TWI611655B - Drive device, drive circuit, robot arm, robot, electronic component transport device, electronic component inspection device - Google Patents

Abstract

In the present invention, a pulse voltage waveform in which the first voltage and the second voltage are repeated in a predetermined cycle is applied to the vibrating body of the piezoelectric motor via the LC circuit portion. Further, the voltage waveform repeats the first voltage and the second voltage in a period shorter than the resonance period of the vibrating body, and the modulation component of the resonance frequency of the vibrating body is modulated by the pulse width. In this case, the voltage of the component of the resonance frequency is amplified by resonance, and the fluctuation of the voltage of the other frequency components is suppressed. As a result, even when the ambient temperature changes, the voltage does not easily fluctuate due to the influence of components other than the resonance frequency. Therefore, voltage management is facilitated, and the object can be accurately positioned at a desired position.

Description

Drive device, drive circuit, robot arm, robot, electronic component transport device, electronic component inspection device

The present invention relates to a driving device, a driving circuit, a robot arm, a robot, an electronic component conveying device, and an electronic component inspection device.

A piezoelectric motor that vibrates a vibrating body formed of a piezoelectric material to drive an object is known. In the piezoelectric motor, the vibrating body is vibrated by applying a driving voltage of a predetermined period to the vibrating body, and the object is driven by the convex portion provided on the end surface of the vibrating body.

Here, since the displacement of the piezoelectric material is proportional to the applied voltage, in order to greatly vibrate the vibrating body, it is necessary to increase the amplitude of the driving voltage. Therefore, it is necessary to generate a high-voltage power source. Therefore, there is a method in which the vibrating body is largely vibrated by resonance by applying a driving voltage of a resonance period of the vibrating body, whereby the object can be driven at a faster speed.

In addition, in order to greatly vibrate the vibrating body by resonance, and to change the driving speed of the object, a technique is also known in which a pulse-shaped driving voltage is applied to the resonance period of the vibrating body, and the pulse width of the driving voltage can be changed (patent Document 1).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2011-5402

However, in the technique proposed above, there is a problem that it is difficult to precisely position an object. That is, there is a problem in that when the object is to be slightly moved, it is excessively moved or reversely moved to be removed and it is difficult to locate to a desired position.

The present invention has been made in order to solve the above-described problems of the prior art, and an object of the present invention is to provide a technique for accurately positioning a target by accurately vibrating a vibrating body of a piezoelectric motor by resonance.

In order to solve at least a part of the above problems, the drive device of the present invention adopts the following configuration. That is, a driving device includes: a vibrating body formed of a piezoelectric material and having a convex portion pressed against the object; and a voltage waveform output portion whose output repeats the first voltage and is higher than the above a voltage waveform of a second voltage of the voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and including a coil and a capacitor; wherein the driving device is configured to: The period in which the resonance period of the vibrating body is shorter is repeated. The voltage waveform of the first voltage and the second voltage and the modulation component of the resonant frequency of the vibrating body is modulated by the pulse width.

In the driving device of the present invention, the voltage waveform of the first voltage and the second voltage is repeated for a predetermined period of time to be applied to the vibrating body via the LC circuit portion. Further, the voltage waveform is a voltage waveform in which the first voltage and the second voltage are repeated in a period shorter than the resonance period of the vibrating body, and the modulation component of the resonance frequency of the vibrating body is modulated by the pulse width. Further, the modulation component does not need to be only a component of the resonance frequency of the vibrating body, and may contain a large number of frequency components in addition to the component of the resonance frequency of the vibrating body.

According to this, for the resonant frequency of the vibrating body in the pulse-modulated voltage waveform Since the component is amplified by the resonance and applied to the vibrating body by the resonance, the vibrating body can be largely vibrated to drive the object without using a power source or the like that generates a high voltage. On the other hand, a frequency component other than the resonance frequency (repetition of the first voltage and the second voltage component in a period shorter than the resonance frequency) is applied to the vibrating body in a state where the fluctuation of the voltage is suppressed. The detailed mechanism will be described below. However, if there is a large fluctuation component at a frequency other than the resonance frequency of the vibrating body, the voltage applied to the vibrating body greatly changes when the ambient temperature fluctuates. And the situation of not changing, making the management of voltage difficult. In this regard, in the driving device of the present invention, since the voltage waveform in which the frequency component other than the resonance frequency is suppressed can be applied to the vibrating body, the object can be accurately positioned at a desired position.

Further, in the driving device of the present invention, the voltage waveform output unit may generate a voltage waveform by amplifying a voltage between the first voltage and the second voltage, and output the voltage waveform to the LC circuit unit.

When the pulse signal is voltage-amplified, a simple circuit can be used, and a voltage waveform in which the voltage is switched between the first voltage and the second voltage is generated without a large power loss (thus, a large heat dissipation mechanism is not required). As a result, the drive device can be miniaturized.

Further, in the above-described driving device of the present invention, a voltage waveform obtained by pulsing a sine wave having a resonance frequency of a vibrating body as a modulation component may be used as a voltage waveform outputted from the voltage waveform output unit to the LC circuit unit.

The sine wave contains only one frequency. Therefore, when the sine wave of the resonance frequency of the vibrating body is used as the modulation component, components other than the resonance frequency in the voltage waveform output to the LC circuit portion can be suppressed. Therefore, it is possible to suppress a situation in which the fluctuation of the voltage applied to the vibrating body when the ambient temperature fluctuates, so that the object can be accurately positioned at a desired position.

Further, in the driving device of the present invention, the voltage waveform applied to the LC circuit portion may be set to repeat the first voltage and the second voltage in a period of one seventh or less of the resonance period. The voltage waveform.

According to this, it is possible to sufficiently suppress the frequency component caused by repeating the first voltage and the second voltage due to the voltage waveform. Therefore, the state of variation of the voltage applied to the vibrating body when the ambient temperature fluctuates is suppressed, and as a result, the object can be accurately positioned at a desired position.

Moreover, the present invention can also be understood as an aspect of a driving circuit of a piezoelectric motor. The drive circuit of the present invention, which is understood to be in such a manner, is a drive circuit including a piezoelectric motor including a vibrating body formed of a piezoelectric material, and is mainly intended to include a voltage waveform output unit whose output is repeated for a first time in a certain period. a voltage waveform having a voltage higher than a second voltage higher than the first voltage; and an LC circuit portion interposed between the voltage waveform output portion and the vibrating body, including a coil and a capacitor; and the voltage waveform is higher than the above The period in which the resonance period of the vibrating body is shorter is repeated. The voltage waveform of the first voltage and the second voltage and the modulation component of the resonant frequency of the vibrating body is modulated by the pulse width.

In the driving circuit of the present invention, the voltage of the resonant frequency of the vibrating body in the pulse-modulated voltage waveform is also amplified and applied to the vibrating body by resonance, thereby vibrating the piezoelectric motor. The body applies a high voltage driving voltage. On the other hand, a frequency component other than the resonance frequency (repetition of the first voltage and the second voltage component in a period shorter than the resonance frequency) is applied to the vibrating body in a state where the fluctuation of the voltage is suppressed. The detailed mechanism will be described below. However, it is possible to prevent the voltage from being applied to the vibrating body from greatly changing when the ambient temperature fluctuates, and the management of the voltage is difficult because the voltage is not greatly changed. situation. As a result, the piezoelectric motor can be used to accurately position the object at a desired position.

Further, in the drive circuit of the present invention, the voltage waveform output unit may generate a voltage waveform by amplifying a voltage between the first voltage and the second voltage, and output the voltage waveform. To the LC circuit department.

According to this, a simple circuit can be used, and a voltage waveform in which a voltage is switched between the first voltage and the second voltage is generated without a large power loss (thus, a large heat dissipation mechanism is not required).

Further, in the drive circuit of the present invention, a voltage waveform obtained by pulsing a sine wave having a resonance frequency of a vibrating body as a modulation component may be used as a voltage waveform outputted from the voltage waveform output unit to the LC circuit unit.

According to this, it is possible to suppress a component other than the resonance frequency of the voltage waveform input to the LC circuit portion. Therefore, it is possible to suppress a situation in which the fluctuation of the voltage applied to the vibrating body when the ambient temperature fluctuates. As a result, the piezoelectric motor can be used to accurately position the object at a desired position.

Further, in the drive circuit of the present invention, the voltage waveform applied to the LC circuit portion may be a voltage waveform in which the first voltage and the second voltage are repeated in a period of one seventh or less of the resonance period.

According to this, it is possible to sufficiently suppress the frequency component caused by the repetition of the first voltage and the second voltage due to the voltage waveform. Therefore, the fluctuation of the voltage applied to the vibrating body when the ambient temperature fluctuates is suppressed, and as a result, The object is accurately positioned at the desired position.

Moreover, the present invention can also be understood in the following manner of the robot arm. That is, it can also be understood as a robotic arm that includes a plurality of fingers and holds the object, and is characterized in that it comprises: a base body on which the movable finger portion is erected; and a driving device. Moving the finger portion relative to the base body; and the driving device includes: a vibrating body formed of a piezoelectric material and having a convex portion pressed against the object; a voltage waveform output unit that outputs a voltage waveform in which the first voltage and the second voltage higher than the first voltage are repeated in a predetermined cycle; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and And including the coil and the capacitor; wherein the voltage waveform is a voltage that is modulated by a pulse width modulation of the first voltage and the second voltage in a period shorter than a resonance period of the vibrating body, and a modulation component of a resonant frequency of the vibrating body Waveform.

According to the present invention, it is possible to realize a robot arm that can be accurately positioned.

Further, in the robot arm of the present invention, the voltage waveform output unit may generate a voltage waveform by amplifying a voltage between the first voltage and the second voltage, and output the voltage waveform to the LC circuit unit.

According to this, a simple circuit can be used, and a voltage waveform in which a voltage is switched between the first voltage and the second voltage is generated without a large power loss (thus, a large heat dissipation mechanism is not required).

Further, in the robot arm of the present invention, a voltage waveform obtained by pulsing a sine wave having a resonance frequency of a vibrating body as a modulation component may be used as a voltage waveform outputted from the voltage waveform output unit to the LC circuit unit.

According to this, it is possible to suppress a component other than the resonance frequency of the voltage waveform input to the LC circuit portion. Therefore, it is possible to suppress a situation in which the fluctuation of the voltage applied to the vibrating body when the ambient temperature fluctuates. As a result, the piezoelectric motor can be used to accurately position the object at a desired position.

Further, in the robot arm of the present invention, the voltage waveform applied to the LC circuit portion may be a voltage waveform in which the first voltage and the second voltage are repeated in a period of one seventh or less of the resonance period.

According to this, it is possible to sufficiently suppress the frequency component caused by repeating the first voltage and the second voltage due to the voltage waveform, and therefore, the voltage applied to the vibrating body when the ambient temperature fluctuates The state of the dynamic deviation is suppressed, and as a result, the object can be accurately positioned at a desired position.

Moreover, the present invention can also be understood in the following aspects of the robot. That is, it can also be understood as a robot comprising: a wrist portion provided with a rotatable joint portion; a hand portion disposed on the wrist portion; and a body portion provided with the wrist portion; the robot The invention includes a driving device that is disposed on the joint portion and that drives or rotates the joint portion, and the driving device includes a vibrating body that is formed of a piezoelectric material and has a convex portion pressed against the object. a voltage waveform output unit that outputs a voltage waveform in which the first voltage and the second voltage higher than the first voltage are repeated in a predetermined cycle; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body; And including the coil and the capacitor; and the voltage waveform repeats the first voltage and the second voltage in a period shorter than a resonance period of the vibrating body, and the modulation component of the resonant frequency of the vibrating body is modulated by a pulse width Voltage waveform.

According to the present invention, it is possible to realize a robot that can be accurately positioned.

Further, in the robot of the present invention, the voltage waveform output unit may generate a voltage waveform by amplifying a voltage between the first voltage and the second voltage, and output the voltage waveform to the LC circuit unit.

According to this, a simple circuit can be used, and a voltage waveform in which a voltage is switched between the first voltage and the second voltage is generated without a large power loss (thus, a large heat dissipation mechanism is not required).

Moreover, the present invention can also be understood in the following aspects of the electronic component transport apparatus. That is, it can be understood as an electronic component conveying device including: a grip portion that holds an electronic component; and a driving device that drives the grip portion that holds the electronic component; the electron The component transporting apparatus is characterized in that the driving device includes a vibrating body formed of a piezoelectric material and having a convex portion pressed against the grip portion, and a voltage waveform output portion whose output repeats at a predetermined period. a voltage waveform having a voltage higher than a second voltage higher than the first voltage; and an LC circuit portion interposed between the voltage waveform output portion and the vibrating body, including a coil and a capacitor; and the voltage waveform is higher than the above The period in which the resonance period of the vibrating body is shorter is repeated. The voltage waveform of the first voltage and the second voltage and the modulation component of the resonant frequency of the vibrating body is modulated by the pulse width.

According to the present invention, it is possible to realize an electronic component conveying apparatus capable of accurately positioning an electronic component.

Moreover, the present invention can also be understood in the following aspects of the electronic component inspection apparatus. That is, it can also be understood as an electronic component inspection apparatus including: a grip portion that holds an electronic component; a driving device that drives the grip portion that holds the electronic component; and an inspection portion , which inspects the above electronic components; the electronic component inspection device is characterized by The driving device includes: a vibrating body formed of a piezoelectric material and having a convex portion pressed against the grip portion; and a voltage waveform output portion whose output repeats the first voltage and is higher than the above a voltage waveform of a second voltage of the first voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and including a coil and a capacitor; and the voltage waveform is a resonance period of the vibrating body The voltage waveform in which the first voltage and the second voltage are repeated and the modulation component of the resonant frequency of the vibrating body is modulated by the pulse width is repeated in a shorter period.

According to the present invention, an electronic component inspection device capable of accurately positioning an electronic component can be realized.

Further, the present invention can also be understood in the following aspects of the liquid feeding pump. That is, it can also be understood as a liquid feeding pump comprising: a liquid tube for allowing the liquid to flow; a blocking portion abutting against a portion of the liquid tube to block the liquid tube; and a moving portion Moving the state of the clogging portion to move the clogging position of the liquid pipe; and driving means for driving the moving portion; the liquid feeding pump is characterized in that the driving device includes a vibrating body including a pressure Forming an electric material and having a convex portion pressed against the moving portion; and a voltage waveform output portion outputting a voltage waveform in which the first voltage and the second voltage higher than the first voltage are repeated in a predetermined cycle; and the LC circuit portion Between the voltage waveform output portion and the vibrating body, and And including the coil and the capacitor; wherein the voltage waveform is a voltage that is modulated by a pulse width modulation of the first voltage and the second voltage in a period shorter than a resonance period of the vibrating body, and a modulation component of a resonant frequency of the vibrating body Waveform.

According to the present invention, it is possible to realize a liquid feeding pump that can accurately feed the liquid by accurately positioning the moving portion.

Further, the present invention can also be understood in the following aspects of the printing apparatus. That is, it can also be understood as a printing device comprising: a printing head that prints an image on the medium; and a driving device that moves the printing head; the printing device is characterized in that the driving device The invention includes a vibrating body formed of a piezoelectric material and having a convex portion pressed against the print head, and a voltage waveform output portion whose output repeats the first voltage and the first voltage higher than the first voltage. a voltage waveform of the voltage; and an LC circuit portion interposed between the voltage waveform output portion and the vibrating body, and including a coil and a capacitor; and the voltage waveform is repeated in a cycle shorter than a resonance period of the vibrating body a voltage waveform in which the first voltage and the second voltage and the modulation component of the resonant frequency of the vibrating body are modulated by a pulse width.

According to the present invention, it is possible to realize a printing apparatus capable of printing a high-quality image by accurately positioning the printing head.

Moreover, the present invention can also be understood in the form of an electronic clock as follows. That is, it can also be understood as an electronic clock comprising: a rotating circular plate which is coaxially arranged with a gear and can be rotated; and a gear train comprising a plurality of gears; a pointer connected to the gear train and indicating a time; and a driving device that drives the rotating circular plate; the electronic clock is characterized in that: the driving device includes: a vibrating body formed of a piezoelectric material, and having Pressing the convex portion of the rotating circular plate; the voltage waveform output portion outputs a voltage waveform in which the first voltage and the second voltage higher than the first voltage are repeated in a predetermined cycle; and the LC circuit portion is interposed between the voltages The waveform output unit and the vibrating body include a coil and a capacitor; and the voltage waveform repeats the first voltage and the second voltage and the resonance of the vibrating body in a period shorter than a resonance period of the vibrating body The frequency modulation component of the frequency modulation component is modulated by the pulse width.

According to the present invention, an electronic clock having high precision can be realized by accurately positioning the rotating circular plate.

Moreover, the present invention can also be understood in the following aspects of the projection apparatus. That is, it can also be understood as a projection apparatus including: a projection unit including an optical lens and projecting light from the light source; an adjustment unit that adjusts a projection state of the light using the optical lens; and a driving device The projection device is characterized in that the driving device includes a vibrating body formed of a piezoelectric material and having a convex portion pressed against the adjusting portion, and a voltage waveform output portion outputting a voltage waveform in which the first voltage and the second voltage higher than the first voltage are repeated in a predetermined cycle; and the LC circuit unit is interposed between the voltage waveform output unit and the vibrating body, and includes a coil and a capacitor; The voltage waveform is a voltage waveform in which the first voltage and the second voltage are repeated in a period shorter than a resonance period of the vibrating body, and a modulation component of a resonance frequency of the vibrating body is pulse width modulated.

According to the present invention, it is possible to realize a projection apparatus capable of accurately adjusting the projection state by accurately positioning the adjustment unit.

1‧‧‧ Piezoelectric motor

1c‧‧‧ Piezoelectric motor

1m‧‧‧piezoelectric motor

1s‧‧‧ Piezoelectric motor

Piezoelectric motor for 1x‧‧‧X direction

1y‧‧‧ Piezoelectric motor for Y direction

1θ‧‧‧ Piezoelectric motor for rotation

2‧‧‧Printing media

2fp‧‧‧frequency component of pulse signal A

3‧‧‧Electronic parts

Frequency component of 3fp‧‧‧pulse signal A

10‧‧‧ Body Department

20‧‧‧Outer casing

30‧‧‧Vibration Department

32‧‧‧ vibrating body

34‧‧‧Drive convex

36‧‧‧ positive electrode

36a‧‧‧ positive electrode

36b‧‧‧ positive electrode

36c‧‧‧ positive electrode

36d‧‧‧ positive electrode

40‧‧‧Vibration body shell

110‧‧‧Drive voltage generation circuit

114‧‧‧Drive convex

120‧‧‧Full Bridge Circuit Department

140‧‧‧LC Circuit Department

600‧‧‧Machine arm

601‧‧ Tools

602‧‧‧Abutment

603‧‧‧ finger

604‧‧‧ wrist

610‧‧‧ Arm

612‧‧‧Links

620‧‧‧ Joint Department

650‧‧‧Robot

660‧‧‧Robot

662‧‧‧ head

663‧‧‧ camera

664‧‧‧ Body Department

666‧‧‧Control Department

668‧‧‧ casters

700‧‧‧Electronic parts inspection device

710‧‧‧Abutment

712d‧‧‧ downstream side stage

712u‧‧‧Upstream side mounting table

714‧‧‧ camera

716‧‧‧Checkpoint

718‧‧‧Control device

730‧‧‧Support table

732‧‧‧Y mounting platform

734‧‧‧ wrist

736‧‧‧X mounting table

738‧‧‧ camera camera

750‧‧‧ holding device

752‧‧‧ grip

754‧‧‧Rotary axis

756‧‧‧ micro adjustment plate

800‧‧‧ liquid pump

802‧‧‧shell

804‧‧‧Rotor

806‧‧‧ tube

808‧‧ balls

850‧‧‧Printing device

851‧‧‧Tray tray

852‧‧‧Export

853‧‧‧paper holder

854‧‧‧ Roller paper

855‧‧‧ operation button

860‧‧‧rails

870‧‧‧Print head

872‧‧‧Printing Department

874‧‧‧Scanning Department

880‧‧‧cutting mechanism

882‧‧‧Guide axis

884‧‧‧Cutter Holder

886‧‧‧Use paper cutter

900‧‧‧Electronic clock

902‧‧‧Rotating circular plate

902g‧‧‧ gear

904‧‧‧ Gear train

906‧‧‧Power Supply Department

908‧‧‧Crystal Wafer

910‧‧‧IC

950‧‧‧Projection device

952‧‧‧Projection Department

954‧‧‧Adjustment agency

956‧‧‧ lens cover

A‧‧‧ pulse signal

B‧‧‧ Sine wave

C‧‧‧ capacitor

C‧‧‧ modulated pulse signal

D‧‧‧汲

Fo‧‧‧resonance frequency

Frequency component of fp‧‧‧pulse signal A

G‧‧‧ gate

G1‧‧‧ Gain

G2‧‧‧ Gain

G3‧‧‧ Gain

PVDD‧‧‧Power supply voltage

PVSS‧‧‧Power supply voltage

S‧‧‧ source

SW1‧‧‧ switch

SW2‧‧‧ switch

T‧‧‧temperature

To‧‧ cycle

Tp‧‧ cycle

TP1‧‧‧ position

TP2‧‧‧ position

TP3‧‧‧ position

TP4‧‧‧ position

TP5‧‧‧ position

TR1‧‧‧O crystal

TR2‧‧‧O crystal

TR3‧‧‧O crystal

TR4‧‧‧O crystal

X‧‧‧ direction

Y‧‧‧ direction

Z‧‧‧ direction

Θ‧‧‧ direction

1(a) to 1(c) are explanatory views showing the configuration of a piezoelectric motor used in the driving device of the present embodiment.

2(a) and 2(b) are explanatory views showing the principle of operation of the piezoelectric motor.

Fig. 3 is a block diagram showing a driving voltage generating circuit for generating a driving voltage by the driving device of the embodiment.

4(a) and 4(b) are explanatory views showing the operation of the full-bridge circuit unit in the drive voltage generating circuit.

Fig. 5 is an explanatory view showing a change in voltage appearing on the output side of the full-bridge circuit portion.

Fig. 6 is an explanatory view showing the gain characteristics of the full bridge circuit portion.

Fig. 7 is an explanatory view showing the relationship between the high-frequency harmonics included in the pulse waveform and the gain characteristics.

(a) and (b) of FIG. 8 are explanatory views showing the reason why it is difficult to manage the driving amount with respect to the change in the ambient temperature in the conventional method of driving the piezoelectric motor.

Figs. 9(a) and 9(b) are explanatory diagrams showing a pulse signal input to the full-bridge circuit unit by the driving method of the piezoelectric motor of the embodiment.

Fig. 10 is an explanatory view showing the relationship between the signal component and the gain characteristic of the pulse signal of the present embodiment.

(a) and (b) of FIG. 11 are explanatory views showing the reason why the management of the driving amount with respect to the change in the ambient temperature is easy in the driving method of the present embodiment.

Fig. 12 (a) and (b) are explanatory views showing changes in gain with respect to temperature change.

FIGS. 13(a) to 13(c) are explanatory diagrams illustrating modulation components used to generate a modulation pulse signal by a driving method of a variation.

Fig. 14 is an explanatory view showing a robot arm in which a piezoelectric motor is incorporated.

Fig. 15 is an explanatory view showing a one-arm robot equipped with a robot arm.

Fig. 16 is an explanatory view showing a multi-arm robot equipped with a robot arm.

Fig. 17 is a perspective view showing an electronic component inspection device constructed by incorporating a piezoelectric motor.

Fig. 18 is an explanatory view of a fine adjustment mechanism built in the holding device.

19(a) and 19(b) are explanatory views showing a liquid supply pump incorporating a piezoelectric motor.

Fig. 20 is a perspective view showing a printing apparatus incorporating a piezoelectric motor.

Fig. 21 is an explanatory view showing an electronic clock incorporating a piezoelectric motor.

Fig. 22 is a perspective view showing a projection apparatus incorporating a piezoelectric motor.

A. The composition of the piezoelectric motor:

Fig. 1 is an explanatory view showing the configuration of the piezoelectric motor 1 of the present embodiment. An overall view of the piezoelectric motor 1 of the present embodiment is shown in Fig. 1(a). The piezoelectric motor 1 of the present embodiment substantially includes a main body portion 10, an outer casing 20, and the like which are indicated by oblique lines in the drawing. The main body portion 10 is incorporated into the outer casing 20 in a state of being pressed in one direction by a spring (not shown). Further, as shown in FIG. 1(b), the main body portion 10 includes a vibrating portion 30 indicated by a hatched line in the drawing, a vibrating body case 40 in which the vibrating portion 30 is housed, and the like. The vibrating portion 30 is held in the vibrating body case 40 while being allowed to vibrate.

The appearance of the vibrating portion 30 is shown in Fig. 1(c). The vibrating portion 30 includes a vibrating body 32 formed of a piezoelectric material and having a rectangular parallelepiped shape, a ceramic driving convex portion 34 attached to an end surface of the vibrating body 32 in the longitudinal direction, and a side surface of the vibrating body 32 divided into four portions. The four positive electrodes 36 (36a, 36b, 36c, 36d) and the like are provided. Further, a back electrode (not shown) is provided on a side surface opposite to the side on which the positive electrode 36 is provided. Furthermore, Yu Ben said In the specification, the longitudinal direction of the vibrating body 32 is referred to as the X direction, and the direction orthogonal to the X direction is referred to as the Y direction (see FIG. 1(c)).

B. The operating principle of the piezoelectric motor:

FIG. 2 is an explanatory view showing the principle of operation of the piezoelectric motor 1. The piezoelectric motor 1 operates by alternately applying positive and negative voltages to the positive electrode 36 of the vibrating portion 30. For example, as shown in the diagram on the left side of Fig. 2(a), when a positive voltage is applied to the positive electrode 36a and the positive electrode 36d of the vibrating body 32, a portion to which a positive voltage is applied is expanded, and the vibrating body 32 is bent as shown. At this time, bending and expansion are simultaneously generated in the vibrating body 32. Therefore, the end portion (the portion in which the driving convex portion 34 is mounted) in the longitudinal direction (X direction) of the vibrating body 32 is drawn on the drawing to describe the arc of the ellipse. Move to the upper right.

On the other hand, as shown in the right side view of Fig. 2(a), when a negative voltage is applied to the positive electrode 36a and the positive electrode 36d, the portion to which the negative voltage is applied contracts, and the vibrating body 32 is bent as shown. At this time, since the vibrating body 32 simultaneously bends and contracts, the front end portion of the vibrating body 32 moves in the lower left direction so as to draw an elliptical arc in the drawing. Therefore, when the positive and negative voltages are alternately applied to the positive electrode 36a and the positive electrode 36d, the front end portion (the driving convex portion 34) of the vibrating body 32 starts elliptical motion in the clockwise direction. Therefore, when the positive electrode 36a and the positive electrode 36d are alternately applied with positive and negative voltages in a state where the front end portion (the driving convex portion 34) of the vibrating body 32 is pressed against the object, the driving convex portion 34 of the vibrating body 32 is The aspect shown in Fig. 2(a) is subjected to an elliptical motion so that the object is driven in the Y (+) direction by the frictional force received from the driving convex portion 34.

Further, as shown in FIG. 2(b), when a positive voltage or a negative voltage is applied to the positive electrode 36b and the positive electrode 36c, the vibrating body 32 is bent in the opposite direction with respect to the case of FIG. 2(a). Therefore, the front end portion of the vibrating body 32 moves in the manner of drawing an ellipse in the opposite direction with respect to the case of Fig. 2(a). Therefore, when positive and negative voltages are alternately applied to the positive electrode 36b and the positive electrode 36c in a state where the front end portion (the driving convex portion 34) of the vibrating body 32 is pressed against the object, the driving convex portion 34 of the vibrating body 32 is illustrated. The aspect shown in 2(b) performs an elliptical motion, thereby The elephant is driven in the Y (-) direction by the frictional force received from the driving convex portion 34. Moreover, the voltage (driving voltage) applied to the vibrating body 32 when the object is driven in this manner is generated using the following circuit.

C. Piezoelectric motor driving voltage generation circuit:

FIG. 3 is an explanatory diagram showing a circuit (driving voltage generating circuit 110) used to generate a driving voltage. Further, the driving voltage generating circuit 110 and the piezoelectric motor 1 (the vibrating body 32 in FIG. 3) to which the driving voltage from the driving voltage generating circuit 110 is applied correspond to the "driving device" in the present invention. The driving voltage generating circuit 110 includes a full-bridge circuit unit 120 that amplifies the pulse signal power, an LC circuit unit 140 that is connected to the output side of the full-bridge circuit unit 120, and the like. The full-bridge circuit unit 120 includes four transistors (TR1, TR2, TR3, and TR4), and generates a pulse-like voltage waveform that is amplified to the level of the power supply voltages PVDD and PVSS by the switching of the transistor. The generated voltage waveform is applied to the vibrating body 32 via the LC circuit portion 140. Further, a switch SW1 and a switch SW2 are interposed between the LC circuit unit 140 and the vibrating body 32, and the driving direction of the object can be switched by turning any of the switches ON. In the present embodiment, when the switch SW1 is turned on, it is driven in the Y (+) direction, and when the switch SW2 is turned on, it is driven in the Y (-) direction.

Furthermore, in the present embodiment, the power supply voltage PVSS corresponds to the "first voltage" in the present invention, and the power supply voltage PVDD corresponds to the "second voltage" in the present invention. Further, the full bridge circuit unit 120 corresponds to the "voltage waveform output unit" in the present invention.

FIG. 4 is an explanatory view showing the operation of the full bridge circuit unit 120. FIG. 4(a) shows an operation in the case where a pulse signal having a high level is input to the full bridge circuit unit 120. The pulse signal is input to the gate (G) terminal of each of the transistor TR1 and the transistor TR2. The transistor TR1 and the transistor TR2 are connected to each other by a drain (D) terminal. Further, the source (S) terminal of the transistor TR1 is connected to the power supply voltage PVDD on the high potential side, and the source (S) terminal of the transistor TR2 is connected to the power supply voltage PVSS on the low potential side. Therefore, if a high level signal is input to the gate (G) terminal, the transistor TR1 is turned on, and the transistor TR2 is turned off (OFF), thereby The potential of the power supply voltage PVDD on the high potential side appears at the position TP3 on the output side.

Similarly, the transistor TR3 and the transistor TR4 are connected to each other with a drain (D) terminal, the source (S) terminal of the transistor TR3 is connected to the power supply voltage PVDD, and the source (S) terminal of the transistor TR4 is connected to Power supply voltage PVSS. Further, the pulse signal is inverted to a low level by a NOT gate, and is input to the gate (G) terminal of the transistor TR3 and the transistor TR4. Therefore, the transistor TR3 is turned off, and the transistor TR4 is turned on, so that the potential of the power supply voltage PVSS on the low potential side appears at the position TP2 on the output side.

The operation of the case where the high-level pulse signal is input to the full-bridge circuit unit 120 has been described above. On the other hand, when a low level pulse signal is input, the full bridge circuit unit 120 operates as follows.

FIG. 4(b) shows an operation in the case where a pulse signal having a low level is input to the full bridge circuit unit 120. In this case, a low level signal is input to the gate (G) terminals of the transistor TR1 and the transistor TR2. Therefore, the transistor TR1 is turned off, the transistor TR2 is turned on, and the potential of the power supply voltage PVSS on the low potential side appears at the position TP3 on the output side. Further, a signal of a high level is input to the gate (G) terminal of the transistor TR3 and the transistor TR4 via the reverse gate. Therefore, the transistor TR3 is turned on, the transistor TR4 is turned off, and the potential of the power supply voltage PVDD on the high potential side appears at the position TP2 on the output side. Thus, the above-described operations of FIGS. 4(a) and 4(b) are repeated in accordance with the level of the pulse signal input to the full bridge circuit unit 120.

Fig. 5 is an explanatory view showing a change in voltage appearing on the output side (between the position TP2 and the position TP3) when the pulse signal is input to the full bridge circuit unit 120. As described above with reference to FIG. 4, when a high-level pulse signal is input to the full-bridge circuit unit 120, the potential of the position TP2 becomes PVSS, and the potential of the position TP3 becomes PVDD. When a low-level pulse signal is input to the full-bridge circuit unit 120, the potential of the position TP2 becomes PVDD, and the potential of the position TP3 becomes PVSS. As a result, when the input of the pulse signal is switched to the high level and the low level, the voltage appearing on the output side of the full bridge circuit unit 120 (between the position TP2 and the position TP3) becomes the absolute value (PVDD-PVSS). Pulse-like voltage switching between positive and negative Waveform (refer to Figure 5). The period To of the voltage waveform corresponds to a period in which the pulse signal input to the full bridge circuit portion 120 repeats the high level and the low level. Such a voltage waveform is input to the LC circuit portion 140, and a driving voltage is applied to the vibrating body 32 from the output side of the LC circuit portion 140.

Further, when the period of the pulse signal input to the full-bridge circuit unit 120 (the period in which the high level and the low level are repeated) is changed, the magnitude of the voltage output from the LC circuit unit 140 changes. Therefore, when the frequency (=1/To) of the pulse-shaped voltage waveform input to the LC circuit unit 140 is obtained, the input voltage to the LC circuit unit 140 (the voltage between the position TP2 and the position TP3) and the output voltage (position TP4) are obtained. The gain characteristic shown in Fig. 6 can be obtained by the ratio (gain) of the voltage between the position TP5. As shown in the figure, if the frequency (=1/To) of the pulse-shaped voltage waveform input to the LC circuit unit 140 coincides with the resonance frequency fo of the LC circuit unit 140, the gain is sharply increased, and the output is greatly amplified. Voltage waveform.

Therefore, when a pulse signal corresponding to the period To (=1/fo) of the resonance frequency fo of the LC circuit portion 140 is input to the full bridge circuit portion 120, the voltage waveform repeated with the period To can be output from the full bridge circuit portion 120. And it is greatly enlarged in the LC circuit unit 140. Therefore, even if the power supply voltage of the full bridge circuit unit 120 is not increased, a higher voltage can be applied to the vibrating body 32.

Further, the vibrating body 32 itself also has a resonance frequency. Since the resonance frequency fo of the LC circuit unit 140 can be relatively freely set by selecting the inductance L of the coil or the capacitance C of the capacitor, if the resonance frequency fo of the LC circuit unit 140 is made to coincide with the resonance frequency of the vibrating body 32, Then, the vibrating body 32 can be vibrated with a larger amplitude. Therefore, the resonance frequency fo of the LC circuit unit 140 is set so as to match the resonance frequency of the vibrating body 32.

However, in the method of using a pulse signal corresponding to the period of the resonance frequency fo of the LC circuit portion 140 (method used in the past), there is a problem that it is difficult to manage the driving amount of the piezoelectric motor 1. Hereinafter, this aspect will be described.

As is well known, the pulse waveform is formed by a fundamental wave corresponding to the frequency of the period of the pulse waveform and a high frequency harmonic having a frequency which is an integral multiple of the fundamental wave. So if you are on LC When the circuit unit 140 receives a pulse-shaped voltage waveform, not only the fundamental wave is amplified, but also the high-frequency harmonics are amplified. In the gain characteristic (characteristic of the value of the gain with respect to the frequency) shown in Fig. 7, the gain corresponding to the fundamental wave is represented by a white circle, and the gain corresponding to the high frequency harmonic is represented by a black dot. Furthermore, in Fig. 7, the display is omitted for the higher frequency harmonics of the fourth higher order.

Further, the inductance L of the coil constituting the LC circuit unit 140 or the capacitance C of the capacitor changes depending on the temperature. Therefore, the resonance frequency fo of the gain characteristic shown in Fig. 7 also varies depending on the temperature. Further, as in the prior art, in the method of using the pulse signal corresponding to the period of the resonance frequency fo of the LC circuit portion 140, when the resonance frequency fo of the LC circuit portion 140 changes according to the temperature change, the gain (hence the vibration of the vibrating body 32) The amplitude) will become significantly deviated.

For example, as shown in FIG. 8(a), it is assumed that the gain characteristic is shifted to the left in the drawing in accordance with the temperature change. In this case, the gain corresponding to the frequency fo of the fundamental wave of the pulse-shaped voltage waveform is reduced from the gain represented by the circle to the gain represented by the asterisk. Further, the gain corresponding to the frequency 2fo of the high-frequency harmonics is similarly reduced from the gain indicated by the circle to the gain indicated by the asterisk. That is, both the gain of the fundamental wave and the gain of the high frequency harmonic are reduced. In addition, in FIG. 8(a), the high frequency harmonics of the third higher order are omitted, but the gain is similarly reduced for the higher order harmonics.

Further, as shown in FIG. 8(b), when the gain characteristic is shifted to the right in the drawing, the gain corresponding to the frequency fo of the fundamental wave is reduced from the gain indicated by the circle to the gain indicated by the asterisk. In contrast, the gain corresponding to the frequency 2fo of the high-frequency harmonic increases from the gain represented by the circle to the gain represented by the asterisk. That is, the gain of the high-frequency harmonic changes in a direction that attenuates the change in the gain of the fundamental wave, and therefore, the change in gain as a whole is smaller than that shown in Fig. 8(a). Further, in FIG. 8(b), the display is omitted for the higher-order harmonics of the third-order higher order, but the high-frequency harmonics are similarly changed in the direction of attenuating the change in the gain of the fundamental wave.

As described above, in the previous method using the pulse signal of the resonance frequency fo of the LC circuit portion 140, even if the amount of change in temperature is the same, a gain as a whole is generated (vibration body 32) The case where the amplitude is greatly lowered (see FIG. 8(a)) and the gain as a whole is not lowered (see FIG. 8(b)). Therefore, it becomes difficult to manage the driving amount of the piezoelectric motor 1. In view of this, in the present embodiment, a pulse signal corresponding to the period of the resonance frequency fo of the LC circuit portion 140 is not used, and the following pulse signal is used.

First, a pulse signal A having a period Tp (preferably Tp≦(To/7)) which is shorter than the period To of the resonance frequency fo of the LC circuit unit 140 is prepared, and the pulse signal A will correspond to the resonance frequency. The sine wave B of the period To of the fo is subjected to PWM (Pulse Width Modulation) modulation, and a modulated pulse signal (modulated pulse signal C) is generated. The case where the modulation pulse signal C is generated by this method is shown in Fig. 9(a). Further, in FIG. 9(b), a pulse signal corresponding to the period To of the resonance frequency fo of the LC circuit portion 140 is also referred to as a reference. In the present embodiment, after the modulated pulse signal C generated in this manner is input to the full bridge circuit portion 120, a voltage is applied to the vibrating body 32 via the LC circuit portion 140. In this way, a voltage that is greatly amplified by the LC circuit unit 140 can be generated, and even if the resonance frequency fo of the LC circuit unit 140 changes due to a temperature change, the gain as a whole (the amplitude of the vibrating body 32) does not largely vary. It is based on the following reasons.

The frequency component of the modulated pulse signal C (and thus the frequency component of the voltage waveform input to the LC circuit unit 140) includes the frequency component of the pulse signal A and the frequency component of the sine wave B. Therefore, the gain corresponding to each frequency component included in the modulated pulse signal C is shown in FIG. First, the frequency component of the sine wave B as the modulation component is greatly amplified and outputted in accordance with the gain corresponding to the resonance frequency fo of the LC circuit unit 140. Therefore, similarly to the case of the previous method (using a pulse signal corresponding to the period of the resonance frequency fo of the LC circuit unit 140), even if the power supply voltage of the full bridge circuit unit 120 is not increased, a higher voltage can be applied to Vibrating body 32.

Further, as shown in Fig. 9, since the period Tp of the pulse signal A is shorter than the period To corresponding to the resonance frequency fo of the LC circuit unit 140, the frequency components (fp, 2fp, 3fp...) of the pulse signal A become It is higher than the resonance frequency fo of the LC circuit portion 140. Especially if the period Tp When it is set shorter than 1/7 of the period To, the frequency components (fp, 2fp, 3fp...) of the pulse signal A become sufficiently higher than the resonance frequency fo of the LC circuit unit 140. Therefore, the gain corresponding to the frequencies becomes a sufficiently small value.

Therefore, for example, as shown in FIG. 11(a), when the gain characteristic is shifted to the left in the drawing due to the temperature change, the gain of the frequency fo of the sine wave B as the modulation component is from the circle. The gain is reduced to the gain of the asterisk, but the gain of the frequency of the pulse signal A (fp, 2fp, 3fp...) hardly changes. Further, as shown in FIG. 11(b), when the gain characteristic is shifted to the right in the figure, the gain of the frequency fo of the sine wave B is also reduced from the gain of the circle to the gain of the asterisk, but the pulse signal A The gains of the frequencies (fp, 2fp, 3fp...) are almost constant.

Thus, even if the resonance frequency fo of the LC circuit unit 140 changes due to temperature change, the gain of the frequency (fp, 2fp, 3fp, ...) of the pulse signal A is hardly changed, and therefore, the gain as a whole is not enhanced or weakened. Change. Therefore, unlike the case of using the previous method (using a pulse signal corresponding to the period of the resonance frequency fo of the LC circuit portion 140) as described above with reference to Fig. 8, as long as the amount of change in temperature is the same, the gain as a whole is The amount of reduction does not vary significantly.

Fig. 12 is an explanatory view showing a state in which the gain as a whole changes with respect to temperature change. In Fig. 12(a), a case where a pulse signal of the resonance frequency fo of the LC circuit portion 140 is used as before is shown as a reference. When the temperature T is changed from the reference temperature T to the temperature T + ΔT, there is a case where the gain as a whole is greatly lowered (in the case of the gain G1) and a case where the gain is not lowered (in the case of the gain G2), and thus a deviation occurs. On the other hand, as shown in FIG. 12(b), when the modulated pulse signal C generated in the present embodiment is used, the gain G3 becomes the temperature T+ΔT, and the amount of change in the gain is relative to the temperature. The relationship of the amount of change ΔT is substantially the same. Therefore, the gain can be corrected in accordance with the amount of change in temperature, and the amount of driving of the piezoelectric motor 1 can be managed to accurately position the object.

D. Change example:

In the above-described embodiment, the pulse signal of the period Tp is described by generating a modulation pulse signal C by PWM-modulating the sine wave of the period To. However, the modulation component for PWM modulation in the pulse signal is not limited to the sine wave. That is, any waveform can be used as long as the period is To and the high-frequency harmonic component is smaller than the waveform of the pulse signal whose voltage is switched by the period To. As an example of such a waveform, a waveform in which the period To repeats monotonically increasing from the minimum value to the maximum value and monotonously decreasing from the maximum value to the minimum value (for example, the triangular wave D or the graph illustrated in FIG. 13( a ) is exemplified. Saw wave E, etc. exemplified in 13(b)). Further, as exemplified in FIG. 13(c), it is also possible to set the maximum value to be constant for a certain period of time after reaching the maximum value from the minimum value, and thereafter to monotonically decrease toward the minimum value, and to maintain the minimum value for a certain period of time.

E. Application example:

The piezoelectric motor 1 driven by the above-described driving voltage generating circuit 110 of the present embodiment can be preferably incorporated into the following device.

Fig. 14 is an explanatory view showing a robot arm 600 in which the piezoelectric motor 1 of the present embodiment is incorporated. The robot arm 600 shown in the drawing is provided with a plurality of fingers 603 from the base 602, and is connected to the arm 610 via the wrist 604. Here, a portion of the root portion of the finger portion 603 is movable in the base 602, and the piezoelectric motor 1 is mounted in a state where the driving convex portion 114 is pressed against the root portion of the finger portion 603. Therefore, the finger 603 can be moved by the operation of the piezoelectric motor 1 to grip the object. Further, in the portion of the wrist 604, the piezoelectric motor 1 is mounted in a state where the driving convex portion 114 is pressed against the end surface of the wrist 604. Therefore, the entire base 602 can be rotated by operating the piezoelectric motor 1.

FIG. 15 is an explanatory view showing a one-arm robot 650 including a robot arm 600 (hand). As shown, the robot 650 has an arm 610 (wrist) that includes a plurality of link portions 612 (link members) and is connected between the link portions 612 in a bendable state. Joint portion 620. Further, the robot arm 600 is coupled to the front end of the arm 610. Further, the piezoelectric motor 1 is built in the joint portion 620. Therefore, each joint can be made by operating the piezoelectric motor 1 The portion 620 is bent at an arbitrary angle.

FIG. 16 is an explanatory diagram illustrating a multi-arm robot 660 including a robot arm 600. As shown, the robot 660 has a plurality of (two in the illustrated example) arms 610 including a plurality of link portions 612 and connecting the link portions 612 in a bendable state. Joint joint 620. A machine arm 600, or a tool 601 (hand) is attached to the front end of the arm 610. Further, a plurality of cameras 663 are mounted on the head unit 662, and a control unit 666 that controls the overall operation is mounted inside the main body unit 664. Further, it can be transported by the casters 668 provided on the bottom surface of the main body portion 664. In the robot 660, the piezoelectric motor 1 is also incorporated in the joint portion 620. Therefore, each joint portion 620 can be bent at an arbitrary angle by operating the piezoelectric motor 1.

Fig. 17 is a perspective view showing an electronic component inspection device 700 constructed by incorporating the piezoelectric motors 1x, 1y, and 1θ of the present embodiment shown in Fig. 18. The illustrated electronic component inspection device 700 generally includes a base 710 and a support table 730 that is erected on the side of the base 710. On the upper surface of the base 710, an upstream side mounting table 712u on which the electronic component 3 to be inspected is placed and transported, and a downstream side mounting table 712d on which the inspected electronic component 3 is placed are placed. Further, between the upstream side mounting table 712u and the downstream side mounting table 712d, an imaging device 714 for checking the posture of the electronic component 3 and an inspection table 716 (inspection portion) for mounting the electronic component 3 to check electrical characteristics are provided. Further, as a representative of the electronic component 3, "semiconductor" or "semiconductor wafer", "CLD (Crystal LED Display)", or OLED (Organic light-Emitting Diode) can be cited. Display devices, crystal devices, various sensors, inkjet heads, and various MEMS (Micro Electro Mechanical Systems) devices.

Further, the support table 730 is provided with a Y mounting table 732 that is movable in a direction (Y direction) parallel to the upstream side mounting table 712u and the downstream side mounting table 712d of the base 710, and is oriented from the Y mounting table 732 toward the base station. A wrist 734 is extended in the direction of the 710 (X direction). Further, an X mounting table 736 movable in the X direction is provided on the side surface of the wrist portion 734. Moreover, placed on X The stage 736 is provided with an imaging camera 738 and a holding device 750 having a Z mounting table movable in the vertical direction (Z direction). Further, a grip portion 752 that holds the electronic component 3 is provided at the front end of the grip device 750. Further, a control device 718 for controlling the overall operation of the electronic component inspection device 700 is also provided on the front side of the base 710. Further, in the present embodiment, the Y mounting table 732, the wrist portion 734, the X mounting table 736, or the holding device 750 provided on the support table 730 corresponds to the "electronic component conveying device" of the present invention.

The electronic component inspection apparatus 700 having the above configuration performs inspection of the electronic component 3 as follows. First, the electronic component 3 to be inspected is placed on the upstream side mounting table 712u and moved to the vicinity of the inspection table 716. Next, the Y stage 732 and the X stage 736 are moved, and the holding device 750 is moved to a position directly above the electronic component 3 placed on the upstream stage 712u. At this time, the position of the electronic component 3 can be confirmed using the camera camera 738. Then, when the holding device 750 is lowered by using the Z mounting table built in the holding device 750, and the electronic component 3 is held by the grip portion 752, the holding device 750 is directly moved to the imaging device 714, and the imaging is performed. The device 714 confirms the posture of the electronic component 3. Then, the posture of the electronic component 3 is adjusted using the fine adjustment mechanism built in the holding device 750. Then, after the holding device 750 is moved to the inspection table 716, the Z stage placed in the holding device 750 is moved to place the electronic component 3 on the inspection table 716. Since the posture of the electronic component 3 is adjusted using the fine adjustment mechanism in the holding device 750, the electronic component 3 can be placed at the correct position of the inspection table 716. Then, after the inspection of the electrical characteristics of the electronic component 3 is completed using the inspection table 716, after the electronic component 3 is picked up from the inspection table 716, the Y mounting table 732 and the X mounting table 736 are moved to move the holding device 750 downstream. The side mount 712d is placed on the downstream stage mounting table 712d. Thereafter, the moving downstream side mounting table 712d transports the electronic component 3 after the inspection is completed to a specific position.

FIG. 18 is an explanatory view of a fine adjustment mechanism built in the holding device 750. As shown in the drawing, the holding device 750 is provided with a rotating shaft 754 connected to the grip portion 752, a fine adjustment plate 756 to which the rotating shaft 754 is rotatably mounted, and the like. Moreover, the micro adjustment plate 756 can be one side It moves in the X direction and the Y direction while being guided by a guide mechanism (not shown).

Here, as shown by hatching in FIG. 18, the piezoelectric motor 1θ for the rotational direction is mounted on the end surface of the rotating shaft 754, and the driving convex portion (not shown) of the piezoelectric motor 1θ is pressed against the rotating shaft. The end face of 754. Therefore, by operating the piezoelectric motor 1θ, the rotating shaft 754 (and the grip portion 752) can be accurately rotated by an arbitrary angle around the θ direction. Further, the piezoelectric motor 1x for the X direction and the piezoelectric motor 1y for the Y direction are provided toward the fine adjustment plate 756, and the drive projections (not shown) are pressed against the surface of the fine adjustment plate 756. Therefore, by operating the piezoelectric motor 1x, the fine adjustment plate 756 (and the grip portion 752) can be accurately moved by an arbitrary distance in the X direction, and similarly, the piezoelectric motor 1y is operated. The fine adjustment plate 756 (and the grip portion 752) can be accurately moved by an arbitrary distance in the Y direction. Therefore, the electronic component inspection device 700 of FIG. 17 can finely adjust the posture of the electronic component 3 held by the grip portion 752 by operating the piezoelectric motor 1θ, the piezoelectric motor 1x, and the piezoelectric motor 1y.

Fig. 19 is an explanatory view showing a liquid supply pump 800 constructed by incorporating the piezoelectric motor 1 of the present embodiment. Fig. 19(a) shows a plan view of the liquid feeding pump 800 in a plan view, and Fig. 19(b) shows a cross-sectional view of the side liquid feeding pump 800. As shown in the figure, the liquid supply pump 800 is rotatably provided with a disk-shaped rotor 804 (moving portion) in a rectangular casing 802, and a liquid such as a chemical liquid is sandwiched between the casing 802 and the rotor 804. A tube 806 (liquid tube) that circulates inside. Further, a part of the tube 806 is in a state of being blocked by the ball 808 (blocking portion) provided in the rotor 804. Therefore, if the rotor 804 rotates, the ball 808 moves to the position where the tubular body 806 is swollen, so that the liquid of the tubular body 806 is transported. Further, when the driving convex portion 114 of the piezoelectric motor 1 of the present embodiment is provided in a state of being pressed against the side surface of the rotor 804, the rotor 804 can be driven. According to this, it is possible to accurately transport a very small amount of liquid, and a small liquid supply pump 800 can be realized.

Fig. 20 is a perspective view showing a printing apparatus 850 incorporating the piezoelectric motors 1c, 1m, and 1s of the present embodiment. The printing apparatus 850 shown is a so-called inkjet printer that ejects ink on the surface of the printing medium 2 to print an image. The printing device 850 has a substantially box-shaped appearance shape and is in front of A paper feed tray 851, a discharge port 852, or a plurality of operation buttons 855 are disposed substantially at the center. Further, a paper holder 853 for arranging the printing medium 2 (roller paper 854) wound in a roll shape is provided on the back side. When the roll paper 854 is placed on the paper holder 853 and the operation button 855 is operated, the roll paper 854 placed on the paper holder 853 is sucked, thereby printing an image on the surface of the print medium 2 inside the printing apparatus 850. Further, the roll paper 854 is discharged from the discharge port 852 after being cut by the following cutting mechanism 880 mounted inside the printing apparatus 850.

Inside the printing apparatus 850, a print head 870 that reciprocates in the main scanning direction on the printing medium 2, and a guide rail 860 that guides the movement of the print head 870 in the main scanning direction are provided. Further, the illustrated print head 870 includes a printing portion 872 for ejecting ink on the printing medium 2, a scanning portion 874 for scanning the printing head 870 in the main scanning direction, and the like. A plurality of ejection nozzles are provided on the bottom surface side (the side facing the printing medium 2) of the printing portion 872, and ink can be ejected from the ejection nozzle toward the printing medium 2. Further, piezoelectric motors 1m and 1s are mounted on the scanning unit 874. The convex portion (not shown) of the piezoelectric motor 1m is pressed against the guide rail 860. Therefore, by operating the piezoelectric motor 1m, the print head 870 can be moved in the main scanning direction. Further, the driving convex portion 114 of the piezoelectric motor 1s is pressed against the printing portion 872. Therefore, by operating the piezoelectric motor 1s, the bottom surface side of the printing portion 872 can be made close to the printing medium 2 or away from the printing medium 2. Further, a cutting mechanism 880 for cutting the roll paper 854 is also mounted on the printing apparatus 850. The cutting mechanism 880 includes a cutter holder 884 having a paper cutter 886 at its tip end, and a guide shaft 882 extending through the cutter holder 884 and extending in the main scanning direction. The piezoelectric motor 1c is mounted in the cutter holder 884, and a convex portion (not shown) of the piezoelectric motor 1c is pressed against the guide shaft 882. Therefore, when the piezoelectric motor 1c is operated, the cutter holder 884 moves in the main scanning direction along the guide shaft 882, and the paper cutter 886 cuts the roller paper 854. Further, in order to perform paper feed of the printing medium 2, the piezoelectric motor 1 can also be used.

Fig. 21 is an explanatory view showing an internal structure of an electronic clock 900 incorporating the piezoelectric motor 1 of the present embodiment. 21 is shown on the opposite side of the electronic clock 900 from the time display side. (back cover side) A top view for observation. The inside of the electronic clock 900 illustrated in FIG. 21 includes a disk-shaped rotating circular plate 902, and a gear train 904 for transmitting the rotation of the rotating circular plate 902 to a pointer (not shown) for displaying the time, for driving the rotating circular plate. A piezoelectric motor 1 of 902, a power supply unit 906, a crystal wafer 908, and an IC (integrated circuit) 910. Further, the power supply unit 906, the crystal wafer 908, and the IC 910 are mounted on a circuit board (not shown). The gear train 904 is composed of a plurality of gears or a ratchet (not shown). Further, in order to avoid complication of the illustration, in Fig. 21, the line connecting the tops of the gears is indicated by a thin single-point chain line, and the line connecting the tooth roots is indicated by a thick solid line. Therefore, the double circle formed by the thicker solid line and the thinner single-point chain line represents the gear. Further, the single-dot chain line indicating the thinness of the tooth tip does not indicate the entire circumference, but only the periphery of the portion that meshes with the other gears.

A smaller gear 902g is coaxially disposed on the rotating circular plate 902, and the gear 902g is meshed with the gear train 904. Therefore, the rotating side of the rotating circular plate 902 is transmitted in the gear train 904 while being decelerated at a specific ratio. Then, the rotation of the gear is transmitted to the pointer indicating the time to display the time. Further, when the driving convex portion 114 of the piezoelectric motor 1 of the present embodiment is placed in a state of being pressed against the side surface of the rotating circular plate 902, the rotating circular plate 902 can be rotated.

Fig. 22 is an explanatory view showing a projection apparatus 950 incorporating the piezoelectric motor 1 of the present embodiment. As shown, the projection device 950 includes a projection unit 952 including an optical lens, and displays an image by projecting light from a built-in light source (not shown). Further, the piezoelectric motor 1 of the present embodiment can also be used to drive the adjustment mechanism 954 (adjustment portion) for aligning the focus of the optical lens included in the projection portion 952. The positional resolution of the piezoelectric motor 1 is high, so that subtle focus can be achieved. Further, the optical lens of the projection portion 952 is covered by the lens cover 956 during the period when the light from the light source is not projected, thereby preventing damage to the optical lens. The piezoelectric motor 1 of the present embodiment can also be used in order to avoid opening and closing the lens cover 956.

As described above, the piezoelectric motor driven by the driving voltage generating circuit of the present invention and the various devices in which the piezoelectric motor is mounted have been described. However, the present invention is not limited to the above-described implementation. Examples, variations, and application examples can be implemented in various aspects without departing from the spirit and scope of the invention.

Claims (10)

A robot arm comprising a plurality of fingers and holding an object, comprising: a base body having a movable finger portion; and a driving device for moving the finger portion relative to the base body And the driving device includes: a vibrating body formed of a piezoelectric material and having a convex portion pressed against the object; and a voltage waveform output portion whose output repeats the first voltage and is higher than the above a voltage waveform of a second voltage of the voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and including a coil and a capacitor; and the voltage waveform is more resonant than the resonant period of the vibrating body A voltage waveform in which the first voltage and the second voltage are repeated and the modulation component of the resonant frequency of the vibrating body is modulated by a pulse width is repeated in a short period. The robot arm of claim 1, wherein the voltage waveform output unit receives a pulse signal having a voltage amplitude smaller than the voltage waveform, and outputs a pulse signal to amplify a voltage between the first voltage and the second voltage. The above voltage waveform is generated. The robot arm of claim 1, wherein the modulation component is a sine wave of the resonance frequency of the vibrating body. The robot arm of claim 1, wherein the voltage waveform repeats the waveforms of the first voltage and the second voltage in a period of one-seventh or less of the resonance period. A robot comprising: a wrist portion provided with a rotatable joint portion; a hand portion disposed on the wrist portion; and a body portion provided with the wrist portion; the robot characterized by comprising: being disposed on the joint portion and bending or rotating a driving device for driving the joint portion; the driving device includes: a vibrating body formed of a piezoelectric material and having a convex portion pressed against the object; and a voltage waveform output portion whose output repeats the first voltage at a constant period And a voltage waveform of a second voltage higher than the first voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and including a coil and a capacitor; and the voltage waveform is higher than the vibration The cycle in which the resonance period of the body is shorter is repeated. The voltage waveform of the first voltage and the second voltage and the modulation component of the resonant frequency of the vibrating body is modulated by the pulse width. The robot according to claim 5, wherein the voltage waveform output unit receives a pulse signal having a voltage amplitude smaller than the voltage waveform, and outputs a pulse signal generated by amplifying the voltage between the first voltage and the second voltage. The above voltage waveform. An electronic component transporting apparatus comprising: a grip portion that holds an electronic component; and a driving device that drives the grip portion that holds the electronic component; the electronic component transport device is characterized in that the driving device includes a vibrating body formed of a piezoelectric material and having a convex portion pressed against the grip portion; a voltage waveform output unit that outputs a voltage waveform in which the first voltage and the second voltage higher than the first voltage are repeated in a predetermined cycle; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and And including the coil and the capacitor; wherein the voltage waveform is a voltage that is modulated by a pulse width modulation of the first voltage and the second voltage in a period shorter than a resonance period of the vibrating body, and a modulation component of a resonant frequency of the vibrating body Waveform. An electronic component inspection apparatus comprising: a grip portion that holds an electronic component; a driving device that drives the grip portion that holds the electronic component; and an inspection portion that inspects the electronic component; the electronic component inspection The device is characterized in that the driving device includes a vibrating body formed of a piezoelectric material and having a convex portion pressed against the grip portion, and a voltage waveform output portion whose output repeats the first voltage with a certain period and a voltage waveform higher than a second voltage of the first voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, including a coil and a capacitor; and the voltage waveform is higher than the vibrating body The period in which the resonance period is shorter is a voltage waveform in which the first voltage and the second voltage are repeated, and the modulation component of the resonance frequency of the vibrating body is pulse width modulated. A driving device comprising: a vibrating body formed of a piezoelectric material and having a convex portion pressed against the object; and a voltage waveform output portion whose output repeats the first voltage at a certain period and higher than the above a voltage waveform of a second voltage of the first voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and including a coil and a capacitor; wherein the driving device is characterized in that the voltage waveform is compared The period in which the resonant period of the vibrating body is shorter is a voltage waveform in which the first voltage and the second voltage are repeated, and the modulation component of the resonant frequency of the vibrating body is pulse width modulated. A driving circuit comprising a piezoelectric motor including a vibrating body formed of a piezoelectric material, comprising: a voltage waveform output unit that outputs a first voltage and a higher voltage than the first voltage in a predetermined cycle a voltage waveform of the second voltage; and an LC circuit unit interposed between the voltage waveform output unit and the vibrating body, and including a coil and a capacitor; and the voltage waveform is shorter than a resonance period of the vibrating body The voltage waveform in which the modulation voltage of the resonant frequency of the vibrating body is modulated by the pulse width is repeated in a period in which the first voltage and the second voltage are repeated.