JP2009044861A - Driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To a provide a driving device wherein the number of electrode lands is reduced and thus size reduction can be achieved. <P>SOLUTION: The driving device includes: a piezoelectric body 101-1 in which first bending displacement is excited by electrical control along first and second bending directions orthogonal to the direction of driving of a lens tube 101-5 and a piezoelectric body 101-2 in which second bending displacement is excited; an elastic member 101-4 that oscillates along the driving direction based on the first and second bending displacements and drives the lens tube 101-5; and a frictional member 101-3. The piezoelectric bodies 101-1, 101-2 respectively include: piezoelectric elements 101-1B, 101-2B; sheet electrodes 101-1D, 101-2D that are provided on one faces of the piezoelectric elements 101-1B, 101-2B and to which driving voltage is applied; and shim members 101-1E, 101-2E that are provided on the other faces of the piezoelectric elements 101-1B, 101-2B and to which common voltage is applied. The shim member 101-1E and the shim member 101-2E are electrically coupled together. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a drive device that drives a driven body using an electromechanical transducer. More specifically, the present invention relates to a driving device used for driving a lens in an optical device such as a photographing lens of a camera.

  A driving device using a conventional electromechanical transducer is described below with reference to FIGS.

  That is, FIG. 18 shows a cross-sectional view of a driving device using a conventional electromechanical transducer. According to Patent Documents 1 and 2, a driving device using a conventional electromechanical transducer includes a piezoelectric body 301 that is an electromechanical transducer. The piezoelectric body 301 has a structure that expands and contracts by electrical control. The rod-shaped drive member 302 is connected to the piezoelectric body 301, and the expansion / contraction direction of the piezoelectric body 301 and the drive direction of the drive member 302 are the same. The lens barrel 304 that is a driven body is connected to the driving member 302 by friction engagement.

  A lens 3011, which is an optical component, is fitted inside the lens barrel 304, and the thickness direction (optical axis direction) of the lens 3011 and the drive direction of the drive member 302 are the same. Light representing an object to be imaged input from the outside via the lens 3011 is taken into an image sensor 3012 such as a CCD. The image sensor 3012 is mounted on a circuit board 3013, and the image sensor 3012 and the circuit board 3013 are fixed to each other by soldering or the like. The circuit board 3013 is fixed on the camera module housing 306.

  The operation of the drive device using the electromechanical transducer element configured as described above will be described. The piezoelectric body 301 is attached so as to expand and contract in the longitudinal direction of the driving member 302, that is, in the thickness direction (optical axis direction) of the lens 3011 by electrical control. The expansion / contraction movement of the piezoelectric body 301 is transmitted to the driving member 302, and the movement becomes the driving force of the driving member 302. The lens barrel 304, which is a driven body, and the driving member 302 are connected by frictional engagement, and the lens barrel 304 moves up and down in the optical axis direction in accordance with the driving of the driving member 302. Therefore, the lens 3011 incorporated in the lens barrel 304 also exhibits a movement that matches the driving of the driving member 302. As described above, the position adjustment (focus adjustment) of the lens 3011 is performed through the expansion and contraction of the piezoelectric body 301.

  Light representing an object to be imaged captured from the outside via the lens 3011 is captured by an image sensor 3012 such as a CCD, converted into an electric signal, and then transmitted to a circuit board 3013 disposed below the image sensor 3012. Information processing according to the application is performed.

  A piezoelectric actuator, which is a driving device using a conventional electromechanical transducer, will be described with reference to FIG.

  FIG. 19 is a schematic diagram of a piezoelectric actuator using a conventional electromechanical transducer. According to Patent Document 3, the conductive thin plate 31-2 has a bent shape having two apexes extending from the apex 31-1, with the apex 31-1 as the apex. The inclined portion is fixed to the substrate on which the inclined portion extends and contacts.

  Unimorph type piezoelectric elements 31-3A and 31-3B are attached to the inclined portion on the upper side of the inclined portion along the inclination. The piezoelectric elements 31-3A and 31-3B are pressure-bonded to the thin plate 31-2, and the thin plate 31-2 serves as a common electrode (second electrode) for the piezoelectric elements 31-3A and 31-3B. The first electrodes are respectively crimped to the other main surfaces of the piezoelectric elements 31-3A and 31-3B. Electrodes are bonded to the first electrodes of the piezoelectric elements 31-3A and 31-3B and the thin plate 31-2.

  The operation of the piezoelectric actuator, which is a drive device using the electromechanical transducer element configured as described above, will be described.

  The piezoelectric elements 31-3A and 31-3B are polarized so that when a positive drive voltage is applied to the first electrode with respect to the second electrode (common electrode), the piezoelectric element contracts in the length direction. Further, when a negative drive voltage is applied to the first electrode with respect to the second electrode (common electrode), the piezoelectric element is polarized so as to extend in the length direction. Therefore, when a positive drive voltage is applied to the first electrode with respect to the second electrode (common electrode), the piezoelectric elements 31-3A and 31-3B shrink in a direction parallel to the inclined portion. Conversely, when a negative drive voltage is applied to the first electrode with respect to the second electrode (common electrode), the piezoelectric elements 31-3A and 31-3B extend in a direction parallel to the inclined portion. However, since the thin plate 31-2 does not expand and contract, the lengths of the piezoelectric elements 31-3A and 31-3B and the inclined portion of the thin plate 31-2 change relatively. As a result, for example, when the piezoelectric element 31-3A is reduced in the length direction, the central portion of the inclined portion of the thin plate 31-2 is recessed downward and perpendicular to the slope, and both end portions of the inclined portion are perpendicular to the slope. Warps upward. On the contrary, when the piezoelectric element 31-3A extends in the length direction, the central portion of the inclined portion of the thin plate 31-2 warps vertically upward with respect to the inclined surface, and both end portions of the inclined portion are perpendicular to the inclined surface. A downward force is applied.

  By electrically controlling the piezoelectric elements 31-3A and 31-3B that perform such expansion and contraction, the top portion 31-1 can be controlled to move in a predetermined direction. Thereby, the to-be-conveyed object (FIG. 19 broken line part) which contact | connects the top part 31-1 can be conveyed according to a motion of the top part 31-1. As described above, the piezoelectric actuator is a driving device that conveys the object to be conveyed using the expansion and contraction motion of the piezoelectric element.

  An example in which a voltage is applied to the piezoelectric actuator described in FIG. 19 will be described with reference to FIGS. 20 to 22, the same components as those described above with reference to FIG. 19 are denoted by the same reference numerals. Therefore, description of these components is omitted. Furthermore, the configuration of FIG. 22 is a hypothetical configuration conceived from the invention described in Patent Document 3, and is not a known configuration described in Patent Document 3. Therefore, the problem of the present invention according to FIG. It should be noted that the inventor has derived this.

  20 and 21, the first electrodes of the piezoelectric elements 31-3A and 31-3B are electrically connected to the drive circuit 33 via switches 33A and 33B, respectively. Then, the drive voltage is applied to the piezoelectric elements 31-3A and 31-3B when the drive circuit 33 supplies a drive pulse signal or a drive pulse signal having a high frequency. The second electrodes (common electrodes) of the piezoelectric elements 31-3A and 31-3B are always held at the ground potential. Therefore, the first electrodes of the piezoelectric elements 31-3A and 31-3B are connected to the drive circuit 33 so that a positive voltage is applied to the second electrodes (common electrodes) of the piezoelectric elements 31-3A and 31-3B. It is connected. In FIG. 22, the first electrode of the piezoelectric element 31-3A is one of the drive circuits 33 so that the first electrode of the piezoelectric element 31-3A has a positive voltage with respect to the first electrode of the piezoelectric element 31-3B. The first electrode of the piezoelectric element 31-3B is connected to the terminal on the other side of the drive circuit 33. Furthermore, the intermediate potential is electrically connected so as to be applied to the thin plate 31-2 which is the second electrode (common electrode) of the piezoelectric elements 31-3A and 31-3B.

  20 to 22, “+” indicates a state in which a drive voltage is applied, and “GND” indicates a state in which the drive voltage is held at a ground potential (a state in which no drive voltage is applied).

  The operation of the piezoelectric actuator, which is a drive device using the electromechanical transducer element configured as described above, will be described.

  The following description will be made with reference to FIG. In the example shown in FIG. 20, the switch 33A is closed and the switch 33B is open. Accordingly, in the piezoelectric element 31-3A, a positive voltage is applied to the first electrode with respect to the second electrode (common electrode). For this reason, as described above, the piezoelectric element 31-3A is reduced in the length direction, and the central portion of the inclined portion of the thin plate 31-2 on the side to which the piezoelectric element 31-3A is fixed is recessed vertically downward with respect to the inclined surface. The both end portions of the inclined portion warp vertically upward with respect to the inclined surface. On the other hand, the first electrode of the piezoelectric element 31-3B is not electrically connected, and therefore the piezoelectric element 31-3B does not expand or contract. As a result, the top portion 31-1 moves to the left in FIG. 20 in conjunction with the movement of the inclined portion of the thin plate 31-2 on the side to which the piezoelectric element 31-3 A is fixed. Along with the movement of the top portion 31-1, the transported object in contact with the top portion 31-1 is transported to the left side of FIG.

  The following description will be made with reference to FIG. In the example shown in FIG. 21, both switches 33A and 33B are closed. Accordingly, in the piezoelectric elements 31-3A and 31-3B, a positive voltage is applied to the first electrode with respect to the second electrode (common electrode). For this reason, as described above, the piezoelectric elements 31-3A and 31-3B are both reduced in the length direction. Therefore, the central portion of the inclined portion of the thin plate 31-2 is recessed vertically downward with respect to the slope, and both end portions of the inclined portion warp vertically upward with respect to the slope. As a result, an equal force is applied to the top portion 31-1 from both inclined portions so as to cancel each other's forces. Therefore, the top portion 31-1 remains substantially in the original position in the horizontal direction.

  The description will be made with reference to FIG. In the example shown in FIG. 22, the first electrode of the piezoelectric element 31-3A is applied with a positive voltage with respect to the first electrode of the piezoelectric element 31-3B, and the piezoelectric elements 31-3A and 31-3B The intermediate potential is applied to the thin plate 31-2 which is the second electrode (common electrode) of the piezoelectric elements 31-3A and 31-3B. Both switches 33A and 33B are closed.

  Therefore, in the piezoelectric element 31-3A, a positive voltage is applied to the first electrode with respect to the second electrode (common electrode), and the piezoelectric element 31-3A shrinks in the length direction. Thereby, the central portion of the inclined portion of the thin plate 31-2 on the side to which the piezoelectric element 31-3A is fixed is recessed vertically downward with respect to the inclined surface, and both end portions of the inclined portion warp vertically upward with respect to the inclined surface. On the other hand, in the piezoelectric element 31-3B, a negative voltage is applied to the first electrode with respect to the second electrode (common electrode), and the piezoelectric element 31-3B extends in the length direction. Accordingly, the central portion of the inclined portion of the thin plate 31-2 on the side to which the piezoelectric element 31-3B is fixed rises vertically upward with respect to the inclined surface, and both ends of the inclined portion are applied with a downward force perpendicular to the inclined surface. .

  As a result, the top portion 31-1 moves in conjunction with the movement of the respective inclined portions that fix the piezoelectric elements 31-3A and 31-3B, but the moving direction is the left side of FIG. Due to the movement of the top portion 31-1, the object to be conveyed in contact with the top portion 31-1 is transported to the left side in FIG.

Patent Document 4 proposes a piezoelectric actuator in which a mirror or the like connected to a plurality of piezoelectric bodies is inclined in a desired direction. For example, there has been proposed a piezoelectric actuator in which another unimorph or bimorph piezoelectric body is attached via an actuated member on the other end face of the unimorph or bimorph piezoelectric body to which one end is fixed.
Japanese Patent Laid-Open No. 4-69070 (published March 4, 1992) JP 7-298656 A (published on November 10, 1995) JP 2006-121066 A (published May 11, 2006) JP 2003-209981 A (published July 25, 2003)

  In the driving apparatus using the conventional electromechanical transducer shown in FIG. 18, the expansion / contraction direction of the piezoelectric body 301 and the driving direction of the driving member 302 are coincident with each other. The position of the lens 3011 can be adjusted smoothly. However, in the above-described conventional configuration, since the expansion / contraction direction of the piezoelectric body 301 and the driving direction of the driving member 302 are the same, there is a problem that a space required for the driving operation increases and the size of the driving device itself increases. .

  In the piezoelectric actuator using the conventional electromechanical exchange element shown in FIGS. 20 to 22, the thin plate 31-2 is used as the second electrode (common electrode) of the piezoelectric elements 31-3A and 31-3B. The number of electrodes (electrode lands) that can be soldered was reduced. However, in the above conventional configuration, for example, as shown in FIG. 21, when the same drive voltage is simultaneously applied to the piezoelectric elements 31-3A and 31-3B to the thin plate 31-2 which is a common electrode, the piezoelectric element 31- Since the polarization directions of 3A and 31-3B are set vertically upward with respect to the arrows α and β and the inclined portion, the expansion and contraction directions of the piezoelectric elements 31-3A and 31-3B are both reduced in a direction parallel to the inclination. To do. As a result, both of the two inclined portions have a problem that the center portion is depressed and both end sides warp, and it is difficult to move the top portion 31-1 in a predetermined direction. In order to bend one of the thin plate inclined portions, for example, as shown in FIG. 20, the switch 33A connected to the power supply 32 is closed and the switch 33B is opened so that the piezoelectric element 31-3B is not bent. There was a need to adjust. However, in this case, there is a problem that the driving force of the piezoelectric actuator is reduced.

  Alternatively, as shown in FIG. 21, there is a problem that the switch 33A and the switch 33B connected to the power source 32 must be kept closed to excite bending displacement in the thin plate 31-2.

  Alternatively, as shown in FIG. 22, if the bending of the piezoelectric elements 31-3A and 31-3B is to be aligned clockwise or counterclockwise when viewed from the top 31-1, the piezoelectric elements 31-3A and 31-3B The first electrode of the piezoelectric element 31-3A is connected to the drive circuit 33 so that the first electrode of the piezoelectric element 31-3A has a positive voltage with respect to the first electrode of the piezoelectric element 31-3B, and the piezoelectric element 31-3A and An intermediate potential between the first electrode of the piezoelectric element 31-3A and the first electrode of 31-3B needs to be applied to the thin plate 31-2 which is the second electrode (common electrode) of 31-3B. Thereby, the expansion and contraction of the piezoelectric elements 31-3A and 31-3B could be reversed, and the direction in which the two inclined portions of the thin plate 31-2 were warped could be reversed. However, as a result, the drive voltage applied to the piezoelectric elements 31-3A and 31-3B is reduced, and there is a problem that the drive force and the displacement amount of the piezoelectric actuator are reduced.

  Various combinations of piezoelectric bodies have been proposed for piezoelectric actuators that combine a plurality of piezoelectric bodies and tilt a mirror or the like connected to the piezoelectric bodies in a desired direction. However, according to the disclosure of the present invention, it is possible to move a mirror or the like connected to a piezoelectric body in a desired direction by combining a plurality of piezoelectric elements. The application method is not described, and the change of the driving force or the driving displacement amount of the piezoelectric actuator is not clarified. Therefore, there are still problems to be solved regarding the downsizing of the driving device and the method of applying the voltage.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide electric wires and electrode lands because the first and second bending members have a common electrode and are electrically connected. The drive device can be reduced without applying an intermediate potential of the drive voltage to the common electrode of the bending displacement member at the same time. It is to realize a drive device that can be used.

  A driving apparatus according to the present invention includes a first bending displacement member that excites a first bending displacement by electrical control along a first bending direction orthogonal to a driving direction of a driven body, and is orthogonal to the driving direction. A second bending displacement member in which a second bending displacement is excited by electrical control along the second bending direction, a first bending displacement by the first bending displacement member, and a second bending displacement by the second bending displacement member. And a driving direction conversion member that swings along the driving direction to drive the driven body, wherein the first bending displacement member and the second bending displacement member are each a first piezoelectric member. An element, a first bent electrode provided on one surface of the first piezoelectric element to which a driving voltage is applied, and a first common electrode provided on the other surface of the first piezoelectric element to which a common voltage is applied. And provided on the first bending displacement member. A first common electrode, a first common electrode provided on the second flex movement member is characterized in that characterized in that it is electrically connected.

  According to the configuration, the first bending displacement member and the second bending displacement member include the first piezoelectric element, the first bending electrode to which a driving voltage is applied, and the first bending electrode to which a common voltage is applied. Since the first common electrode is electrically connected to each other, the number of electric wires and electrode lands can be reduced, and the drive device can be reduced in size. The driven body can be driven without applying an intermediate potential of the driving voltage to the common electrode of the bending displacement member, and the driven direction conversion member swings in the driving direction to drive the driven body. The driving direction of the body is orthogonal to the first bending direction and the second bending displacement direction, and it is not necessary to stack the driven body and the driving device in the driving direction, thereby reducing the size and height of the driving device. Has the effect of realizing .

  In the drive device according to the present invention, one end of the first bending displacement member, a fixing portion that fixes one end of the second bending displacement member, and the first bending of the first bending displacement member and the second bending displacement member. When a driving voltage is applied to the electrode and a common voltage is applied to the first common electrode of the first bending displacement member and the second bending displacement member, the first bending displacement member and the second bending displacement member Preferably, the other end is excited with respect to the driven body, and the other is excited to bend away.

  By fixing one end of the first bending displacement member and one end of the second bending displacement member to the fixed portion, bending is excited only at the other end where the bending displacement member is not fixed, and the polarization of the piezoelectric element is further increased. By devising the direction, the bending direction of the bending displacement member can be set to a desired direction. The first bending displacement member and the second bending displacement member have the above-described configuration, and one of the first bending displacement member and the second bending displacement member approaches the driven body and the other moves away. When the bending is excited, there is an additional effect that the driving direction changing member swings in the driven direction.

  In the driving device according to the present invention, each of the first bending displacement member and the second bending displacement member includes a second piezoelectric element provided on a side opposite to the first piezoelectric element of the first common electrode; A second bending electrode provided on a side opposite to the first common electrode of the second piezoelectric element, wherein the first bending displacement member and the second bending displacement member include the first bending electrode and the second bending electrode, respectively. It is preferable that the second bent electrode is electrically connected.

  The first bending displacement member and the second bending displacement member may have a bimorph structure by including the second piezoelectric element and the second bending electrode, and the first bending displacement member and the second bending displacement member. In the bending displacement member, the first bending electrode and the second bending electrode are electrically connected, so that the potential difference of the bending electrode with respect to the common electrode can be made the same, and by setting the polarization direction, the first bending electrode The bending displacement member and the second bending displacement member have an additional effect that the bending is excited so that one of them approaches the driven body and the other moves away.

  In the driving device according to the present invention, each of the first bending displacement member and the second bending displacement member includes a second piezoelectric element provided on a side opposite to the first piezoelectric element of the first bending electrode, A second common electrode provided on the opposite side of the second piezoelectric element from the first bent electrode, wherein the first bent displacement member and the second bent displacement member include the first common electrode and the second bent electrode, respectively. It is preferable that the second common electrode is electrically connected.

  The first bending displacement member and the second bending displacement member may have a bimorph structure by including the second piezoelectric element and the second bending electrode, and the first bending displacement member and the second bending displacement member. In the bending displacement member, the first common electrode and the second common electrode are electrically connected to each other, whereby the potential difference of the common electrode with respect to the bending electrode can be made the same, and by setting the polarization direction, The bending displacement member and the second bending displacement member have an additional effect that the bending is excited so that one of them approaches the driven body and the other moves away.

  In the drive device according to the present invention, it is preferable that the first bent electrode provided on the first bending displacement member and the first bending electrode provided on the second bending displacement member are electrically connected. .

  By electrically connecting the first bent electrode and the second bent electrode, there is an effect that the electric wire and the electrode (electrode land) that can be soldered to the electric wire can be further reduced.

  In the drive device according to the present invention, the first bending displacement member includes a second piezoelectric element provided on the opposite side of the first common electrode to the first piezoelectric element, and the first common of the second piezoelectric element. A second bending electrode provided on the opposite side of the electrode, and the second bending displacement member includes a second piezoelectric element provided on the opposite side of the first bending element to the first piezoelectric element; And a second common electrode provided on the opposite side of the second piezoelectric element from the first bent electrode, wherein the first common electrode provided on the first bent displacement member is the second bent displacement member. The first bent electrode provided on the second bending displacement member is electrically connected to the first and second common electrodes provided on the second bending displacement member. It is preferably electrically connected to the electrode.

  The first bending displacement member and the second bending displacement member may have a bimorph structure by including the second piezoelectric element and the second bending electrode, and are provided in the first bending displacement member. The first common electrode is electrically connected to the first and second common electrodes provided on the second bending displacement member, and the first bending electrode provided on the second bending displacement member is the second bending electrode. By being electrically connected to the first and second bent electrodes provided on the bending displacement member, it is possible to further reduce the number of electrodes (electrode lands) on which the wires and the wires can be soldered. Play.

  As described above, the driving device according to the present invention includes the first and second bending displacement members in which bending displacement is excited by electrical control along the bending direction orthogonal to the driving direction of the driven body, and the driving direction. And a driving direction changing member that swings along the driven body to drive the driven body. The first and second bending displacement members are respectively a first piezoelectric element, a first bending electrode, and a first bending electrode. Having the common electrode and the first common electrode being electrically connected to each other, the number of electric wires and electrode lands can be reduced, and the drive device can be downsized, The driven body can be driven without applying an intermediate potential of the driving voltage to the common electrode of the bending displacement member, and the driven direction conversion member swings in the driving direction to drive the driven body. The driving direction of the body and the first and second bending The displacement direction is perpendicular, an effect that needs to be disposed by stacking the driving device and the driven member in the driving direction without downsizing and low profile of the drive unit can be realized.

  The bending displacement member whose bending displacement is excited by electrical control will be described below with reference to FIGS.

  That is, FIGS. 1A and 1B are schematic views of a bimorph structure piezoelectric body that is a typical device of a bending displacement member. The piezoelectric body shown in FIG. 1 (b) is pressure-bonded (applying adhesive and applying pressure) after sandwiching a shim 21 composed of a material such as a metal between the piezoelectric element 22X and the piezoelectric element 22Y, Furthermore, an electrode 20X and an electrode 20Y made of a material such as a thin metal plate are bonded to the other main surface of the piezoelectric element 22X and the piezoelectric element 22Y. Although voltage can be applied to the shim material 21, the electrode 20X, and the electrode 20Y, as shown in FIG. 1 (b), between the shim material 21 and the electrode 20X and between the shim material 21 and the electrode 20Y, The voltage between is the same.

  In general, a piezoelectric element having a bimorph structure has two piezoelectric elements whose polarizations are set in opposite directions. That is, with reference to FIG. 1B, the polarizations of the piezoelectric element 22X and the piezoelectric element 22Y are set in opposite directions. More specifically, the piezoelectric element 22X is polarized so that it contracts in the length direction when the voltage of the electrode 20X with respect to the shim material 21 is positive and expands when the voltage is negative. The piezoelectric element 22Y is polarized so as to expand in the length direction when the voltage of the electrode 20Y relative to the shim material 21 is positive and to contract when it is negative. In addition, the shim material 21 is being fixed in the one side edge part shown by the black triangle mark in FIG.1 (b).

  In the above configuration, the operation of the piezoelectric body having a bimorph structure will be described as follows with reference to FIG.

  The voltage is applied so that the voltage of the electrode 20X with respect to the shim material 21 and the voltage of the electrode 20Y with respect to the shim material 21 are + V (V). Then, as shown in FIG. 1C, the piezoelectric element 22X contracts in the length direction, and the piezoelectric element 22Y expands in the length direction. The shim material 21 is held at one end at a portion indicated by a black triangle mark in the drawing, and therefore the shim material 21 does not move at the fixing point. As a result, on the non-fixed side, as shown in FIG. 1C, a bending displacement upward in the drawing is excited in the piezoelectric body. On the contrary, the voltage is applied so that the voltage of the electrode 20X with respect to the shim material 21 and the voltage of the electrode 20Y with respect to the shim material 21 become −V (V). Then, the piezoelectric element 22X expands in the length direction, and the piezoelectric element 22Y contracts in the length direction. The shim material 21 is held at one end at a portion indicated by a black triangle mark in the drawing, and therefore the shim material 21 does not move at the fixing point. As a result, at the other end not fixed, although not shown in FIG. 1C, the piezoelectric body is excited to bend downward in the drawing.

  The bending displacement member includes a unimorph-structured piezoelectric body composed of a piezoelectric element layer, a shim material, and electrodes, but the basic operation concept is the same as described above. Further, the bending displacement member described in the present invention refers to a member that is bent and displaced by electrical control such as voltage application, and of course, its structure is limited to dimensions and shapes such as thickness, length, and width. It is not a thing.

  The bending displacement caused by the bending displacement member is considered as a pseudo swinging (turning) motion around the black triangle mark (fulcrum), and the rotation direction is referred to as a swinging (turning) rotation direction. For example, the rocking (turning) rotation direction indicated by an arrow α in FIG. 1 is a clockwise direction when observed from the paper surface side. In the present specification, for the sake of simplification of description, a bending displacement member whose bending displacement is excited by electrical control is simply referred to as a bending displacement member. When the bending displacement member is disposed in the driving device, the moving direction of the driven body is referred to as the driven body moving direction or the width direction (of the bending displacement member), and the direction in which the bending displacement member bends is the bending direction. Alternatively, it is referred to as a thickness direction (of the bending displacement member), and a direction orthogonal to the driven body movement direction (width direction) and orthogonal to the bending direction (thickness direction) is referred to as a length direction (of the bending displacement member). This is not affected by the size of the bending displacement member or the position of the fixing portion of the bending displacement member.

  Next, the form of the drive device to which the present invention is applied will be described below with reference to FIGS. 2, 3A and 3B.

  That is, FIG. 2 is a perspective view in which the drive device according to the embodiment of the present invention is applied to the focus adjustment mechanism of the small camera module housing 6. The drive device according to the present embodiment includes piezoelectric bodies 1A and 1B, an elastic member 2, a friction member 3, a lens barrel (driven body) 4, a guide shaft 5, a camera module housing 6, and drive circuits 7A and 7B. ing.

  The drive device according to the present embodiment includes piezoelectric bodies 1A and 1B having a bimorph structure, and the piezoelectric bodies 1A and 1B are positioned at right angles to each other in the length direction so as to serve also as the wall surface of the housing 6. Has been placed. As shown in FIG. 2, the piezoelectric bodies 1 </ b> A and 1 </ b> B have one end in the length direction (extension of a shim material in this example) fixed to the housing 6 by a method such as fitting or bonding. The other end is connected to an elastic member 2 arranged at a position sandwiched between the piezoelectric bodies 1A and 1B. The elastic member 2 is formed of a member having a relatively low elastic modulus such as metal or resin.

  A method of connecting the piezoelectric bodies 1A and 1B and the elastic member 2 will be described below with reference to FIG.

  The piezoelectric bodies 1A and 1B and the elastic member 2 are connected at connection points M and N indicated by X in the drawing. The connection points M and N are arranged so that a virtual line connecting the connection point M and the connection point N intersects a virtual line parallel to the length direction of the piezoelectric bodies 1A and 1B. The connection point M passes through the center of the piezoelectric body 1A and is located above the imaginary line parallel to the length direction of the piezoelectric body 1A. The connection point N passes through the center of the piezoelectric body 1B and the length of the piezoelectric body 1B. Located below the imaginary line parallel to the direction.

  As shown in FIGS. 2, 3 (a) and 3 (b), a friction member 3 is connected to the elastic member 2. The material of the friction member 3 is selected according to a desired coefficient of friction, such as metal, resin, or carbon.

  In the driving apparatus according to the present embodiment, a cylindrical barrel 4 is arranged as a driven body. As shown in FIG. 2, a cylindrical cavity is formed inside the lens barrel 4, and an optical component such as a lens (not shown) is fitted into the cavity, and the lens thickness direction (optical axis direction) and mirror The driving direction of the cylinder 4 is coincident. In addition, an imaging element such as a CCD (not shown) that captures light representing the imaging target inputted through the lens is disposed between the casing 6 and the lens barrel 4 in the casing 6.

  The lens barrel 4 is in contact with the friction member 3 by friction engagement. Further, a cylindrical guide shaft 5 is fixed to the bottom or ceiling of the housing 6 so that the friction member 3 and the lens barrel 4 are always in contact with each other, and as shown in FIG. It penetrates. The movement of the lens barrel 4 is limited only in the optical axis direction by the guide shaft 5. When the hole member of the lens barrel 4 through which the guide shaft 5 penetrates is not integrated with the lens barrel 4, or friction is applied to give a desired friction coefficient to the contact portion (friction engaging portion) between the lens barrel 4 and the friction member 3 Although the case where an adjustment member is connected or affixed etc. is assumed, a hole member or a friction adjustment member etc. are also called a lens-barrel here.

  The drive device according to the present embodiment includes drive circuits 7A and 7B. The drive circuits 7A and 7B are controlled by an upper control circuit (not shown), and output a voltage or the like corresponding to a drive waveform described later. Although the drive circuit 7A is connected to the piezoelectric body 1A, more specifically, taking the bimorph shown in FIG. 1A as an example, the electrode 20X and the shim material 21 and the electrode 20Y and the shim material 21 are The same voltage difference is set. The same applies to the drive circuit 7B and the piezoelectric body 1B. Thereby, the drive circuit 7A excites the bending displacement of the piezoelectric body 1A by electrical control such as voltage, and the drive circuit 7B also excites the bending displacement of the piezoelectric body 1B by electrical control such as voltage.

  The operation of the driving device driven by the piezoelectric bodies 1A and 1B in the above configuration will be described as follows based on FIG.

  FIG. 3B shows a plan view of FIG. The piezoelectric body 1A is displaced in the direction of an arrow referred to as a bending displacement direction L1 by applying a driving voltage, and a displacement vector is excited in the direction of the arrow referred to as an elastic member displacement direction K1 at a connection point M with the elastic member 2. Is done. The piezoelectric body 1B is displaced in the direction of an arrow referred to as a bending displacement direction L2 by applying a driving voltage, and a displacement vector is excited in the direction of the arrow referred to as an elastic member displacement direction K2 at a connection point N with the elastic member 2. Is done. In addition, although displacement vectors are excited in directions other than the above at the connection points M and N, a description thereof is omitted because the relationship with driving is small.

  Further, the operations of the piezoelectric bodies 1A and 1B and the operations of the elastic member 2 and the friction member 3 associated therewith will be described with reference to FIGS. 4 (a), 4 (b), and 5 as follows.

  That is, FIGS. 4 (a) and 4 (b) show the tip of the friction member 3 (mirror) by driving the piezoelectric bodies 1A and 1B and using the end surface of the friction member 3 fixed to the elastic member 2 as a fulcrum. An example is shown in which the portion that frictionally engages the cylinder 4 is driven in a circular arc, and as a result, the lens barrel 4 is driven. FIG. 5 is a waveform diagram showing an example of a drive voltage waveform applied to the piezoelectric bodies 1A and 1B.

  In the example shown in FIG. 5, the waveform P (drive voltage waveform applied to the piezoelectric body 1A) and the waveform Q (drive voltage waveform applied to the piezoelectric body 1B) are sawtooth drive voltage waveforms, and their phases are relative to each other. The angle is 180 degrees. By simultaneously applying such drive voltage waveforms to the piezoelectric bodies 1A and 1B, the piezoelectric bodies 1A and 1B bend in the bending displacement directions L1 and L2 shown in FIG. Swings in the elastic body displacement directions K1 and K2. The elastic body displacement directions K <b> 1 and K <b> 2 are directions in which either one approaches the lens barrel 4 and the other moves away from the lens barrel 4. That is, the elastic member 2 and the friction member 3 are at the position a in FIG. 4A at the time indicated by a in FIG. 5, at the position b in FIG. 4A in FIG. 4c, the position c in FIG. 4a or c in FIG. 4b, the position d in FIG. 4b in FIG. 5d, and the position e in FIG. 5b in FIG. 5e. Move to position. Therefore, the tip of the friction member 3 (the portion that frictionally engages the lens barrel 4) has an end surface on the side fixed to the elastic member 2 of the friction member 3 as shown in FIGS. As a fulcrum, the swinging motion is repeated in the optical axis direction.

  In the above configuration, the effect of the driving device driven by the piezoelectric bodies 1A and 1B is as follows.

  This will be described with reference to FIG. In the piezoelectric members 1A and 1B and the elastic member 2, an imaginary line connecting the center points of the connection points M and N between the piezoelectric members 1A and 1B and the elastic member 2 is parallel to the length direction of the piezoelectric members 1A and 1B. It is connected so that it intersects with a virtual line. By connecting in this manner, as described above, the tip of the friction member 3 on the lens barrel 4 side swings or arcs (straightly) in the optical axis direction. Since the lens barrel 4 is frictionally engaged with the distal end portion of the friction member 3, the drive is excited in the optical axis direction by the displacement of the friction member 3. That is, the lens barrel 4 is driven in a direction (optical axis direction) different from the bending displacement direction of the piezoelectric bodies 1A and 1B.

  Ideally, the two imaginary lines intersect so as to be orthogonal. The closer the two imaginary lines are to the orthogonal relationship, the closer the imaginary line connecting the center points of the connection points M and N is to the optical axis direction. As a result, based on FIG. 3B, the direction of the displacement vector exerted on the elastic member 2 by the displacement of the piezoelectric bodies 1A and 1B converges in the elastic body displacement directions K1 and K2. Therefore, the bending displacement of the piezoelectric bodies 1A and 1B can be converted into the displacement of the elastic member 2 without waste, and an efficient drive device can be realized.

  Further, the effect of the driving device driven by the piezoelectric bodies 1A and 1B will be described with reference to FIGS. 4A and 4B and FIG.

  As shown in FIG. 5, since a drive voltage having a sawtooth waveform is applied to the piezoelectric bodies 1A and 1B, the tip of the friction member 3 (which is frictionally engaged with the lens barrel 4) in the drive direction and in the opposite direction. There is a speed difference in the angular velocity of (part). That is, a to c have a low angular velocity, and c to e have a high angular velocity. Alternatively, the drive voltage waveform can be set so that a difference occurs in angular acceleration between the drive direction and the opposite direction. Consider a case where the drive voltage is set so that the angular acceleration of displacement is small in the driving direction and the angular acceleration of displacement is large in the opposite direction. In the drive direction, the friction member 3 cannot apply a force exceeding the static friction force to the lens barrel 4 and therefore does not slip, so that the lens barrel 4 is driven by the friction member 3. In the reverse direction, the friction member 3 can apply a force exceeding the static friction force to the lens barrel 4, thereby causing slipping, so that the lens barrel 4 is not driven by the friction member 3. It is also possible to adjust the friction coefficient of the friction member 3, and as a result, the lens barrel 4 can be driven in a desired direction.

  It is also possible to adjust the friction coefficient of the tip (friction engagement portion) of the friction member 3 so that the lens barrel 4 is also driven in the driving direction and the opposite direction. The driving force in the driving direction or in the reverse direction can be determined by the relationship with the dynamic friction force. However, by setting the driving waveform so that the displacement time in the driving direction is long and the displacement time in the reverse direction is short, driving The time during which the dynamic friction force in the direction is applied can be set longer than the time during which the dynamic friction force in the reverse direction is applied. As a result, the lens barrel 4 can be adjusted to be driven in the driving direction.

  Alternatively, the friction member 3 is pressed against the lens barrel 4 using a spring or the like, or the piezoelectric body 1A or 1B is tilted and fixed to the lens barrel 4 side by a predetermined amount, or the lens barrel 4 is fixed to the friction member 3 It is also possible to apply a preload to the friction member 3 by fixing the guide shaft 5 to the housing 6 so as to press it. In this case, the operation of the piezoelectric body 1A or 1B, the elastic member 2, and the friction member 3 is distorted by the preload, and the tip of the friction member 3 that is in frictional engagement with the lens barrel 4 is displaced linearly instead of an arc. You can also Also in this case, it goes without saying that the lens barrel 4 can be driven by the same principle.

  Further, the piezoelectric bodies 1A and 1B are arranged along the wall of the casing 6 or so as to also serve as the wall surface, and the elastic member 2 is arranged at the corner portion of the casing 6 to be formed between the piezoelectric bodies 1A and 1B. A part of the lens barrel 4 is arranged in a virtual fan-shaped space area. As a result, the entire driving device including the lens barrel 4 can be reduced in size and height. At this time, it is needless to say that the piezoelectric bodies 1 </ b> A and 1 </ b> B do not need to be completely along the wall surface of the housing 6 and may be appropriately arranged according to the empty space in the module housing 6. However, it is ideal to arrange the piezoelectric bodies 1A and 1B so as to have a positional relationship of 90 degrees in the longitudinal direction, and this leads to space saving of the driving device.

  As described above, the lens barrel 4 is driven along the guide shaft 5 by the drive mechanism including the piezoelectric bodies 1A and 1B, the elastic member 2, and the friction member 3. Based on this principle, an optical component such as a lens is driven in the optical axis direction to perform focus adjustment. Unlike the prior art shown in FIG. 18, it is not necessary to stack the drive member 302 and the piezoelectric body 301 in the optical axis direction, which is effective in reducing the overall height of the drive device.

In this embodiment, the optical axis direction and the driven body moving direction are treated as synonyms.
(Embodiment 1)
Embodiment 1 of the present invention will be described below with reference to FIG. That is, FIG. 6 shows a plan view of the drive device according to the present embodiment.

  The drive device according to the present embodiment includes piezoelectric bodies 101-1 and 101-2 having a bimorph structure. The piezoelectric element 101-1 is bonded to the piezoelectric elements 101-1 </ b> A and 101-1 </ b> B by sandwiching a shim material 101-1 </ b> E made of a material such as a metal (applying adhesive and applying pressure). Further, thin plate electrodes 101-1C and 101-1D made of a material such as a thin metal plate are pressure-bonded to the other main surfaces of the piezoelectric elements 101-1A and 101-1B. The thin plate electrodes 101-1C and 101-1D are joined to a thin conductive plate material 101-1F (pressure contact, soldering, or integrally formed), and the thin plate electrodes 101-1C and 101-1D are electrically connected. Conducted. The piezoelectric body 101-2 has the same configuration, and includes the piezoelectric elements 101-2A and 101-2B, the thin plate electrodes 101-2C and 101-2D, the shim material 101-2E, and the thin conductive plate 101-2F. It is.

  The driving apparatus according to the present embodiment includes an elastic member 101-4 having conductivity at a position sandwiched between the piezoelectric bodies 101-1 and 101-2. The elastic member 101-4 is joined (press-welded, soldered, or integrally formed) to the shim material 101-1E and the shim material 101-2E. Therefore, the shim material 101-1E and the shim material 101-2E Is electrically conductive.

  As shown in FIG. 6, the piezoelectric bodies 101-1 and 101-2 are arranged inside the housing 101-10 so as to be perpendicular to each other in the length direction so as to serve as the wall surface of the housing 101-10. The shim materials 101-1E and 101-2E are fixed to the casing 101-10 by one-end holding.

  An electric wire 101-7 is soldered to the shim material 101-2E with solder S1. An electric wire 101-8 is soldered to the thin plate electrode 101-2D by solder S2. An electric wire 101-9 is soldered to the thin plate electrode 101-1D by solder S3. The electric wire 101-7 is connected to a terminal on one side of the power source 32, and the electric wires 101-8 and 101-9 are connected to a terminal on the other side of the power source 32. In this way, the voltage waveform applied to the shim material and the voltage waveform applied to the thin plate electrode are out of phase with each other because they are connected to the terminals on both sides of the AC power supply 32, respectively. Between the voltage applied to the material (common voltage) and the voltage applied to the thin plate electrode (drive voltage), a potential difference in which positive and negative are reversed periodically is generated.

  As shown in FIG. 6, a friction member 101-3 is bonded to the elastic member 101-4 in a virtual sector space region formed by the piezoelectric bodies 101-1 and 101-2.

  The driving apparatus according to the present embodiment drives the lens barrel 101-5, which is a driven body, using the bending displacement caused by the piezoelectric bodies 101-1 and 101-2 as a driving source. The lens barrel 101-5 has a substantially cylindrical shape, and a cylindrical cavity is formed in the lens barrel 101-5 as shown in FIG. An optical component such as a lens (not shown) is fitted in the hollow portion. In addition, the lens barrel 101-5 and the friction member 101-3 are brought into contact with each other by frictional engagement, and the lens barrel 101-5 is located at a position facing the friction member 101-3 and the lens barrel 101-5. Two balls 101-6 are attached between the casings 101-10 to reduce friction.

  The operation when the driving device is driven in the above configuration will be described with reference to FIG.

  The piezoelectric element 101-1A is polarized in the direction of arrow C so as to contract and displace in the direction of arrow A when the potential of the electrode 101-1C is higher than the potential of the shim material 101-1E. The piezoelectric element 101-1B is polarized in the direction of arrow D so as to expand and displace in the direction of arrow A when the potential of the electrode 101-1D is higher than the potential of the shim material 101-1E. Piezoelectric element 101-2A is polarized in the direction of the arrow so that it extends and displaces in the direction of arrow when the potential of electrode 101-2C is higher than the potential of shim material 101-2E. The piezoelectric element 101-2B is polarized in the direction of the arrow so that it contracts and displaces in the direction of the arrow when the potential of the electrode 101-2D is higher than the potential of the shim 101-2E.

  Then, a common voltage is applied to the shim materials 101-1E and 101-2E via the electric wire 101-7 and the elastic member 101-4, and the electric wires 101-8 and 101-9 and the conductive plate material 101-1F When a drive voltage is applied to the electrodes 101-1C, 101-1D, 101-2C, and 101-2D via the 101-2F, the common voltage waveform and the drive voltage waveform are out of phase, and the potential difference is a period. Changes. As a result, the piezoelectric bodies 101-1 and 101-2 expand or contract in accordance with the potential difference, and the piezoelectric bodies 101-1 and 101-2 move in the directions indicated by arrows A and C, or vice versa. Bends and displaces. When the same voltage difference is applied between the common electrode of the piezoelectric bodies 101-1 and 101-2 and the other electrodes, the piezoelectric bodies 101-1 and 101 so that the swinging (turning) directions are the same. -2 is polarized. That is, the bending of the piezoelectric bodies 101-1 and 101-2 is excited so that one of the piezoelectric bodies 101-1 and 101-2 approaches and the other moves away from the lens barrel 101-5.

  By applying the common voltage and the drive voltage in this way, the piezoelectric bodies 101-1 and 101-2 have the same swinging (turning) direction, and accordingly, the elastic member 101-4 and the elastic member 101-4 are elastic. The friction member 101-3 connected to the member 101-4 is displaced. 4A and 4B and FIG. 5, the tip of the friction member 101-3 is driven in a circular arc in the direction of the optical axis. By this arc motion, the lens barrel 101-5 as the driven body is driven in the optical axis direction.

  In the above configuration, the effect when the driving device is driven will be described with reference to FIG.

  As described above, since the shim materials 101-1E and 101-2E are electrically connected via the elastic member 101-4, the shim material-side wires and electrodes for supplying electric power from the outside of the driving device. One land is sufficient, and the number of electric wires and electrode lands required for the drive device can be reduced. As a result, the drive device can be reduced in size. Furthermore, by setting the polarization of the piezoelectric bodies 101-1 and 101-2 as described above, the piezoelectric bodies 101-1 and 101-2 have the same swinging (turning) direction from the elastic member 3, and It becomes possible to apply the maximum voltage of the power source to the piezoelectric bodies 101-1 and 101-2. In this way, the displacement amount and displacement generating force of the piezoelectric bodies 101-1 and 101-2 can be increased. As a result, the driving speed is increased, and the size of the piezoelectric element for obtaining the same displacement amount and displacement generation force can be reduced, which contributes to miniaturization of the driving device. Further, as described above, the piezoelectric bodies 101-1 and 101-2 are arranged inside the casing 101-10 so as to be perpendicular to each other in the length direction so as to serve also as the wall surface of the casing 101-10. Thus, a driving device is realized in which the swinging (turning) direction of the piezoelectric bodies 101-1 and 101-2 is perpendicular to the driving direction of the lens barrel 101-5. This makes it possible to reduce the size and height of the entire drive device including the driven body as compared with the conventional drive device in which the displacement (drive) directions of the piezoelectric element and the drive shaft are the same.

The elastic member 101-4 may be integrally formed by cutting, punching, or etching when the shim 101-1E and shim 101-2E are formed. It is not deviated from the embodiment of the present invention even if it is joined while maintaining conductivity such as soldering. Further, the support by the ball 101-6 is merely an example, and the support by the guide shaft may be used as described above. In addition, here, the configuration, operation, and effects of the drive device have been described by taking a bimorph structure bending displacement member as an example. However, as shown in FIG. 7, this embodiment is implemented even with a unimorph structure bending displacement member including the same components. It does not depart from the spirit of the form. In FIG. 7, the same components as those described above with reference to FIG. Therefore, detailed descriptions of these components, operations, and actions are omitted.
(Embodiment 2)
The following describes Embodiment 2 of the present invention with reference to FIG. In FIG. 8, the same components as those described above with reference to FIG. Accordingly, the detailed description of these components, operations, and actions will not be repeated for the same portions as those described above.

  FIG. 8 is a plan view of the drive device according to the present embodiment.

  The elastic member 102-4 is joined (pressed, soldered, or integrally formed) to the thin plate electrodes 101-1D and 101-2D, and the thin plate electrodes 101-1D and 101-2D are electrically connected. Yes. For this reason, the electrodes 101-1C, 101-1D, 101-2C, and 101-2D are kept at the same potential via the conductive plate materials 101-1F and 101-2F. In addition, as shown in FIG. 8, the friction member 101-3 is bonded to the elastic member 102-4 toward the virtual sector space region formed by the piezoelectric bodies 101-20 and 101-21. .

  As shown in FIG. 8, the electric wire 101-11 is soldered to the shim material 102-1E by solder S4. An electric wire 101-7 is soldered to the shim material 102-2E with solder S1. An electric wire 101-8 is soldered to the thin plate electrode 101-2D by solder S2. Further, the electric wire 101-7 and the electric wire 101-11 are connected to a terminal on one side of the power supply 32. The electric wire 101-8 is connected to the terminal on the other side of the power source 32. In this way, the voltage waveform applied to the shim material and the voltage waveform applied to the thin plate electrode are out of phase with each other because they are connected to the terminals on both sides of the AC power supply 32, respectively. Between the voltage applied to the material (driving voltage) and the voltage applied to the thin plate electrode (common voltage), a potential difference in which positive and negative are reversed periodically is generated.

In the above configuration, the operation and effect when the drive device is driven are the same as the operation and effect described above with reference to FIG. Therefore, a detailed description of the operation and action of the drive device shown based on FIG. 8 is omitted. Although the above configuration, operation, and action have been described for the case where a bimorph-structured bending displacement member is used, even the unimorph-structured bending displacement member shown in FIG. 9 departs from the gist of the present embodiment. It is not a thing.
(Embodiment 3)
The following describes Embodiment 3 of the present invention with reference to FIG. In FIG. 10, the same components as those described above with reference to FIG. Accordingly, the detailed description of these components, operations, and actions will not be repeated for the same portions as those described above.

  FIG. 10 is a plan view of the drive device according to the present embodiment.

  The elastic member 102-4 is joined (pressure contact, soldered, or integrally formed) to the thin plate electrodes 101-1D and 101-2D. Further, a thin wire or thin plate (thin film) conductive member 103-11 is joined (pressure-welded, soldered, or integrally formed) to the shim materials 103-1E and 103-2E. Therefore, the shim materials 103-1E and 103-2E are kept at the same potential. The electrodes 101-1C, 101-1D, 101-2C, and 101-2D are kept at the same potential via the conductive plate materials 101-1F and 101-2F. In addition, as shown in FIG. 10, the friction member 101-3 is bonded to the elastic member 102-4 toward the virtual sector space region formed by the piezoelectric bodies 101-30 and 101-31. .

  As shown in FIG. 10, the electric wire 101-7 is soldered to the shim material 103-2E. An electric wire 101-9 is soldered to the thin plate electrode 101-1D. The electric wire 101-7 is connected to a terminal on one side of the power source 32. The electric wire 101-9 is connected to the terminal on the other side of the power source 32. In this way, the voltage waveform applied to the shim material and the voltage waveform applied to the thin plate electrode are out of phase with each other because they are connected to the terminals on both sides of the AC power supply 32, respectively. Between the voltage applied to the material (driving voltage) and the voltage applied to the thin plate electrode (common voltage), a potential difference in which positive and negative are reversed periodically is generated.

  In the above configuration, the operation when the driving device drives is the same as the operation described above with reference to FIG. Therefore, a detailed description of the operation and action of the drive device shown based on FIG. 10 is omitted.

  In the above configuration, the operation when the driving device drives is the same as the operation described above with reference to FIG. 6, but in addition to that, there is only one electrode that can solder the electric wire on the thin plate electrode side and the electric wire. The number of wires and electrode lands on the shim material side may be one, and the number of wires and wires that can be soldered can be further reduced.

  The conductive member 103-11 has been described as being joined by pressure welding or soldering, but of course, the shim materials 103-1E and 103-2E are extended and integrated by cutting, punching, or etching. May be formed. In that case as well, the width of the conductive member may be narrowed so that it does not hinder bending displacement, or it may be processed into a thin line, or the plate thickness may be reduced.

Although the above configuration, operation, and action have been described for the case where a bimorph-structured bending displacement member is used, even the unimorph-structured bending displacement member shown in FIG. 11 departs from the gist of the present embodiment. It is not a thing.
(Embodiment 4)
The following describes Embodiment 4 of the present invention with reference to FIG. In FIG. 12, the same components as those described above with reference to FIG. Accordingly, the detailed description of these components, operations, and actions will not be repeated for the same portions as those described above.

  FIG. 12 is a plan view of the drive device according to the present embodiment.

  The elastic member 101-4 is joined (pressure-welded, soldered, or integrally formed) to the shim materials 101-1E and 101-2E. Further, a thin wire or thin plate (thin film) conductive member 104-11 is joined (pressure-welded, soldered, or integrally formed) to the thin plate electrodes 101-1C and 101-2C. Therefore, the shim materials 101-1E and 101-2E are kept at the same potential. The electrodes 101-1C, 101-1D, 101-2C, and 101-2D are kept at the same potential via the conductive plate materials 101-1F and 101-2F. In addition, as shown in FIG. 12, the friction member 101-3 is bonded to the elastic member 101-4 toward the virtual sector space region formed by the piezoelectric bodies 101-40 and 101-41. .

  As shown in FIG. 12, an electric wire 101-7 is soldered to the shim material 101-2E. An electric wire 101-9 is soldered to the thin plate electrode 101-1D. The electric wire 101-7 is connected to a terminal on one side of the power source 32. The electric wire 101-9 is connected to the terminal on the other side of the power source 32. In this way, the voltage waveform applied to the shim material and the voltage waveform applied to the thin plate electrode are out of phase with each other because they are connected to the terminals on both sides of the AC power supply 32, respectively. Between the voltage applied to the material (common voltage) and the voltage applied to the thin plate electrode (drive voltage), a potential difference in which positive and negative are reversed periodically is generated.

  In the above configuration, the operation when the driving device drives is the same as the operation described above with reference to FIG. Therefore, a detailed description of the operation and action of the drive device shown based on FIG. 12 is omitted.

  In the above configuration, the operation when the driving device drives is the same as the operation described above with reference to FIG. 6, but in addition to that, there is only one electrode that can solder the electric wire on the thin plate electrode side and the electric wire. The number of wires and electrode lands on the shim material side may be one, and the number of wires and wires that can be soldered can be further reduced.

  In addition, the conductive member 104-11 has been described as being joined by pressure welding or soldering, but of course, the thin plate electrode 101-1C or 101-2C is extended and integrated by cutting, punching, or etching. May be formed. In that case as well, the width of the conductive member may be narrowed so that it does not hinder bending displacement, or it may be processed into a thin line, or the plate thickness may be reduced.

Although the above configuration, operation, and action have been described for the case where a bimorph-structured bending displacement member is used, even the unimorph-structured bending displacement member shown based on FIG. 13 departs from the gist of the present embodiment. It is not a thing.
(Embodiment 5)
The following describes Embodiment 5 of the present invention with reference to FIG. 14 and FIG. 14 and 16, the same reference numerals are given to the same components as those described above with reference to FIG. 6. Accordingly, the detailed description of these components, operations, and actions will not be repeated for the same portions as those described above.

  FIG. 14 is a plan view of the drive device according to the present embodiment. FIG. 16 is a perspective view of the drive device in which some of the components such as the lens barrel 101-5 or the housing 101-10 are omitted from FIG.

  As shown in FIG. 16, a thin wire or thin plate (thin film) conductive member 105-11A is joined to the electrode 101-1C and shim material 105-2E by pressure contact or soldering. Further, a thin wire or thin plate (thin film) conductive member 105-11B is joined to the electrode 101-2C and the shim 105-1E by pressure contact or soldering. Therefore, the shim 105-2E and the electrodes 101-1C and 101-1D are kept at the same potential. Similarly, the shim 105-1E and the electrodes 101-2C and 101-2D are kept at the same potential. At this time, the elastic member 105-4 is formed of an insulating material, or if it is formed of a conductive material, it is bonded to either or both of the shim materials 105-1E and 105-2E with an insulating thin film interposed therebetween. It is joined in an electrically insulated state by this method. The polarization directions of the piezoelectric elements 101-2A and 101-2B are different from those in the embodiment shown in FIG. 6, and are polarized in the directions indicated by “c” and “b” in FIG.

  As shown in FIGS. 14 and 16, the shim member 105-1E is soldered with the electric wire 101-11, and the shim member 105-2E is soldered with the electric wire 101-7. The electric wire 101-7 is connected to a terminal on one side of the power source 32. The electric wire 101-11 is connected to the terminal on the other side of the power source 32. In this way, the voltage waveform applied to the shim material and the voltage waveform applied to the thin plate electrode are out of phase with each other because they are connected to the terminals on both sides of the AC power supply 32, respectively. Between the voltage applied to the material (common voltage) and the voltage applied to the thin plate electrode (drive voltage), a potential difference in which positive and negative are reversed periodically is generated.

  In the above configuration, the operation when the driving device drives is the same as the operation described above with reference to FIG. Therefore, a detailed description of the operation and action of the drive device shown based on FIG. 14 is omitted. However, the shim material 105-2E and the electrodes 101-1C and 101-1D, the shim material 105-1E and the electrodes 101-2C and 101-2D are held at the same potential, and the polarization of the piezoelectric body The difference from the above-described embodiment is that the direction is opposite to that of the above-described embodiment. However, there is no difference in the operation itself.

  In the above configuration, the operation when the driving device is driven is the same as the operation described above with reference to FIG. 6, but in addition, in the embodiment shown in FIG. One electric wire and one electrode land may be provided for each of the shim materials 105-1E and 105-2E. In addition, since the electrode land is only on the shim material side, there is an effect that the degree of freedom of the electrode land position is increased. For example, as shown in FIG. 14, the shim materials 102-1E and 102-2E are fixed to the camera module housing 101-10, and a part of the fixed shim material is extended out of the housing so as to extend. Electrode lands can also be provided outside the body.

In the above description, a bending displacement member having a bimorph structure is used. However, even a bending displacement member having a unimorph structure as shown in FIG. 15 does not depart from the gist of the present embodiment.
(Embodiment 6)
Embodiment 6 of the present invention will be described below with reference to FIG.

  That is, FIG. 17 shows a plan view of the drive device according to the present embodiment, but the arrangement of the components of the drive device shown in FIG. 3 is changed. More specifically, as shown in FIG. 17, the piezoelectric bodies 1 </ b> A and 1 </ b> B are horizontally arranged in the length direction so as to serve as one side surface of the housing 6, and accordingly, the positions of the elastic member 2 and the friction member 3 are It moves from the corner of the housing to the center of the side surface to which the piezoelectric bodies 1A and 1B are attached. The piezoelectric bodies 1A and 1B and the elastic member 2 are connected at connection points M and N.

  The lens barrel 4 is in contact with the friction member 3 by friction engagement. Further, a cylindrical guide shaft 5 is fixed to the bottom or ceiling of the housing 6 so that the friction member 3 and the lens barrel 4 are always in contact with each other, and the direction perpendicular to the paper surface of FIG. It penetrates the inside of the lens barrel 4 in the axial direction). The movement of the lens barrel 4 is limited only in the optical axis direction by the guide shaft 5.

  In the above configuration, the operation and effect when the drive device is driven are the same as the operation and effect described above with reference to FIG. Therefore, a detailed description of the operation and action of the drive device shown based on FIG. 17 is omitted. Although the above configuration, operation, and action have been described for the case where a bimorph-structured bending displacement member is used, even the unimorph-structured bending displacement member shown in FIG. 17 departs from the gist of the present embodiment. It is not a thing. Further, as shown here, it goes without saying that the present embodiment does not depend on the facing angle between the two bending displacement members.

  The present invention can be applied to driving of a driven body using an electromechanical conversion element in driving of a lens in an optical apparatus such as a photographing lens of a camera.

(A) is a top view which shows the principal part structure of the piezoelectric element of a bimorph structure, (b) is the schematic which shows the principal part structure of the piezoelectric element of a bimorph structure, (c) is a bimorph structure. It is a figure which shows operation | movement of a piezoelectric element. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a perspective view in which a drive device according to an embodiment of the present invention is applied to a focus adjustment mechanism of a small camera module housing. (A) is a front view which shows the structure of the said drive device, (b) is a top view which shows the structure of the said drive device. (A) (b) is a side view which shows the drive principle of the to-be-driven body by the circular arc motion of a friction member. It is a wave form diagram which shows an example of the drive voltage waveform applied to the bending displacement member provided in the said drive device. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a plan view illustrating a configuration of a main part of a drive device using a piezoelectric body having a bimorph structure. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a plan view illustrating a configuration of a main part of a drive device using a unimorph piezoelectric body. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a plan view illustrating a configuration of a main part of another driving device using a piezoelectric body having a bimorph structure. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of the present invention, and is a plan view illustrating a configuration of a main part of another driving device using a unimorph-structured piezoelectric body. FIG. 9 is a plan view illustrating a configuration of a main part of still another driving device using a piezoelectric body having a bimorph structure according to an embodiment of the present invention. FIG. 9 is a plan view showing a configuration of a main part of still another driving device using a unimorph-structured piezoelectric body according to an embodiment of the present invention. FIG. 9 is a plan view illustrating a configuration of a main part of still another driving device using a piezoelectric body having a bimorph structure according to an embodiment of the present invention. FIG. 9 is a plan view showing a configuration of a main part of still another driving device using a unimorph-structured piezoelectric body according to an embodiment of the present invention. FIG. 9 is a plan view illustrating a configuration of a main part of still another driving device using a piezoelectric body having a bimorph structure according to an embodiment of the present invention. FIG. 9 is a plan view showing a configuration of a main part of still another driving device using a unimorph-structured piezoelectric body according to an embodiment of the present invention. It is the perspective view which extracted a part of component from the said drive device. (A) shows embodiment of this invention and is a front view which shows the principal part structure of the other drive device by the piezoelectric material of a bimorph structure, (b) is the top view. It is sectional drawing for demonstrating the drive device using the conventional electromechanical conversion element. It is a schematic diagram of a piezoelectric actuator using a conventional electromechanical transducer. It is a schematic diagram of a piezoelectric actuator using a conventional electromechanical transducer. It is a schematic diagram of a piezoelectric actuator using a conventional electromechanical transducer. It is a schematic diagram of a piezoelectric actuator using a conventional electromechanical transducer.

Explanation of symbols

2, 101-4, 102-4, 105-4 Elastic member (drive direction changing member)
3, 101-3 Friction member 4, 101-5 Lens barrel (driven body)
5 Guide shaft 6, 101-10 Housing 7A, 7B, 33 Drive circuit 20X, 20Y Electrode 21, 102-1E, 102-2E, 103-1E, 103-2E, 105-1E, 105-2E Shim material 101- 1E, 101-2E shim material (first common electrode)
22X, 22Y, 31-3A, 31-3B, 101-1A, 101-2A Piezoelectric element 101-1B, 101-2B Piezoelectric element (first piezoelectric element)
31-1 Top 31-2 Thin plate 32 Power supply 33A, 33B Switch 1A, 1B, 101-1, 101-2, 101-20, 101-21, 101-30, 101-31, 101-40, 101-41, 301 Piezoelectric body (first and second bending displacement members)
101-1C, 101-2C Thin plate electrode 101-1D, 101-2D Thin plate electrode (first bent electrode)
101-7, 101-8, 101-9, 101-11 Electric wire 101-1F, 101-2F Conductive plate material 101-6 Ball 103-11, 104-11, 105-11A, 105-11B Conductive member S1, S2 , S3, S4 Solder 302 Driving member 304 Lens barrel (driven body)
306 Housing 3011 Lens 3012 Image sensor 3013 Circuit board

Claims (6)

A first bending displacement member in which the first bending displacement is excited by electrical control along a first bending direction orthogonal to the driving direction of the driven body;
A second bending displacement member in which the second bending displacement is excited by electrical control along a second bending direction perpendicular to the driving direction;
A driving direction converting member that swings along the driving direction and drives the driven body based on the first bending displacement by the first bending displacement member and the second bending displacement by the second bending displacement member; With
The first bending displacement member and the second bending displacement member are respectively provided with a first piezoelectric element, a first bending electrode provided on one surface of the first piezoelectric element, to which a driving voltage is applied, and the first bending element. A first common electrode provided on the other surface of one piezoelectric element to which a common voltage is applied;
A driving device, wherein a first common electrode provided on the first bending displacement member and a first common electrode provided on the second bending displacement member are electrically connected. One end of the first bending displacement member and a fixing portion for fixing one end of the second bending displacement member;
When a driving voltage is applied to the first bending electrode of the first bending displacement member and the second bending displacement member, and a common voltage is applied to the first common electrode of the first bending displacement member and the second bending displacement member, 2. The driving device according to claim 1, wherein each of the first bending displacement member and the second bending displacement member is excited to bend so that the other end of the first bending displacement member and the second bending displacement member are closer to each other and away from the other. The first bending displacement member and the second bending displacement member are respectively a second piezoelectric element provided on the opposite side of the first common electrode from the first piezoelectric element, and the first piezoelectric element. A second bent electrode provided on the opposite side to the common electrode;
2. The driving apparatus according to claim 1, wherein each of the first bending displacement member and the second bending displacement member is electrically connected to the first bending electrode and the second bending electrode. The first bending displacement member and the second bending displacement member are respectively a second piezoelectric element provided on the opposite side of the first bending electrode from the first piezoelectric element, and the first bending element. A second common electrode provided on the opposite side of the bending electrode;
2. The driving device according to claim 1, wherein each of the first bending displacement member and the second bending displacement member is electrically connected to the first common electrode and the second common electrode.   5. The driving device according to claim 4, wherein a first bent electrode provided on the first bent displacement member and a first bent electrode provided on the second bent displacement member are electrically connected. The first bending displacement member is provided on a side of the first common electrode opposite to the first piezoelectric element, and on a side of the second piezoelectric element opposite to the first common electrode. A second bent electrode;
The second bending displacement member is provided on a side of the first bending electrode opposite to the first piezoelectric element, and on a side of the second piezoelectric element opposite to the first bending electrode. A second common electrode;
The first common electrode provided on the first bending displacement member is electrically connected to the first and second common electrodes provided on the second bending displacement member,
2. The driving device according to claim 1, wherein the first bending electrode provided on the second bending displacement member is electrically connected to the first and second bending electrodes provided on the second bending displacement member.

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