JP2019146435A - Piezoelectric drive device, method for controlling piezoelectric actuator, robot, electronic component conveying device, printer, and projector - Google Patents

Abstract

To provide a piezoelectric drive device that can increase the driving force and improve control accuracy of a piezoelectric actuator and a method for controlling a piezoelectric actuator, and to provide a robot, an electronic component conveying device, a printer, and a projector including the piezoelectric drive device.SOLUTION: A piezoelectric drive device comprises: a piezoelectric actuator that has a vibration part including piezoelectric elements provided with drive electrodes; a drive circuit that generates drive signals input to the drive electrodes; and a detection circuit that detects vibration of the vibration part on the basis of detection signals output from the drive electrodes.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a piezoelectric drive device, a piezoelectric actuator control method, a robot, an electronic component transport device, a printer, and a projector.

  A piezoelectric actuator provided with a piezoelectric element is known. For example, the vibrator described in Patent Document 1 includes a substrate, a base electrode formed on the substrate, a piezoelectric layer formed on the base electrode, a drive electrode formed on the piezoelectric layer, and A detection electrode.

JP 2009-284375 A

  However, in the vibrator described in Patent Document 1, since the detection electrode is provided separately from the drive electrode, the installation area of the detection electrode and the wiring for the detection electrode must be ensured. There exists a subject that the electrode area of a drive electrode will become small. Further, since the detection electrode is located at a position different from the drive electrode, there is a problem that vibration other than the purpose is easily detected.

A piezoelectric drive device according to an application example of the present invention includes a piezoelectric actuator having a vibration unit including a piezoelectric element provided with a drive electrode;
A drive circuit for generating a drive signal input to the drive electrode;
And a detection circuit that detects vibration of the vibration unit based on a detection signal output from the drive electrode.

It is a top view which shows schematic structure of the piezoelectric drive device (piezoelectric motor) which concerns on 1st Embodiment of this invention. It is a figure for demonstrating operation | movement of the piezoelectric drive device shown in FIG. It is a perspective view of the vibration part, support part, and connection part with which the piezoelectric actuator shown in FIG. 1 is provided. It is the sectional view on the AA line in FIG. FIG. 2 is a plan view of a piezoelectric element provided in the piezoelectric actuator shown in FIG. 1 (viewed from the first diaphragm side). It is a block diagram which shows the structure of the control apparatus with which the piezoelectric drive apparatus shown in FIG. 1 is provided. It is a schematic diagram for demonstrating operation | movement of the control apparatus in 1st Embodiment of this invention. It is a timing chart for demonstrating the other example of operation | movement of the control apparatus in 1st Embodiment of this invention. It is a schematic diagram which shows the control apparatus with which the piezoelectric drive device which concerns on 2nd Embodiment of this invention is provided. It is a perspective view which shows embodiment of the robot of this invention. It is a perspective view which shows embodiment of the electronic component conveying apparatus of this invention. 1 is a perspective view illustrating an embodiment of a printer of the present invention. It is a schematic diagram showing an embodiment of a projector of the present invention.

  Hereinafter, a piezoelectric drive device, a piezoelectric actuator control method, a robot, an electronic component transport device, a printer, and a projector according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

1. Piezoelectric Drive Device <First Embodiment>
FIG. 1 is a plan view showing a schematic configuration of a piezoelectric drive device (piezoelectric motor) according to a first embodiment of the present invention. FIG. 2 is a diagram for explaining the operation of the piezoelectric driving device shown in FIG. FIG. 3 is a perspective view of a vibration section, a support section, and a connection section included in the piezoelectric actuator shown in FIG. 4 is a cross-sectional view taken along line AA in FIG. FIG. 5 is a plan view of the piezoelectric element included in the piezoelectric actuator shown in FIG. 1 (viewed from the first diaphragm side).

  A piezoelectric driving device 100 shown in FIG. 1 is a piezoelectric motor that outputs a rotational force by using an inverse piezoelectric effect. This piezoelectric driving device 100 controls a rotor 110 that is a driven member (driven portion) that can rotate around a rotation axis O, a piezoelectric actuator 1 that contacts the outer peripheral surface 111 of the rotor 110, and driving of the piezoelectric actuator 1. And a control device 10 for performing. In the piezoelectric driving device 100, the piezoelectric actuator 1 transmits the driving force to the rotor 110, so that the rotor 110 rotates (rotates) around the rotation axis O.

  The arrangement of the piezoelectric actuator 1 is not limited to the illustrated position as long as a desired driving force can be transmitted from the piezoelectric actuator 1 to the driven member. For example, the piezoelectric actuator 1 is disposed on the plate surface (bottom surface) of the rotor 110. 1 may be brought into contact. In addition, the piezoelectric driving device 100 may have a configuration in which a plurality of piezoelectric actuators 1 are in contact with one driven member. Further, a plurality of piezoelectric actuators 1 may be stacked and used. In addition, the piezoelectric driving device 100 is not limited to the configuration in which the driven member as illustrated is rotated, and may be configured to linearly move the driven member, for example.

(Piezoelectric actuator)
As shown in FIG. 1, the piezoelectric actuator 1 includes a vibrating portion 11 having a longitudinal shape, a support portion 12, a pair of connecting portions 13 connecting them, and one end portion in the longitudinal direction of the vibrating portion 11. And a transmission portion 14 (convex portion) protruding from the (tip portion). Here, the vibration unit 11 includes the piezoelectric element 4. Moreover, the support part 12 has the intermediate member 5 so that thickness may be equalized with the vibration part 11 (refer FIG. 3).

  The piezoelectric element 4 includes piezoelectric elements 4a, 4b, 4c, 4d, and 4e, and as shown in FIG. 2, the tip of the transmission unit 14 is elliptically moved by the inverse piezoelectric effect. Accordingly, the transmission unit 14 applies a driving force in one direction in the circumferential direction to the outer peripheral surface 111 to rotate the rotor 110 around the rotation axis O. At this time, the vibration of the vibration part 11 is caused by the S-shaped (or inverted S-shaped) bending vibration (lateral vibration) due to the expansion and contraction of the piezoelectric elements 4a and 4d or the piezoelectric elements 4b and 4c, and the vertical vibration due to the expansion and contraction of the piezoelectric element 4e. This is a combination of vibration and vibration. Here, a drive signal is input to one of the piezoelectric elements 4a and 4d or the piezoelectric elements 4b and 4c, and a detection signal (charge) corresponding to the drive state (vibration state) of the vibration unit 11 is output from the other by the piezoelectric effect. Is done. The control device 10 controls the driving of the piezoelectric actuator 1 based on this detection signal. The control device 10 will be described in detail later.

  The transmission unit 14 is made of a material having excellent wear resistance, such as ceramics, and is bonded to the vibration unit 11 with an adhesive or the like. In addition, the shape of the transmission part 14 should just be able to transmit the driving force of the piezoelectric actuator 1 to the rotor 110 (driven member), and is not limited to the shape of illustration.

  Such a piezoelectric actuator 1 has a laminated structure as shown in FIG. That is, as shown in FIG. 3, the vibration part 11, the support part 12, and the connection part 13 are composed of the first vibration plate 2, the second vibration plate 3, the piezoelectric element 4 and the intermediate member disposed therebetween. And 5. The first diaphragm 2 is bonded to the piezoelectric element 4 and the intermediate member 5 via an adhesive 61. Similarly, the second diaphragm 3 is joined to the piezoelectric element 4 and the intermediate member 5 via an adhesive 62. Hereinafter, each part of the piezoelectric actuator 1 will be described sequentially.

  The 1st diaphragm 2 and the 2nd diaphragm 3 have comprised the planar view shape corresponding to the vibration part 11, the support part 12, and the connection part 13 which were mentioned above, respectively. The first diaphragm 2 and the second diaphragm 3 have a portion (vibrating portion) sandwiching the piezoelectric element 4, and a laminate including the portion and the piezoelectric element 4 constitutes the vibrating portion 11. . Further, the first diaphragm 2 and the second diaphragm 3 have a portion that sandwiches the intermediate member 5, and the laminate including the portion and the intermediate member 5 constitutes the support portion 12. Note that neither the piezoelectric element 4 nor the intermediate member 5 is disposed in the connecting portion 13, and the thickness of the piezoelectric element 4 or the intermediate member 5 is between the first diaphragm 2 and the second diaphragm 3. A corresponding gap is formed.

  The first diaphragm 2 and the second diaphragm 3 are not particularly limited. For example, a semiconductor substrate such as a silicon substrate or a silicon carbide substrate can be used. By using a semiconductor substrate (particularly a silicon substrate) as the first diaphragm 2 or the second diaphragm 3, the first diaphragm 2 or the second diaphragm 3 can be produced with high productivity and high accuracy by a silicon wafer process (MEMS process). Can be manufactured.

  An insulating layer 24 is provided on the surface of the first diaphragm 2 on the piezoelectric element 4 side (upper side in FIG. 4). Thereby, a short circuit of the wiring layer 7 via the first diaphragm 2 can be reduced. Similarly, an insulating layer 34 is provided on the surface of the second diaphragm 3 on the piezoelectric element 4 side (lower side in FIG. 4). Thereby, a short circuit of the wiring layer 8 via the second diaphragm 3 can be reduced. Insulating layers 24 and 34 are silicon oxide films formed by thermally oxidizing the surface of a silicon substrate, for example, when a silicon substrate is used for each of first diaphragm 2 and second diaphragm 3. The insulating layers 24 and 34 are not limited to silicon oxide films formed by thermal oxidation, but may be silicon oxide films formed by, for example, a CVD method using TEOS (tetraethoxysilane). The insulating layers 24 and 34 are not limited to silicon oxide films as long as they have insulating properties. For example, inorganic films such as silicon nitride films, epoxy resins, urethane resins, urea resins, melamines, etc. It may be an organic film made of various resin materials such as resin, phenol resin, ester resin, and acrylic resin. Furthermore, the insulating layers 24 and 34 may each be a laminated film of a plurality of layers made of different materials.

  A wiring layer 7 is arranged on the insulating layer 24 of the first diaphragm 2. The wiring layer 7 includes a plurality of first electrodes 71 (wiring electrodes) disposed in the vibration portion 11 and a plurality of first electrodes disposed from the plurality of first electrodes 71 to the support portion 12 via the connection portion 13. 1 wiring 72 (see FIG. 4). These are formed in a lump by a known film forming process, for example.

  The plurality of first electrodes 71 are provided corresponding to the above-described piezoelectric elements 4a, 4b, 4c, 4d, and 4e, and the corresponding piezoelectric elements 4a, 4b, 4c, 4d, and 4e (more specifically, the first elements described later). 1 electrode 42a, 42b, 42c, 42d, 42e). The plurality of first wirings 72 are provided corresponding to the plurality of first electrodes 71, and are each routed from the corresponding first electrode 71 to the end of the support portion 12. In addition, a terminal 91 that is electrically connected to a substrate (not shown) is connected to the end of each first wiring 72 via a wiring 53 on the intermediate member 5 (see FIG. 4). Note that the terminal 91 may be provided directly at the end of each first wiring 72.

  On the other hand, the wiring layer 8 is disposed on the insulating layer 34 of the second diaphragm 3. As shown in FIG. 4, the wiring layer 8 includes a second electrode 81 disposed in the vibration part 11 and a second wiring 82 disposed from the second electrode 81 to the support part 12 via the connection part 13. And having. These are formed in a lump by a known film forming process, for example.

  The second electrode 81 is electrically connected to the above-described piezoelectric element 4 (more specifically, the second electrode 43 described later). The second wiring 82 is routed to the end of the support portion 12. Further, a terminal 92 that is electrically connected to a substrate (not shown) is provided at the end of the second wiring 82 (see FIG. 4).

  The constituent materials of the wiring 53, the wiring layers 7 and 8, and the terminals 92 and 91 are not particularly limited. For example, aluminum (Al), nickel (Ni), gold (Au), platinum (Pt), copper ( Examples thereof include metal materials such as Cu), titanium (Ti), and tungsten (W). The terminal 92 can be formed using a known film formation method.

  The first diaphragm 2 and the second diaphragm 3 as described above are joined to the piezoelectric element 4 and the intermediate member 5 by adhesives 61 and 62. Here, the adhesive 61 joins the first diaphragm 2 and the piezoelectric element 4 so as to allow electrical connection between the wiring layer 7 and the piezoelectric element 4. Further, the adhesive 62 joins the second diaphragm 3 and the piezoelectric element 4 so as to allow electrical connection between the wiring layer 8 and the piezoelectric element 4. The adhesives 61 and 62 are not particularly limited. For example, various adhesives such as epoxy, acrylic, and silicon, anisotropic conductive adhesives, and the like can be used.

  As shown in FIG. 5, the piezoelectric element 4 includes a plate-like piezoelectric body 41, a first electrode 42 (drive electrode) disposed on one surface of the piezoelectric body 41 (on the first diaphragm 2 side), and And a second electrode 43 (ground electrode) disposed on the other surface (the second diaphragm 3 side) of the piezoelectric body 41.

  The piezoelectric body 41 has a rectangular shape in plan view. Examples of the constituent material of the piezoelectric body 41 include lead zirconate titanate (PZT), barium titanate, lead titanate, potassium niobate, lithium niobate, lithium tantalate, sodium tungstate, zinc oxide, titanate. Examples thereof include piezoelectric ceramics such as barium strontium (BST), strontium bismuth tantalate (SBT), lead metaniobate, and lead scandium niobate. In addition to the above-described piezoelectric ceramics, polyvinylidene fluoride, quartz, or the like may be used as the constituent material of the piezoelectric body 41.

  The piezoelectric body 41 may be formed from, for example, a bulk material, or may be formed using a sol-gel method or a sputtering method, but is preferably formed from a bulk material. Thereby, the thickness of the piezoelectric body 41 can be increased and the displacement amount of the piezoelectric element 4 can be increased. Therefore, the current efficiency of the piezoelectric actuator 1 can be further improved.

  The first electrode 42 (drive electrode) is a plurality (five) of first electrodes 42a, 42b, 42c, 42d, 42e, which are individual electrodes provided for each of the piezoelectric elements 4a, 4b, 4c, 4d, 4e. It consists of A drive signal (drive voltage) is input to each of the first electrodes 42a, 42b, 42c, 42d, and 42e. The first electrodes 42 a, 42 b, 42 c, 42 d, 42 e each output a detection signal corresponding to the driving state of the piezoelectric element 4. On the other hand, the second electrode 43 (ground electrode) is a common electrode provided in common to the piezoelectric elements 4a, 4b, 4c, 4d, and 4e, and is electrically connected to a constant potential (for example, a ground potential).

  That is, the piezoelectric element 4 a includes the piezoelectric body 41, the first electrode 42 a and the second electrode 43. Similarly, the piezoelectric elements 4b, 4c, 4d, and 4e include a piezoelectric body 41, first electrodes 42b, 42c, 42d, and 42e, and a second electrode 43. Thus, the piezoelectric element 4 has five piezoelectric elements 4a, 4b, 4c, 4d, and 4e.

  Here, of the first electrodes 42a, 42b, 42c, 42d, and 42e, the first electrodes 42a, 42b, 42c, and 42d have an electric field that causes the piezoelectric body 41 to bend and vibrate (the lateral vibration described above) by the input of the drive signal. This is a bending electrode generated between the second electrode 43 and the second electrode 43. On the other hand, the first electrode 42e is an electrode for longitudinal vibration that generates an electric field between the second electrode 43 and the piezoelectric body 41 without causing the piezoelectric body 41 to bend and vibrate (the longitudinal vibration described above) without being bent. .

  In the present embodiment, the first electrode 42 e is disposed along the longitudinal direction of the piezoelectric body 41 at the center in the width direction of the piezoelectric body 41. The first electrodes 42a and 42b are arranged along the longitudinal direction of the piezoelectric body 41 on one side in the width direction of the piezoelectric body 41 with respect to the first electrode 42e. The first electrodes 42c and 42d are arranged along the longitudinal direction of the piezoelectric body 41 on the other side in the width direction of the piezoelectric body 41 with respect to the first electrode 42e.

  The piezoelectric body 41 is integrally configured in common with the piezoelectric elements 4a, 4b, 4c, 4d, and 4e, but is provided separately for each of the piezoelectric elements 4a, 4b, 4c, 4d, and 4e. It may be done.

  The constituent materials of the first electrode 42 and the second electrode 43 are not particularly limited. For example, aluminum (Al), nickel (Ni), gold (Au), platinum (Pt), iridium (Ir), copper Examples thereof include metal materials such as (Cu), titanium (Ti), and tungsten (W).

  The intermediate member 5 is provided between the first diaphragm 2 and the second diaphragm 3 in the support portion 12 described above, and has substantially the same shape and size as the support portion 12 in plan view. Yes. The intermediate member 5 reinforces the support portion 12 and sets the distance between the first diaphragm 2 and the second diaphragm 3 in the support portion 12 to the first diaphragm 2 and the second diaphragm 3 in the vibration portion 11. It has the function to regulate so that it may become equal to the distance between.

  As shown in FIG. 4, the intermediate member 5 includes a main body 51 and an insulating layer 52 provided on the main body 51. In such an intermediate member 5, for example, the main body 51 is made of silicon, and the insulating layer 52 is made of a silicon oxide film. In addition, as a constituent material of the intermediate member 5, it is not limited to this, For example, you may use various ceramics, such as a zirconia, an alumina, and a titania, various resin materials.

(Control device)
FIG. 6 is a block diagram illustrating a configuration of a control device included in the piezoelectric driving device illustrated in FIG. 1. FIG. 7 is a schematic diagram for explaining the operation of the control device according to the first embodiment of the present invention.

  As illustrated in FIG. 6, the control device 10 includes a drive circuit 101, a detection circuit 102, a switch 103, and a control unit 104.

  The drive circuit 101 is a circuit that generates a drive signal for driving the piezoelectric actuator 1. Specifically, the drive circuit 101 includes a first drive circuit 101a, a second drive circuit 101b, and a third drive circuit 101c. The first drive circuit 101a generates drive signals that are input to the first electrodes 42b and 42c (first drive electrodes) of the piezoelectric elements 4b and 4c of the piezoelectric actuator 1. The second drive circuit 101 b generates drive signals that are input to the first electrodes 42 a and 42 d (second drive electrodes) of the piezoelectric elements 4 a and 4 d of the piezoelectric actuator 1. The third drive circuit 101 c generates a drive signal that is input to the first electrode 42 e (third drive electrode) of the piezoelectric element 4 e of the piezoelectric actuator 1. Each of the first drive circuit 101a, the second drive circuit 101b, and the third drive circuit 101c includes, for example, an oscillation circuit and an amplification circuit, and amplifies a signal from the oscillation circuit by the amplification circuit. A drive signal is generated. Here, the drive signal is a signal whose voltage value periodically changes. The waveform of the drive signal is not particularly limited, and examples thereof include a sine waveform and a rectangle.

  The detection circuit 102 is a circuit that detects the vibration of the vibration unit 11 based on the detection signal from the piezoelectric actuator 1. Specifically, the detection circuit 102 includes a first detection circuit 102a, a second detection circuit 102b, and a third detection circuit 102c. The first detection circuit 102 a detects the vibration of the vibration unit 11 based on detection signals output from the first electrodes 42 b and 42 c (first drive electrodes) of the piezoelectric elements 4 b and 4 c of the piezoelectric actuator 1. The second detection circuit 102b detects the vibration of the vibration unit 11 based on detection signals output from the first electrodes 42a and 42d (second drive electrodes) of the piezoelectric elements 4a and 4d of the piezoelectric actuator 1. The third detection circuit 102c detects the vibration of the vibration unit 11 based on the detection signal output from the first electrode 42e (third drive electrode) of the piezoelectric element 4e of the piezoelectric actuator 1. Each of the first detection circuit 102a, the second detection circuit 102b, and the third detection circuit 102c is configured to include a phase comparator that outputs a signal corresponding to the phase difference between the detection signal and the drive signal, for example. ing.

  The switch 103 is a circuit that causes the drive signal necessary for driving the piezoelectric actuator 1 among the drive signals from the drive circuit 101 to be input to the piezoelectric actuator 1 and blocks other drive signals. Specifically, the switch 103 includes a first switch 103a, a second switch 103b, and a third switch 103c. The first switch 103a is provided between the first electrodes 42b and 42c (first drive electrode) and the first drive circuit 101a, and switches between a conduction state and a cutoff state. The second switch 103b is provided between the first electrodes 42a and 42d (second drive electrodes) and the second drive circuit 101b, and switches between a conduction state and a cutoff state. The third switch 103c is provided between the first electrode 42e (third drive electrode) and the third drive circuit 101c, and switches between a conduction state and a cutoff state. The first switch 103a, the second switch 103b, and the third switch 103c are not particularly limited, and various switches can be used.

  The control unit 104 has a function of controlling each unit in the control device 10. In particular, the control unit 104 has a function of controlling the drive of the drive circuit 101 based on the detection result of the detection circuit 102. Such a control unit 104 has, for example, a processor and a memory in which commands that can be read by the processor are stored, and the processor reads various commands from the memory and executes them to implement various functions. .

  In the control device 10 configured as described above, for example, when the rotor 110 is rotated in the direction α shown in FIG. 7, the second switch 103 b and the third switch 103 c are turned on and the first switch 103 a is set. Is shut off. As a result, the drive signal from the second drive circuit 101 b is input to the first electrodes 42 a and 42 d of the piezoelectric elements 4 a and 4 d of the piezoelectric actuator 1, and the drive signal from the third drive circuit 101 c is applied to the piezoelectric actuator 1. It is input to the first electrode 42e of the element 4e. At this time, the control apparatus 10 detects the vibration of the vibration part 11 using the 1st detection circuit 102a. The first detection circuit 102 a detects the vibration of the vibration unit 11 based on detection signals output from the first electrodes 42 b and 42 c of the piezoelectric elements 4 b and 4 c of the piezoelectric actuator 1. Here, since the first switch 103a is in the cut-off state, the drive signal from the first drive circuit 101a is not superimposed on the detection signal output from the first electrodes 42b and 42c.

  On the contrary, when the rotor 110 is rotated in the direction β, the first switch 103a and the third switch 103c are turned on, and the second switch 103b is turned off. As a result, the drive signal from the first drive circuit 101 a is input to the first electrodes 42 b and 42 c of the piezoelectric elements 4 b and 4 c of the piezoelectric actuator 1, and the drive signal from the third drive circuit 101 c is applied to the piezoelectric actuator 1. It is input to the first electrode 42e of the element 4e. At this time, the control apparatus 10 detects the vibration of the vibration part 11 using the 2nd detection circuit 102b. The second detection circuit 102b detects the vibration of the vibration unit 11 based on detection signals output from the first electrodes 42a and 42d of the piezoelectric elements 4a and 4d of the piezoelectric actuator 1. Here, since the second switch 103b is in the cut-off state, the drive signal from the second drive circuit 101b is not superimposed on the detection signal output from the first electrodes 42a and 42d.

  As described above, when the piezoelectric actuator 1 is driven, the first electrode 42e, the third drive circuit 101c, and the third detection circuit 102c of the piezoelectric element 4e may be omitted. Further, by appropriately shifting the phases of the drive signal from the first drive circuit 101a and the drive signal from the second drive circuit 101b, both the drive signals are input to the piezoelectric actuator 1 so that the rotor 110 can be moved in the direction α. Or it can be rotated in the direction β. In this case, the first switch 103a and the second switch 103b may be turned on, the third switch 103c may be turned off, and the vibration of the vibration unit 11 may be detected using the third detection circuit 102c.

  As described above, the piezoelectric drive device 100 generates the drive signal input to the first electrode 42 and the piezoelectric actuator 1 having the vibration unit 11 including the piezoelectric element 4 provided with the first electrode 42 (drive electrode). And a detection circuit 102 that detects the vibration of the vibration unit 11 based on a detection signal output from the first electrode 42. The method for controlling the piezoelectric actuator 1 having the vibration unit 11 including the piezoelectric element 4 provided with the first electrode 42 (drive electrode) drives the piezoelectric element 4 by inputting a drive signal to the first electrode 42. Based on the detection signal output from the first electrode 42, the vibration of the vibration unit 11 is detected.

  According to the piezoelectric driving device 100 or the control method as described above, the detection circuit 102 detects the vibration of the vibration unit 11 based on the detection signal output from the first electrode 42 that is the driving electrode. These electrodes and wiring need not be provided separately from the first electrode 42 on the piezoelectric element 4. Therefore, the driving force of the piezoelectric actuator 1 can be increased by increasing the electrode area of the first electrode 42. Moreover, since a detection signal is output from the 1st electrode 42 which is a drive electrode, it can reduce that the vibrations other than the objective of the vibration part 11 are detected. Therefore, the control accuracy of the piezoelectric actuator 1 is controlled by controlling the drive of the drive circuit 101 using the detection result of the detection circuit 102 as compared with the case where the detection signal output from the electrode provided separately from the drive electrode is used. Can be increased.

  Here, the piezoelectric element 4 includes piezoelectric elements 4b and 4c that are first piezoelectric elements that flexurally vibrate the vibration part 11 to one side, and a piezoelectric element 4a that is a second piezoelectric element that flexibly vibrates the vibration part 11 to the other side. 4d. The first electrode 42 (drive electrode) includes first electrodes 42b and 42c that are first drive electrodes provided on the piezoelectric elements 4b and 4c (first piezoelectric elements), and piezoelectric elements 4a and 4d (second piezoelectric elements). The first electrodes 42a and 42d, which are the second drive electrodes, are provided. Thereby, the vibration part 11 can be flexibly vibrated. Therefore, the rotor 110 (driven member) can be rotated by the driving force from the piezoelectric actuator 1.

  In the present embodiment, the piezoelectric element 4 has a first state in which a drive signal is input to the first electrodes 42b and 42c (first drive electrode), and a drive signal to the first electrodes 42a and 42d (second drive electrode). The input second state is switched. When the detection circuit 102 is in the first state, the detection circuit 102 detects the vibration of the vibration unit 11 based on the detection signals output from the first electrodes 42a and 42d, and when the detection circuit 102 is in the second state, the first electrode 42b, Based on the detection signal output from 42c, the vibration of the vibration part 11 is detected. Thereby, the detection circuit 102 can obtain a detection signal on which the drive signal is not superimposed.

  In addition, the drive circuit 101 is input to the first drive circuit 101a that generates a drive signal input to the first electrodes 42b and 42c (first drive electrode) and the first electrodes 42a and 42d (second drive electrode). And a second drive circuit 101b for generating a drive signal. Accordingly, it is possible to input a drive signal to a necessary electrode among the first electrodes 42b and 42c and the first electrodes 42a and 42d without providing a switch as in the second embodiment described later.

  The piezoelectric drive device 100 of the present embodiment includes a first switch 103a provided between the first electrodes 42b and 42c (first drive electrode) and the first drive circuit 101a, and the first electrodes 42a and 42d (second drive). Drive switch) and a second switch 103b provided between the second drive circuit 101b. When the first switch 103a is in a conductive state, the second switch 103b is in a cut-off state. On the other hand, when the first switch 103a is in a cut-off state, the second switch 103b is in a conductive state. Thereby, it is possible to reduce the unnecessary components such as noise from being mixed into the detection signal from the first drive circuit 101a or the second drive circuit 101b.

  The detection circuit 102 includes a first detection circuit 102a that detects vibration of the vibration unit 11 based on detection signals output from the first electrodes 42b and 42c (first drive electrodes), and first electrodes 42a and 42d ( And a second detection circuit 102b that detects the vibration of the vibration unit 11 based on the detection signal output from the second drive electrode). Thereby, it is possible to obtain a detection signal output from a necessary electrode among the first electrodes 42b and 42c and the first electrodes 42a and 42d without providing a switch as in the second embodiment.

(Modification 1)
FIG. 8 is a timing chart for explaining another example of the operation of the control device according to the first embodiment of the present invention.

  In the above-described embodiment, one of the first switch 103a and the second switch 103b is in a conducting state and the other is in a blocking state, and one of the piezoelectric elements 4a, 4d and the piezoelectric elements 4b, 4c is used for driving and the other is used for driving. The case where it is used for detection has been described. In the present modification, any one of the first switch 103a, the second switch 103b, and the third switch 103c described above is brought into a cut-off state only when the vibration unit 11 is detected. In particular, as shown in FIG. 8, the switch is periodically turned off (OFF in the figure).

  More specifically, for example, the phases of the drive signal from the first drive circuit 101a and the drive signal from the second drive circuit 101b are appropriately shifted so that the rotor 110 rotates in the direction α or the direction β. Each of the first switch 103a and the second switch 103b is turned on, and both drive signals are input to the piezoelectric actuator 1. In addition, the third switch 103c is periodically alternately switched between a conductive state and a cut-off state. When the third switch 103c is in a cut-off state, the vibration of the vibration unit 11 is detected using the detection signal output from the first electrode 42e. Is detected.

  As described above, the first period (the ON period in the figure) in which the drive signal is input to the first electrode 42 (drive electrode) and the second period (the OFF period in the figure) that is not input are alternately and periodically repeated. And the vibration of the vibration part 11 is detected based on the detection signal in a 2nd period. Here, the piezoelectric drive device 100 includes a switch 103 that is provided between the first electrode 42 (drive electrode) and the drive circuit 101 and alternately and periodically switches between a conductive state and a cutoff state. Then, the detection circuit 102 detects the vibration of the vibration unit 11 based on the detection signal when the switch 103 is in the cutoff state. As a result, it is possible to obtain a detection signal on which a drive signal is not superimposed while driving as many piezoelectric elements as possible.

  Here, it is preferable that the first period is not less than 10 times and not more than 100 times the period of the drive signal. Thereby, the detection accuracy of the vibration of the vibration part 11 can be improved. In addition, it is preferable that the second period is 1 time to 3 times the period of the drive signal. Thereby, attenuation of the vibration of the vibration part 11 in the second period can be reduced. Note that the lengths of the first period and the second period may be the same or different.

(Modification 2)
In the embodiment and the modification described above, the case where the switch 103 is operated so that the drive signal is not superimposed on the detection signal has been described. Is known, a signal corresponding to the vibration state of the vibration part 11 can be obtained by removing the component of the drive signal.

  In the present modification, vibration of the vibration unit 11 is detected based on a detection signal in a state where a drive signal is input to the first electrode 42 (drive electrode). Here, the detection circuit 102 generates a correction signal obtained by removing a component corresponding to the drive signal from the detection signal, and detects the vibration of the vibration unit 11 based on the correction signal. As a result, it is possible to obtain a detection signal on which a drive signal is not superimposed while driving as many piezoelectric elements as possible.

Second Embodiment
FIG. 9 is a schematic diagram illustrating a control device included in the piezoelectric driving device according to the second embodiment of the present invention. In the following description, the present embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted. In FIG. 9, the same reference numerals are given to the same configurations as those in the above-described embodiment.

  A piezoelectric drive device 100A illustrated in FIG. 9 includes a control device 10A that controls the drive of the piezoelectric actuator 1. The control device 10A includes a drive circuit 101A, a detection circuit 102A, and switches 103A and 105.

  The drive circuit 101A includes a first drive circuit 101a and a third drive circuit 101c. The first drive circuit 101a of the present embodiment generates drive signals that are input to the first electrodes 42a, 42b, 42c, and 42d of the piezoelectric elements 4a, 4b, 4c, and 4d of the piezoelectric actuator 1.

  The detection circuit 102A includes a first detection circuit 102a. The first detection circuit 102a of the present embodiment is based on a detection signal output from one of the first electrodes 42a, 42b, 42c, 42d, and 42e of the piezoelectric elements 4a, 4b, 4c, 4d, and 4e of the piezoelectric actuator 1. Then, the vibration of the vibration unit 11 is detected.

  The switch 103A includes a first switch 103a, a second switch 103b, and a third switch 103c. The second switch 103b of the present embodiment is provided between the first electrodes 42a and 42d and the first drive circuit 101a, and switches between a conduction state and a cutoff state.

  The switch 105 is a circuit for inputting a necessary detection signal among the detection signals from the piezoelectric actuator 1 to the detection circuit 102A. Specifically, the switch 105 includes a first switch 105a, a second switch 105b, and a third switch 105c. The first switch 105a is provided between the first electrodes 42a and 42d and the detection circuit 102A, and switches between a conduction state and a cutoff state. The second switch 105b is provided between the first electrodes 42b and 42c and the detection circuit 102A, and switches between a conduction state and a cutoff state. The third switch 105c is provided between the first electrode 42e and the detection circuit 102A, and switches between a conduction state and a cutoff state. The first switch 105a, the second switch 105b, and the third switch 105c are not particularly limited, and various switches can be used.

  For example, when the rotor 110 is rotated in the direction α shown in FIG. 9, the control device 10 </ b> A configured as described above makes the second switches 103 b and 105 b and the third switch 103 c conductive, The switches 103a and 105a and the third switch 105c are turned off. As a result, the drive signal from the first drive circuit 101 a is input to the first electrodes 42 a and 42 d of the piezoelectric elements 4 a and 4 d of the piezoelectric actuator 1, and the drive signal from the third drive circuit 101 c is applied to the piezoelectric actuator 1. It is input to the first electrode 42e of the element 4e. At this time, 10 A of control apparatuses detect the vibration of the vibration part 11 using the 1st detection circuit 102a. The first detection circuit 102 a detects the vibration of the vibration unit 11 based on detection signals output from the first electrodes 42 b and 42 c of the piezoelectric elements 4 b and 4 c of the piezoelectric actuator 1. Here, since the first switches 103a and 105a and the third switch 105c are in the cut-off state, the drive signal from the first drive circuit 101a is superimposed on the detection signal output from the first electrodes 42b and 42c. There is no.

  On the other hand, when the rotor 110 is rotated in the direction β, the first switches 103a and 105a and the third switch 103c are turned on, and the second switches 103b and 105b and the third switch 105c are turned off. As a result, the drive signal from the first drive circuit 101 a is input to the first electrodes 42 b and 42 c of the piezoelectric elements 4 b and 4 c of the piezoelectric actuator 1, and the drive signal from the third drive circuit 101 c is applied to the piezoelectric actuator 1. It is input to the first electrode 42e of the element 4e. At this time, 10 A of control apparatuses detect the vibration of the vibration part 11 using the 1st detection circuit 102a. The first detection circuit 102 a detects the vibration of the vibration unit 11 based on detection signals output from the first electrodes 42 a and 42 d of the piezoelectric elements 4 a and 4 d of the piezoelectric actuator 1. Here, since the second switches 103b and 105b and the third switch 105c are in the cut-off state, the drive signal from the first drive circuit 101a is superimposed on the detection signal output from the first electrodes 42a and 42d. There is no.

  Also by the second embodiment as described above, the same effect as that of the first embodiment described above can be obtained.

2. Next, an embodiment of the robot of the present invention will be described.

FIG. 10 is a perspective view showing an embodiment of the robot of the present invention.
The robot 1000 shown in FIG. 10 can perform operations such as feeding, removing, transporting and assembling precision instruments and parts (objects) constituting the precision instruments. The robot 1000 is a six-axis robot, and includes a base 1010 fixed to a floor or a ceiling, an arm 1020 rotatably connected to the base 1010, an arm 1030 rotatably connected to the arm 1020, and an arm 1030. An arm 1040 that is pivotally connected to the arm 1040, an arm 1050 that is pivotally coupled to the arm 1040, an arm 1060 that is pivotally coupled to the arm 1050, and a arm 1060 that is pivotally coupled to the arm 1060. An arm 1070 and a control unit 1080 that controls driving of the arms 1020, 1030, 1040, 1050, 1060, and 1070 are provided. Further, the arm 1070 is provided with a hand connection unit, and an end effector 1090 corresponding to an operation to be executed by the robot 1000 is attached to the hand connection unit. In addition, the piezoelectric drive device 100 is mounted on all or a part of each joint portion, and the arms 1020, 1030, 1040, 1050, 1060, and 1070 are rotated by driving the piezoelectric drive device 100. . The driving of each piezoelectric driving device 100 is controlled by the control unit 1080. Instead of the piezoelectric driving device 100, a piezoelectric driving device 100A may be used.

  The robot 1000 as described above includes the piezoelectric driving device 100. According to such a robot 1000, the driving force of the piezoelectric actuator 1 can be increased, and the control accuracy of the piezoelectric actuator 1 can be increased. Therefore, the robot 1000 can be reduced in size and weight, and the control accuracy of the robot 1000 can be increased.

3. Next, an embodiment of the electronic component conveying device of the present invention will be described.

  FIG. 11 is a perspective view showing an embodiment of the electronic component carrying apparatus of the present invention. In the following, for convenience of explanation, the three axes orthogonal to each other are referred to as an X axis, a Y axis, and a Z axis.

  An electronic component conveying apparatus 2000 shown in FIG. 11 is applied to an electronic component inspection apparatus, and includes a base 2100 and a support base 2200 disposed on the side of the base 2100. Further, on the base 2100, the upstream stage 2110 on which the electronic component Q to be inspected is placed and transported in the Y-axis direction, and the inspected electronic component Q is placed and transported in the Y-axis direction. A downstream stage 2120 and an inspection table 2130 that is located between the upstream stage 2110 and the downstream stage 2120 and inspects the electrical characteristics of the electronic component Q are provided. Examples of the electronic component Q include semiconductors, semiconductor wafers, display devices such as CLD and OLED, crystal devices, various sensors, ink jet heads, various MEMS devices, and the like.

  The support table 2200 is provided with a Y stage 2210 that can move in the Y-axis direction with respect to the support table 2200, and the Y stage 2210 can move in the X-axis direction with respect to the Y stage 2210. A stage 2220 is provided. The X stage 2220 is provided with an electronic component holder 2230 that can move in the Z-axis direction with respect to the X stage 2220.

  The electronic component holding unit 2230 has a holding unit 2233 that can move in the X-axis direction and the Y-axis direction and can rotate about the Z-axis, and holds the electronic component Q. The electronic component holding unit 2230 is provided with the piezoelectric driving device 100, and the holding unit 2233 is moved in the X-axis direction and the Y-axis direction or rotated around the Z-axis by the driving force of the piezoelectric driving device 100. Or move. Instead of the piezoelectric driving device 100, a piezoelectric driving device 100A may be used.

  The electronic component conveying device 2000 as described above includes the piezoelectric driving device 100. According to such an electronic component transport device 2000, the driving force of the piezoelectric actuator 1 can be increased, and the control accuracy of the piezoelectric actuator 1 can be increased. Therefore, the electronic component transport apparatus 2000 can be reduced in size and weight, and the control accuracy of the electronic component transport apparatus 2000 can be increased.

4). Printer FIG. 12 is a perspective view showing an embodiment of a printer of the present invention.

  A printer 3000 shown in FIG. 12 is an ink jet recording type printer. The printer 3000 includes an apparatus main body 3010 and a printing mechanism 3020, a paper feed mechanism 3030, and a control unit 3040 provided inside the apparatus main body 3010.

  The apparatus main body 3010 is provided with a tray 3011 for installing the recording paper P, a paper discharge port 3012 for discharging the recording paper P, and an operation panel 3013 such as a liquid crystal display.

  The printing mechanism 3020 includes a head unit 3021, a carriage motor 3022, and a reciprocating mechanism 3023 that reciprocates the head unit 3021 by the driving force of the carriage motor 3022. The head unit 3021 includes a head 3021a that is an ink jet recording head, an ink cartridge 3021b that supplies ink to the head 3021a, and a carriage 3021c on which the head 3021a and the ink cartridge 3021b are mounted. The reciprocating mechanism 3023 includes a carriage guide shaft 3023b that supports the carriage 3021c so as to reciprocate, and a timing belt 3023a that moves the carriage 3021c on the carriage guide shaft 3023b by the driving force of the carriage motor 3022. Yes.

  The paper feeding mechanism 3030 includes a driven roller 3031 and a driving roller 3032 that are in pressure contact with each other, and a piezoelectric driving device 100 that is a paper feeding motor that drives the driving roller 3032. Instead of the piezoelectric driving device 100, a piezoelectric driving device 100A may be used.

  The control unit 3040 controls the printing mechanism 3020, the paper feeding mechanism 3030, and the like based on print data input from a host computer such as a personal computer.

  In such a printer 3000, the paper feed mechanism 3030 intermittently feeds the recording paper P one by one to the vicinity of the lower portion of the head unit 3021. At this time, the head unit 3021 reciprocates in a direction substantially orthogonal to the feeding direction of the recording paper P, and printing on the recording paper P is performed.

  The printer 3000 as described above includes the piezoelectric driving device 100. According to such a printer 3000, the driving force of the piezoelectric actuator 1 can be increased, and the control accuracy of the piezoelectric actuator 1 can be increased. Therefore, the printer 3000 can be reduced in size and weight, and the control accuracy of the printer 3000 can be increased.

5. Projector FIG. 13 is a schematic diagram showing an embodiment of a projector of the present invention.

  A projector 4000 illustrated in FIG. 13 includes a light source 4100R that emits red light, a light source 4100G that emits green light, a light source 4100B that emits blue light, lens arrays 4200R, 4200G, and 4200B, and a transmissive liquid crystal light valve. (Light modulation section) 4300R, 4300G, 4300B, cross dichroic prism 4400, projection lens (projection section) 4500, and piezoelectric driving device 4700 are provided.

  Light emitted from the light sources 4100R, 4100G, and 4100B is incident on the liquid crystal light valves 4300R, 4300G, and 4300B via the lens arrays 4200R, 4200G, and 4200B. Each of the liquid crystal light valves 4300R, 4300G, and 4300B modulates incident light according to image information.

  The three color lights modulated by the liquid crystal light valves 4300R, 4300G, and 4300B are incident on the cross dichroic prism 4400 and synthesized. The light synthesized by the cross dichroic prism 4400 enters a projection lens 4500 that is a projection optical system. The projection lens 4500 enlarges an image formed by the liquid crystal light valves 4300R, 4300G, and 4300B and projects the enlarged image onto a screen (display surface) 4600. Thus, a desired image is displayed on the screen 4600. Here, the projection lens 4500 is supported by a piezoelectric driving device 4700 which is the piezoelectric driving device 100, and the position and orientation can be changed (positioning) by driving the piezoelectric driving device 4700. Thereby, the shape and size of the image projected on the screen 4600 can be adjusted.

  In the above-described example, a transmissive liquid crystal light valve is used as the light modulation unit, but a light valve other than liquid crystal may be used, or a reflective light valve may be used. Examples of such a light valve include a reflective liquid crystal light valve and a digital micromirror device. Further, the configuration of the projection optical system is appropriately changed depending on the type of light valve used. Further, the projector may be a scanning projector that displays an image of a desired size on the display surface by scanning light on a screen.

  The projector 4000 as described above includes the piezoelectric driving device 100. According to such a projector 4000, the driving force of the piezoelectric actuator 1 can be increased, and the control accuracy of the piezoelectric actuator 1 can be increased. Therefore, the projector 4000 can be reduced in size and weight, and the control accuracy of the projector 4000 can be increased.

  The piezoelectric drive device, the piezoelectric actuator control method, the robot, the electronic component transport device, the printer, and the projector according to the present invention have been described based on the illustrated embodiments. However, the present invention is not limited to this. The configuration of each unit can be replaced with any configuration having the same function. In addition, any other component may be added to the present invention. Moreover, you may combine each embodiment suitably.

  In the above-described embodiment, the configuration in which the piezoelectric driving device is applied to a piezoelectric motor, a robot, an electronic component conveying device, a printer, and a projector has been described. However, the piezoelectric actuator can also be applied to various other electronic devices. .

DESCRIPTION OF SYMBOLS 1 ... Piezoelectric actuator, 2 ... 1st diaphragm, 3 ... 2nd diaphragm, 4 ... Piezoelectric element, 4a ... Piezoelectric element, 4b ... Piezoelectric element, 4d ... Piezoelectric element, 4d ... Piezoelectric element, 4e ... Piezoelectric element, 5 ... Intermediate member, 7 ... Wiring layer, 8 ... Wiring layer, 10 ... Control device, 10A ... Control device, 11 ... Vibration part, 12 ... Supporting part, 13 ... Connection part, 14 ... Transmission part, 24 ... Insulating layer, 34 ... Insulating layer, 41 ... Piezoelectric body, 42 ... First electrode, 42a ... First electrode, 42b ... First electrode, 42c ... First electrode, 42d ... First electrode, 42e ... First electrode, 43 ... Second electrode , 51 ... body, 52 ... insulating layer, 53 ... wiring, 61 ... adhesive, 62 ... adhesive, 71 ... first electrode, 72 ... first wiring, 81 ... second electrode, 82 ... second wiring, 91 ... Terminals 92... Terminals 100. Piezoelectric driving devices 100 A. A ... drive circuit, 101a ... first drive circuit, 101b ... second drive circuit, 101c ... third drive circuit, 102 ... detection circuit, 102A ... detection circuit, 102a ... first detection circuit, 102b ... second detection circuit, 102c ... third detection circuit, 103 ... switch, 103A ... switch, 103a ... first switch, 103b ... second switch, 103c ... third switch, 104 ... control unit, 105 ... switch, 105a ... first switch, 105b ... 2nd switch, 105c ... 3rd switch, 110 ... rotor, 111 ... outer peripheral surface, 1000 ... robot, 1010 ... base, 1020 ... arm, 1030 ... arm, 1040 ... arm, 1050 ... arm, 1060 ... arm, 1070 ... arm 1080 ... Control unit, 1090 ... End effector, 2000 ... Electronic component conveyor 2100: Base, 2110: Upstream stage, 2120: Downstream stage, 2130 ... Inspection table, 2200 ... Supporting table, 2210 ... Y stage, 2220 ... X stage, 2230 ... Electronic component holding unit, 2233 ... Holding unit, DESCRIPTION OF SYMBOLS 3000 ... Printer, 3010 ... Device main body, 3011 ... Tray, 3012 ... Paper discharge port, 3013 ... Operation panel, 3020 ... Printing mechanism, 3021 ... Head unit, 3021a ... Head, 3021b ... Ink cartridge, 3021c ... Carriage, 3022 ... Carriage Motor, 3023 ... reciprocating mechanism, 3023a ... timing belt, 3023b ... carriage guide shaft, 3030 ... paper feed mechanism, 3031 ... driven roller, 3032 ... driving roller, 3040 ... control unit, 4000 ... projector, 4100B ... light source, 410 0G ... light source, 4100R ... light source, 4200B ... lens array, 4200G ... lens array, 4200R ... lens array, 4300B ... liquid crystal light valve, 4300G ... liquid crystal light valve, 4300R ... liquid crystal light valve, 4400 ... cross dichroic prism, 4500 ... projection Lens, 4600, screen, 4700, piezoelectric drive device, O, rotating shaft, P, recording paper, Q, electronic component, α, direction, β, direction

Claims (15)

A piezoelectric actuator having a vibration part including a piezoelectric element provided with a drive electrode;
A drive circuit for generating a drive signal input to the drive electrode;
And a detection circuit that detects vibration of the vibration unit based on a detection signal output from the drive electrode. The piezoelectric element has a first piezoelectric element that flexurally vibrates the vibration part to one side, and a second piezoelectric element that flexibly vibrates the vibration part to the other side,
2. The piezoelectric drive device according to claim 1, wherein the drive electrode includes a first drive electrode provided on the first piezoelectric element and a second drive electrode provided on the second piezoelectric element. The piezoelectric element is switched between a first state in which a drive signal is input to the first drive electrode and a second state in which a drive signal is input to the second drive electrode,
The detection circuit detects vibration of the vibration unit based on a detection signal output from the second drive electrode when in the first state, and from the first drive electrode when in the second state. The piezoelectric drive device according to claim 2, wherein the vibration of the vibration unit is detected based on the output detection signal.   The drive circuit includes: a first drive circuit that generates a drive signal input to the first drive electrode; and a second drive circuit that generates a drive signal input to the second drive electrode. A piezoelectric drive device according to claim 1. A first switch provided between the first drive electrode and the first drive circuit;
A second switch provided between the second drive electrode and the second drive circuit,
When the first switch is conductive, the second switch is turned off,
The piezoelectric drive device according to claim 4, wherein when the first switch is in a cut-off state, the second switch is turned on.   The detection circuit detects a vibration of the vibration unit based on a detection signal output from the first drive electrode, and the vibration unit based on a detection signal output from the second drive electrode. The piezoelectric drive device according to claim 2, further comprising a second detection circuit that detects vibrations of the piezoelectric drive device. The switch is provided between the drive electrode and the drive circuit, and has a switch that periodically switches between a conduction state and a cutoff state alternately,
3. The piezoelectric drive device according to claim 1, wherein the detection circuit detects vibration of the vibration unit based on the detection signal in the cut-off state. 4.   3. The piezoelectric drive device according to claim 1, wherein the detection circuit generates a correction signal obtained by removing a component corresponding to the drive signal from the detection signal, and detects vibration of the vibration unit based on the correction signal. . A method for controlling a piezoelectric actuator having a vibration part including a piezoelectric element provided with a drive electrode,
A drive signal is input to the drive electrode to drive the piezoelectric element;
A method for controlling a piezoelectric actuator, comprising detecting vibration of the vibration unit based on a detection signal output from the drive electrode. A first period in which the drive signal is input to the drive electrode and a second period in which the drive signal is not input are alternately and periodically repeated,
The method for controlling a piezoelectric actuator according to claim 9, wherein vibration of the vibration unit is detected based on the detection signal in the second period.   The method for controlling a piezoelectric actuator according to claim 9, wherein the vibration of the vibration unit is detected based on the detection signal in a state where the drive signal is input to the drive electrode.   A robot comprising the piezoelectric drive device according to claim 1.   An electronic component conveying device comprising the piezoelectric driving device according to claim 1.   A printer comprising the piezoelectric drive device according to claim 1.   A projector comprising the piezoelectric driving device according to claim 1.

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