portion 102. As a result, the moving comb portion 102 connected to the fixed portion 104 via the rod-like support member 103b receives the force Fx in the + X direction and the force Fy in the −Y direction. The support member 103b is formed of a shape or material that has bending elasticity but does not have substantial elastic elasticity. Therefore, the moving comb portion 102 does not move in the −X direction, but moves in the substantially −Y direction while bending the support member 103b by receiving the force Fy in the −Y direction (see FIG. 2C). ). When the switch SW is cut, the attractive force generated between the fixed comb portion 101 and the moving comb portion 102 disappears, and the moving comb portion 102 returns to the substantially + Y direction by the bending elastic force of the support member 103b. In the state where the two comb tooth surfaces are arranged in the Y-axis direction without deviation in this manner, the comb tooth surface of the movable comb portion 102 is translated in the + Y direction with respect to the comb tooth surface of the fixed comb portion 101. By controlling the voltage applied between the electrodes, the moving comb portion 102 can be rotationally moved (turned) as indicated by an arrow HYb.

  Further, the force generated between the comb electrodes by the applied voltage increases in proportion to the number of comb teeth, and increases in proportion to the square of the applied voltage. On the other hand, the force generated between the comb-teeth electrodes is inversely proportional to the distance between the comb teeth, and decreases as the distance between the comb teeth increases. In addition, in order to prevent the short circuit by contact, each comb tooth is arrange | positioned in a mutually neutral position so that the distance between each comb-tooth electrode may become equal. Further, at the time of designing, a device such as giving rigidity to each comb tooth is applied.

<1-2. About Drive Device>
<1-2-1. Configuration>
Next, the drive device 1A according to the present embodiment will be described. FIG. 3 is a functional block diagram of the driving apparatus 1A according to the present embodiment. FIG. 4 is a top view of the driving apparatus 1A. FIG. 5 is a side view of the driving device 1A in an initial state before driving when viewed from the K1 direction in FIG.

  As shown in FIG. 3, the drive device 1 </ b> A includes a drive unit 5, a displacement transmission unit 6, and a movable unit 7.

  The drive unit 5 has a function of generating a displacement (also referred to as “drive displacement”) and applying the drive displacement to the displacement transmission unit 6. In the present embodiment, the above-described electrostatic actuator is employed in the drive unit 5 and a drive displacement is generated by applying a voltage between the comb electrodes. In the electrostatic actuator used for the drive unit 5, the comb tooth surface of the moving comb portion and the comb tooth surface of the fixed comb portion are arranged so as to be shifted from each other.

  The displacement transmission unit 6 includes a displacement magnifying mechanism 8, and has a function of generating an output displacement obtained by enlarging (enlarging) the drive displacement given from the drive unit 5 and transmitting the output displacement to the movable unit 7. Yes.

  The movable part 7 is moved in a predetermined direction according to the output displacement.

  Here, a specific configuration of the driving device 1A including the above functional units will be described.

  As shown in FIG. 4, the driving apparatus 1 </ b> A has a substantially rectangular frame structure FR that is spaced from the movable portion 7 along the outer periphery of the movable portion 7 that fixes the driven body. The frame structure FR is divided in half. The first frame 11 corresponding to one of them (the upper half in the figure) and the second frame corresponding to the other one (the lower half in the figure). The frame 21 is disposed symmetrically with respect to the symmetry line CC of the movable portion 7. The drive device 1A also includes four electrostatic actuators 10a, 10b, 10c, and 10d as the drive unit 5 for driving the movable unit 7 via the frame structure FR. Each of the electrostatic actuators 10a to 10d includes fixed comb portions 101a, 101b, 101c, and 101d, and movable comb portions 102a, 102b, 102c, and 102d that face the fixed comb portions 101a to 101d, respectively, and between the comb electrodes. A drive displacement is generated in accordance with the voltage applied to.

  Although the frame structure FR is an element of the displacement transmission unit 6 in FIG. 3, the structure and function of the first frame 11 will be described in detail below. The second frame 21 also has the same structure and function as the first frame 11.

  The first frame 11 is formed by a lateral side portion 11L and a pair of longitudinal side portions 11H that are continuous on both sides of the lateral side, and one end of the first support member 13a and the second side are fixed respectively. The support member 13b supports a portion closer to the symmetric line CC than the midpoint of each of the pair of vertical sides 11H. The first support member 13a and the second support member 13b are made of a material having torsional elasticity (for example, metal). More specifically, these support members 13a and 13b may be integrally formed with the first frame 11, but by being designed to be thinner (or thinner) than the first frame 11, It is formed as an elastic member that is more elastically torsionally deformed than the first frame 11.

  In addition, electrostatic actuators 10 a and 10 b are connected to both ends of the first frame 11, and driving displacement from the electrostatic actuators 10 a and 10 b is applied to the first frame 11. Since the interdental groove of each comb electrode of each electrostatic actuator 10a, 10b extends along the Y direction in FIG. 4, each electrostatic actuator 10a, 10b is based on the same principle as in FIG. Can drive the vertical side 11H in the Y direction.

  In the first frame 11, the first long portion 12 a extending from the connection end PFa of the electrostatic actuator 10 a through the support point (also referred to as “coupling portion”) BPa by the first support member 13 a is the first This corresponds to one of the vertical side portions 11H of one frame 11, and is an element of the displacement enlarging mechanism 8 (FIG. 3) of the first frame 11. Specifically, as shown in FIG. 5, the first long portion 12a is configured to be tiltable in the XY plane with the support point BPa as a fulcrum, and the support point BPa is the first long length. It is provided between the midpoint of the part 12a and one end PFa of the first long part 12a. For this reason, the first elongate portion 12a uses a so-called lever principle to change the drive displacement applied to one end (connection end PFa) of the first elongate portion 12a in addition to the first elongate portion 12a. It becomes possible to enlarge and output at the end PEa. Details will be described later.

  In the first frame 11, the second elongated portion 12b extending from the connection end PFb of the electrostatic actuator 10b through the support point (coupling part) BPb by the second support member 13b is also the first frame 11. It corresponds to another one of the vertical side portions 11H of the frame 11 and is an element of the displacement magnifying mechanism 8 (FIG. 3) of the first frame 11 like the first frame 11.

  Further, the approximate center of the lateral side portion 11 </ b> L of the first frame 11 is connected to the movable portion 7 by the first connecting member 14. The first connecting member 14 is formed of a material having bending elasticity (for example, metal). Specifically, a part of the members integrally formed with the first frame 11 is compared with the first frame 11. The first connecting member 14 can be obtained by designing it to be thin (or thin), and even if it is made of the same material as the first frame 11, the first size can be selected by such relative size selection. Compared with the frame 11, it is easily elastically deformed.

  The second frame 21 has the same configuration as the first frame 11 described above, and is an element of the displacement magnifying mechanism 8. In brief, the second frame 21 is supported by a third support member 13c and a fourth support member 13d. Electrostatic actuators 10c and 10d are connected to both ends of the second frame 21, respectively. The second frame 21 has a third elongated portion 12c and a fourth elongated portion 12d, each having a support point (bonding site) BPc and a support point (bonding site) BPd as fulcrums. Yes. These long portions 12c and 12d are elements of the displacement enlarging mechanism 8 that can tilt in the XY plane.

  Further, the second frame 21 has a second connecting member 15. The second connecting member 15 is designed to be thinner (or thinner) than the second frame 21 and is more easily elastically deformed than other parts of the second frame 21. And the said 1st connection member 14 and the said 2nd connection member 15 are comprised so that the movable part 7 may be hold | maintained in the position (symmetric position) which mutually opposes.

  As described above, the upper half and the lower half with the symmetry line C-C of the movable portion 7 as a boundary have a symmetric configuration, and each is a unit drive mechanism. In this embodiment, the two unit drive mechanisms are symmetrically arranged with respect to the movable part 7, but the function itself for moving the movable part 7 has each one unit drive mechanism. In the drive device 1A, among the four electrostatic actuators 10a to 10d, the electrostatic actuators corresponding to each other between the two unit drive mechanisms are arranged adjacent to each other (for details, refer to FIG. 4). Electrostatic actuator 10a and electrostatic actuator 10c, and electrostatic actuator 10b and electrostatic actuator 10d). According to this, space saving of the drive part 5 is attained.

<1-2-2. Operation>
Next, the operation of the driving apparatus 1A having the above-described configuration will be described. FIG. 6 is a side view of the driving device 1A in a driving state when viewed from the K1 direction in FIG. FIG. 7 is a diagram illustrating an initial state and a driving state of the driving apparatus 1A.

  In the initial state before driving shown in FIG. 5, when the force Fay in the −Y direction from the electrostatic actuator 10a is applied to the one end PFa side of the first elongated portion 12a, the first elongated portion 12a is The first support member 13a that can be elastically deformed is rotated (rotated) in the XY plane around the support point BPa against the elastic force of the support member 13a while generating a twist. In short, one end PFa of the first elongate portion 12a is displaced in the −Y direction, and the other end PEa of the first elongate portion 12a is displaced in the + Y direction.

  At this time, the drive displacement given to the one end PFa side of the first long portion 12a by the electrostatic actuator 10a is expanded (increased) by the displacement expansion mechanism 8 using the principle of the lever, and the first long portion It is output to the other end PEa side of the part 12a. That is, the displacement (output displacement) output to the other end PEa side of the first long portion 12a is larger than the drive displacement.

  Similarly, when a force Fcy in the −Y direction from the electrostatic actuator 10c is applied to the one end PFc side of the third long portion 12c, the third long portion 12c is elastically deformed to the third support. The member 13c rotates about the support point BPc while generating a twist. In short, one end PFc of the third long portion 12c is displaced in the −Y direction, and the other end PEc of the third long portion 12c is displaced in the + Y direction. As a result, a displacement that is larger than the drive displacement applied to one end PFc of the third long portion 12c is output from the other end PEc side of the third long portion 12c.

  In addition, the second elongate portion 12b and the third elongate portion 12d (not shown in FIG. 5) are also tilted by receiving the force from the electrostatic actuators 10b and 10d, respectively, and the elongate portions 12b and 12d. From the other ends PEb and PEd, displacements larger than the drive displacement given to the one ends PEb and PEd of the long portions 12b and 12d are output.

  And the output displacement which arose in each other end PEa of the two elongate parts 12a and 12b in the 1st flame | frame 11 is transmitted to the movable part 7 via the 1st connection member 14, and 2nd The output displacement generated on the other end PEc, PEd side of the two long portions 12c, 12d in the frame 21 is transmitted to the movable portion 7 via the second connecting member 15. As the output displacement increases, the movable portion 7 moves in the + Y direction as shown in FIG.

  At this time, the first connecting member 14 and the second connecting member 15 hold the movable portion 7 while being elastically deformed as the movable portion 7 moves in the + Y direction. As a result, the smooth operation of the driving device 1A becomes possible.

  Specifically, as described above, each of the long portions 12a to 12d performs rotational movement around the support points BPa to BPd when driven. For this reason, the output displacement generated at the other ends PEa to PEd of the long portions 12a to 12d includes the displacement QX in the X direction and the displacement QY in the Y direction.

  For example, in the driving state shown in FIG. 7, the output displacement (first output displacement) generated by the first long portion 12a and the second long portion 12b is represented by an arrow AR1. The first output displacement can be represented by a displacement QX1 in the −X direction and a displacement QY1 in the + Y direction. Further, in the driving state shown in FIG. 7, the output displacement (second output displacement) generated by the third long portion 12c and the fourth long portion 12d is represented by an arrow AR2. The second output displacement can be represented by a displacement XX2 in the + X direction and a displacement QY2 in the -Y direction.

  As described above, the first output displacement in the first frame 11 and the second output displacement in the second frame 21 have the displacement QX1 in the −X direction and the displacement QX2 in the + X direction, respectively. . Therefore, in the driving state of FIG. 7, the distance between the other end PEa of the first long portion 12a and the other end PEc of the third long portion 12c is compared with the distance in the initial state of FIG. And shortened. Therefore, in the driving apparatus 1A using the displacement magnifying mechanism 8 as described above, the first connecting member 14 and the second connecting member 15 are designed to be more easily elastically deformed than the frame, and 2 during operation. By elastically deforming the two connecting members (in this case, bending deformation is generated), the displacement in the X direction caused by driving is absorbed, and the operation of the two unit driving mechanisms in the driving device 1A in parallel is facilitated. ing.

  Further, as described above, in the driving device 1A, the first connecting member 14 and the second connecting member 15 hold the movable portion 7 at a position facing each other. According to this, the −X direction force F14 applied from the first connecting member 14 to the movable portion 7 and the + X direction force F15 applied from the second connecting member 15 to the movable portion 7 are mutually on the same straight line. It becomes possible to add to the movable part 7 from the facing direction. Therefore, the posture of the movable portion 7 is maintained without disturbing the balance of the movable portion 7 by the force F14 from the first connecting member 14 and the force F15 from the second connecting member 15 in operation. The movable part 7 can be moved in the Y direction parallel to the X axis (while maintaining).

  As described above, the movable portion 7 that moves in the + Y direction as the output displacement increases is the force from the electrostatic actuators 10a, 10b, 10c, and 10d and the long portions 12a, 12b, 12c, and 12d. The support members 13a, 13b, 13c, and 13d generated by the tilting are stopped at a position where the restoring force of the twist is balanced. For example, when the application of the voltage between the comb electrodes is stopped, the movable portion 7 returns to the original position by the restoring force of each of the support members 13a to 13d that has been twisted. Therefore, in the present embodiment, the force generated in the electrostatic actuators 10a to 10d increases in proportion to the square of the voltage applied between the comb electrodes, so that the driving device 1A controls the applied voltage. Thus, the displacement (movement amount) of the movable portion 7 can be adjusted.

  As described above, the driving device 1A can expand the driving displacement from the electrostatic actuators 10a, 10b, 10c, and 10d and move the movable portion 7 in the Y direction in parallel with the X axis. According to this, even when the drive displacement of the drive unit 5 is small, it is possible to ensure a sufficient amount of movement in the movable unit 7. In addition, when an electrostatic actuator is used as the drive unit 5, it is not necessary to secure a specific space for the drive unit 5 as compared with the case where a stepping motor or the like is used for the drive unit 5. It becomes possible to reduce the size.

  In this embodiment, when the direction connecting the connecting members 14 and 15 is the vertical direction, a plurality of unit driving mechanisms are arranged vertically symmetrically, and each unit driving mechanism is further connected to the connecting members 14 and 15 and the frames 11 and 12. By making the structure symmetrical with respect to the coupling point, the movable part 7 can be moved without changing the posture of the movable part 7 by applying the same voltage to the electrostatic actuators 10a, 10b, 10c, and 10d. it can.

<2. Application example>
Next, an application example of the drive device 1A of the above embodiment will be described.

  As an example of such application, there is an imaging unit that employs the driving device 1A as an AF mechanism, and there is a folding mobile phone as a kind of imaging device provided with the imaging unit. FIG. 8 is a diagram illustrating the imaging unit 30. FIG. 9 is a diagram showing a foldable mobile phone 70 including the imaging unit 30.

  As shown in FIG. 8, the imaging unit 30 includes a package (box body: housing) 35 and a protective glass 36, and the imaging element 31 is in a sealed space formed by the package 35 and the protective glass 36. And a zoom lens 32 as an optical system for forming a subject image thereon.

  The image pickup device (for example, CCD) 31 is configured as an area sensor in which primary color transmission filters of R (red), G (green), and B (blue) are arranged in a checkered pattern (Bayer array) in pixel units. It functions as an imaging means for acquiring such an image signal (image). Further, the image pickup device 31 is disposed (installed) on the movable portion 7 of the driving device 1A installed on the fixed portion 33 in the sealed space, and as indicated by the double arrow HW by the movement of the movable portion 7 of the driving device 1A, Move in the direction of the optical axis L.

  The zoom lens 32 is supported between the protective glass 36 and the image sensor 31 in the sealed space.

  In the imaging unit 30 having such a configuration, the focus adjustment is performed by moving the imaging element 15 in the direction of the optical axis L by controlling the voltage applied between the comb electrodes.

  In order to prevent dust from entering the space formed by the package 35 and the protective glass 36, the imaging unit 30 is assembled in a clean room (or clean bench), for example. Furthermore, the imaging unit 30 forms a sealed space, thereby preventing dust from entering the electrostatic actuator used in the drive unit 5 of the drive device 1A and protecting the electrostatic actuator. Moreover, in the imaging unit 30, since the air convection is eliminated by forming the sealed space, variation in the load on the driving device 1A can be reduced.

  The imaging unit 30 is mounted as a micro camera unit (MCU) in a small electronic device (imaging device) such as the mobile phone 70 shown in FIG. The cellular phone 70 includes a camera lens unit 71, an external display unit 72, and a photographing light 73. The imaging unit 30 is built in the mobile phone 70 so that a subject image guided from the camera lens unit 71 can be acquired.

  As described above, the drive device 1A that can be miniaturized is employed as a drive device that drives components in the MCU, for example, and enables further miniaturization of the MCU.

<3. Second Embodiment>
FIG. 10 is a top view of a driving apparatus 1B according to the second embodiment of the present invention. FIG. 11 is a side view of the driving device 1B in a driving state when viewed from the K2 direction in FIG. Hereinafter, the driving device 1B will be described focusing on differences from the driving device 1A.

  Similarly to the driving device 1A, the driving device 1B according to the second embodiment includes a driving unit 5 including four electrostatic actuators 50a, 50b, 50c, and 50d, a displacement transmitting unit 6 having a displacement enlarging mechanism 8, and a movable unit 7. (FIG. 3). As shown in FIG. 10, the driving device 1 </ b> B is different from the driving device 1 </ b> A in that the displacement transmitting unit 6 includes a substantially rectangular first frame 51 and a second frame 52 having different sizes. It is a heavy frame FR2. Further, when viewed from the top, each electrostatic actuator 50a to 50d is placed between the first frame 51 and the second frame 61 so as to be accommodated in the larger frame (here, the first frame 51). Are arranged substantially concentrically. The electrostatic actuators 50 a, 50 b, 50 c, 50 d are arranged in the gap between these two frames 51, 52, whereby the respective comb electrodes are present inside the first frame 51. According to the configuration of the driving device 1B in which the comb electrode does not protrude from the frame, a compact configuration can be maintained even when the number of comb teeth is increased.

  The operation of the driving device 1B is the same as that of the driving device 1A. Briefly, first, a pair of vertical side portions 51H (first long portion 52a and second long portion 52b) in which the drive displacement generated by the electrostatic actuators 50a and 50b is included in the first frame 51. Given to one end of each. The output displacement enlarged by the displacement magnifying mechanism 8 is output to the other ends of the first elongate portion 52a and the second elongate portion 52b. Similarly, each of the pair of vertical side portions 52H (the third long portion 52c and the second long portion 52d) in which the drive displacement generated by the electrostatic actuators 50c and 50d is included in the second frame 52. Given at one end. Then, the output displacement expanded by the displacement enlarging mechanism 8 is output to the other ends of the third elongate portion 52c and the fourth elongate portion 52d.

  Thus, the output displacement output to the other ends of the two long portions 52a and 52b in the first frame 51 is applied to the lower side of FIG. 10 in the horizontal side portion 51L of the first frame 51. The output displacement transmitted to the movable part 7 via the corresponding relay part 51T and the first connecting member 54 subsequent thereto is outputted to the other ends of the two long parts 52c and 52d in the second frame 52. The second frame 52 is transmitted to the movable portion 7 via the relay portion 52T corresponding to the upper side of FIG. The movable portion 7 moves in the + Y direction as shown in FIG. 11 as the output displacement increases.

  In the second embodiment, a unit drive mechanism having a first frame 51 (hereinafter “outer unit drive mechanism”) and a unit drive mechanism having a second frame 52 (hereinafter “inner unit drive mechanism”) are provided. By adjusting the amplification factor of the insulator with respect to the stroke of each of the electrostatic actuators 50a to 50d so as to give the same displacement to the movable part 7, the posture of the movable part 7 before and after the movement can be made unchanged. In addition, by adjusting in advance the voltage applied to each of the electrostatic actuators 50a to 50d so that the outer unit driving mechanism and the inner unit driving mechanism respectively give the same displacement to the movable part 7, before and after the movement of the movable part 7 In this case, the posture of the movable part 7 can be made unchanged.

  The movable portion 7 that moves in the + Y direction as the output displacement increases corresponds to the support members that are generated by the force from the electrostatic actuators 50a to 50d and the tilting of the long portions 52a, 52b, 52c, and 52d. It stops at a position where the restoring force of torsion of 53a, 53b, 53c, 53d is balanced.

  In these operations, since the first connecting member 54 extends toward the movable portion 7 in a path passing through the missing portion formed on the lower lateral side portion 52L of the second frame 52, the first connecting member 54 and There is no interference with the second frame 52.

  A method of incorporating the driving device 1B of the second embodiment into the imaging unit and further mounting it on the imaging device is the same as in the first embodiment.

<4. Modification>
In this invention, it is good also as a structure further equipped with the position sensor which measures the position of the image pick-up element 31 in the image pick-up unit 30 in the said application example. FIG. 12 is a diagram illustrating an imaging unit 30 including a position sensor.

  Specifically, as shown in FIG. 12, a position sensor PSe for measuring the position of the movable part 7 is arranged in the sealed space of the imaging unit 30, and the position (measurement position) of the movable part 7 from the position sensor PSe. To get. Then, the current position of the movable part 7 is corrected by comparing the position information with the position (converted position) of the movable part 7 obtained by conversion from the applied voltage. Specifically, when the measurement position and the conversion position are different, feedback control is performed to correct the current position of the movable unit 7 by correcting the applied voltage so that the measurement position matches the conversion position. .

  According to this, it is possible to perform appropriate focus adjustment even in a situation where the operation accuracy of the drive device 1A deteriorates. In addition, as position sensor PSe, the sensor which measures the distance to a ranging object using the reflected light of the laser irradiated to the ranging object, for example can be employ | adopted.

  In each of the above embodiments, the supporting members 13a, 13b, 13c, 13d and the connecting members 14, 15 in the driving device 1A are formed integrally with the frame, but are designed to be thinner than the frame, thereby being elastic. Although it was easy to deform | transform, it is not limited to this. Specifically, the support members 13a, 13b, 13c, 13d and the connection members 14, 15 are configured using a material that is more easily elastically deformed than members used in the frame, and the support members 13a to 13d and The connecting members 14 and 15 may be easily elastically deformed.

It is a figure which shows the structure and operation | movement of an electrostatic actuator. It is a figure which shows the structure and operation | movement of an electrostatic actuator. It is a functional block diagram of the drive device concerning a 1st embodiment. It is a top view of a drive device. It is a side view of the drive device in the initial state before driving. It is a side view of the drive device in a drive state. It is a figure which shows the initial state and drive state of a drive device. It is a figure which shows an imaging unit. It is a figure which shows a foldable mobile phone provided with an imaging unit. It is a top view of the drive device concerning a 2nd embodiment. It is a side view of the drive device concerning the modification in a drive state. It is a figure which shows an imaging unit provided with a position sensor.

Explanation of symbols

1A, 1B Driving device 10a, 10b, 10c, 10d Electrostatic actuator 11 First frame 21 Second frame 12a, 12b, 12c, 12d Long portion 13a, 13b, 13c, 13d Support member 14 First connecting member 15 Second connecting member

Claims (11)

A frame material arranged on the outer peripheral side of the movable part to which the driven body is fixed;
A connecting member configured using an elastic body and connecting the movable part and the frame material;
Driving parts respectively coupled to the frame material;
An elastic member interposed between a fixing point and the frame material;
A plurality of unit drive mechanisms comprising
The drive displacement given from the drive unit is caused by the lever action of the frame material with the coupling portion with the elastic member as a fulcrum while resisting elastic deformation of the elastic member through the frame material and the connecting member. Expanded to the displacement of the driven body ,
When the movable part is driven in the same direction by a plurality of the unit drive mechanisms, the connecting member of each unit drive mechanism is elastically deformed .   The drive device according to claim 1,
  Among the drive units included in each of the plurality of unit drive mechanisms, drive units corresponding to each other among the plurality of unit drive mechanisms are arranged adjacent to each other.   The drive device according to claim 1 or 2,
  The connecting member in one unit driving mechanism and the connecting member in the other unit driving mechanism are connected to the movable part at positions facing each other via the movable part,
  The drive unit according to claim 1, wherein the movable unit moves while maintaining a posture by driving the drive unit.   A frame material arranged on the outer peripheral side of the movable part to which the driven body is fixed;
  A connecting member configured using an elastic body and connecting the movable part and the frame material;
  Driving parts respectively coupled to the frame material;
  An elastic member interposed between a fixing point and the frame material;
Including one or more unit driving mechanisms having
  As the unit drive mechanism,
  A first unit driving mechanism having, as the frame material, a first frame arranged along an outer periphery of the movable portion;
  A second unit drive mechanism having a second frame arranged along the outer periphery of the first frame as the frame material;
Have
  The connecting member of the first frame is connected to a first part of the movable part;
  The connecting member of the second frame is connected to the second part of the movable part through a path avoiding the first frame,
  The drive displacement given from the drive unit is caused by the lever action of the frame material with the coupling portion with the elastic member as a fulcrum while resisting elastic deformation of the elastic member through the frame material and the connecting member. Expanded to the displacement of the driven body,
  The driving device according to claim 1, wherein when the movable unit is driven in the same direction by the first and second unit driving mechanisms, the connecting member of each unit driving mechanism is elastically deformed.   The drive device according to claim 4, wherein
  Each drive unit included in the first and second unit drive mechanisms is disposed in a gap portion between the first frame and the second frame.   The drive device according to claim 4 or 5,
  The connecting member in the first unit driving mechanism and the connecting member in the second unit driving mechanism are connected to the movable part at positions facing each other via the movable part,
  The drive unit according to claim 1, wherein the movable unit moves while maintaining a posture by driving the drive unit.   The drive device according to any one of claims 1 to 6,
  The driving device according to claim 1, wherein the elastic member generates elastic torsional deformation when a driving displacement is applied from the driving unit.   The drive device according to any one of claims 1 to 7,
  The driving device according to claim 1, wherein the connecting member is elastically deformed when a driving displacement is applied from the driving unit.   The drive device according to any one of claims 1 to 8,
  A driving apparatus, wherein the driven body is an image sensor.   An imaging unit comprising: the driving device according to claim 9; and an optical system that forms an image on the imaging element.   An imaging device comprising the imaging unit according to claim 10.

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