JP3059043B2 - Ultrasonic vibrator, ultrasonic motor and device equipped with ultrasonic motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention, by vibrating the elastic body as an ultrasonic vibrator Ri by the supplying electrical energy to the piezoelectric element, cormorants line movement of the pressed mating member to the vibrator ultra < br /> wave oscillator, particularly suitable ultrasonic transducer in the ultrasonic motor to cod also a rotational movement of the mating member, an ultrasonic motor and an ultrasonic motor
The present invention relates to an apparatus provided with data .

[0002]

2. Description of the Related Art FIG. 8 is an exploded perspective view of a bar-shaped ultrasonic transducer according to the prior art.

A bar-shaped ultrasonic vibrator is composed of a disk-shaped piezoelectric element 1, an upper vibrator 2, a lower vibrator 3, an electrode plate 19, and an insulating sheet 22 made of a resin material.
And fastening bolts 5 for fastening these.

[0004] Electrodes are provided on one end face and side faces of the piezoelectric element so as to divide the disk part into approximately four equal parts. The piezoelectric element 1 is polarized in the thickness direction for each electrode, and the electrodes at positions opposed to the central axis are polarized in opposite directions. A power supply lead wire is connected to each electrode on the side surface of the piezoelectric element by soldering. As shown in FIG. 9, the electrode 6A is an A phase electrode, the electrodes 6B1 and 6B2 are B phase electrodes, and the electrode 6S is a sensor phase electrode.

When a voltage is applied to the phase A of the piezoelectric element 1, a bending deformation occurs in the vibrator. If the voltage is AC voltage,
The vibrator generates bending vibration. When a voltage is similarly applied to the phase B, bending vibration occurs in a direction including the central axis and substantially perpendicular to the direction of vibration of the phase A. The applied voltage to phase B
When an appropriate time phase difference is given to the applied voltage to the phase, an arbitrary point of the vibrator generates an oscillation that draws an elliptical trajectory.

When a moving body (not shown) is brought into pressure contact with an arbitrary point of the vibrator, for example, the upper end surface of the upper vibrating body, which causes such vibration, the moving body is moved by the elliptical motion of the vibrator. Is given. By selecting a cylindrical member for the moving body and making the center axis of the moving body rotatably supported, the moving body is given a rotational motion, and an ultrasonic motor is configured. In this ultrasonic motor, a moving body is driven by applying an AC voltage to the piezoelectric element and generating a bending vibration at the AC frequency in the vibrator. Normally, the vicinity of the resonance frequency of the natural mode of the vibrator is selected as the AC frequency. However, since the resonance frequency of the vibrator varies from several hundreds to several thousand Hz due to variations among individuals, environmental temperature, load applied to the vibrator, etc., the input voltage is required to drive the vibrator efficiently and stably. It is necessary to control the AC frequency of the sensor, and a sensing means for monitoring the vibration state of the vibrator is required.

[0007]

However, such a vibrator has the following problems.

The connection between the piezoelectric element and an external control circuit is made by a lead wire, and the lead wire is fixed to the piezoelectric element by soldering. In this method, the lead wire is likely to fall off due to a defect in soldering, and it is difficult to reach the solder melting temperature due to the propagation of heat to the piezoelectric element and the vibrating body. In addition, variations in the vibration characteristics of the vibrator due to the state of solder adhesion occur. Depolarization of the piezoelectric element may occur due to a rise in temperature of the piezoelectric element during soldering. Due to these problems, it has been difficult to form a vibrator stably and easily with the conventional technology.

Providing the sensing means for monitoring the vibration state of the vibrator separately from the vibrator main body causes an increase in the number of necessary parts, resulting in a complicated configuration and an increase in dimensions. In order to avoid this point, when a sensing area is provided on a piezoelectric element used for driving, connection to the outside must be performed by soldering as described above, which causes various problems. In addition, the sensing region formed in the piezoelectric element suppresses a decrease in the region used for driving, so that the sensing region formed in the piezoelectric element cannot be made large and the output signal thereof is small. Therefore, a configuration for accurately detecting the output signal of the sensing area is required.

[0010] It is therefore an object of the present invention is to solve the problems of the prior art described above, the ultrasonic transducer of novel structure that does not use lead wires to the electrical connection between the piezoelectric element and an external circuit,
An ultrasonic motor and an apparatus provided with the ultrasonic motor are provided . Also, even if the sensor area on the piezoelectric element is small, the output signal does not contain noise or the like, and an ultrasonic vibrator or an ultrasonic motor configured to perform highly accurate detection.
An object of the present invention is to provide an apparatus provided with a motor and an ultrasonic motor .

[0011]

Means for Solving the Problems Object of the Invention According to the Present Application
The configuration of the ultrasonic transducer that realizes
Elastic body formed and piezoelectric element held by the elastic body
And the elastic element is pressed against the piezoelectric element and
The piezoelectric element and the external circuit are
And a printed circuit board for connecting to a power supply.
Ultrasonic transducer, wherein on the piezoelectric element, the
For lead pattern of sensor electrode on printed circuit board
Provide an electrode non-formed part where no electrode is provided facing
It is a thing. In the above configuration, the piezoelectric element includes:
Structured as a stacked piezoelectric element with several piezoelectric element plates stacked
The multilayer piezoelectric element has a plurality of components on one side only.
At least one first piezoelectric element plate having split electrodes,
At least one second pressure plate having a full-surface electrode on only one side
A first piezoelectric element plate and the second piezoelectric element plate.
Alternately with the element plate with each electrode forming surface facing up
The piezoelectric element plates
The pole is shared with the electrode of the piezoelectric element plate just below it,
The printed circuit board is provided on the electrode forming surface of the first piezoelectric element plate.
Being press-contacted, the first piezoelectric element plate and the second
On the piezoelectric element plate, the sensor electrodes of the printed circuit board
Electrode without an electrode facing the lead pattern of
An extremely non-formed portion was provided . Realize the purpose of the invention according to the present application
The configuration of the ultrasonic motor that performs
A moving body that is frictionally driven by being pressed against the end face of an ultrasonic transducer
It has . The purpose of the invention of the present application
The configuration of the device provided with the ultrasonic motor to be described is as described above.
Driven by Moving Object in Ultrasonic Motor
It has a moving mechanism .

[0012]

【Example】

<Embodiment 1> FIG. 1 is an exploded perspective view of a rod-shaped ultrasonic transducer according to a first embodiment of the present invention. FIG. 2 is a plan view showing the electrode arrangement of the piezoelectric element used in this embodiment. FIG. 3 is a diagram showing the electrode configuration of the flexible printed circuit board 4 used in the bar-shaped ultrasonic transducer of this embodiment.

As shown in FIG. 1, the vibrator comprises two annular or perforated disk-shaped piezoelectric elements 1-1 and 1-2, an upper vibrator 2 and a lower vibrator 3, which are formed of a metal material. Printed circuit board 4 for connecting each electrode of the piezoelectric element to an external control circuit, and fastening bolt 5 for integrating them
It is composed of In this embodiment, two piezoelectric elements 1-1 and 1-2 are used, and a printed circuit board 4 is provided between the two piezoelectric elements.
Is sandwiched. These two piezoelectric elements have the same shape.

PZT was used as the material of the piezoelectric element, and a material which had been machined to have an inner diameter of 4 mm, an outer diameter of 8 mm, and a thickness of 0.4 mm after construction was used. As shown in FIGS. 1 and 2, electrodes 6-1 to 6-4 are arranged on the first surfaces of the piezoelectric elements 1-1 and 1-2 so as to divide the circumference of the piezoelectric element into approximately four equal parts. As shown in FIG. 2, these electrodes are
Are separated from each other by -1 to 104-4. Electrodes 6-1 and 6-5 which are separated from each other in the radial direction are formed in one area of the whole circumference divided into four. Piezoelectric element 1-
Although the common electrode 6G is disposed on almost the entire surface of the second surfaces 1 and 1-2, the electrode non-forming portion 104-5 is disposed at a position where the phase matches the electrode non-forming portion 104-1. Have been.

In the piezoelectric elements 1-1 and 1-2, the regions where the divided electrodes 6-1 to 6-5 are arranged are polarized in the thickness direction, and the electrode non-forming portions 104-1 are formed. ~ 1
04-5 is not polarized. Also, the split electrode 6
The regions where -1, 6-2, and 6-5 are arranged are polarized in the thickness direction with these electrodes at high potential, and the regions where electrodes 6-3 and 6-4 are arranged are those electrodes. Polarization is performed as a low potential, and in FIG. 2, respective potentials are indicated by (+) and (−).

As shown in FIG. 2, the piezoelectric elements 1-1 and 1
The polarization state of the LL cross section of -2 is the electrode 6-1 and the electrode 6-
Polarization is applied to a region sandwiched between the electrode 2 and the electrode 6G, but no polarization is applied to a region sandwiched between the electrode non-formed portions 104-1 and 104-5.

The printed circuit board 4 has a thickness of 25 μm on the base material.
m, a copper foil having a thickness of 35 μm is used as an electrode material, and a printed board material without an adhesive layer is used.
This is to prevent the attenuation of the vibrator from increasing due to the adhesive layer in the printed circuit board. As shown in FIG. 3, each electrode 6-of the piezoelectric element 1-1 is provided on the upper surface of the disk portion of the printed circuit board 4.
Electrodes 7A1, 7A2, 7B at positions corresponding to 1-6-5
1, 7B2, 7S are formed, and in a state where the vibrator is assembled, the electrode 7A1 on the printed circuit board 4 is the electrode 6-1 on the piezoelectric element 1-1, and the electrode 7A2 is the electrode 6-3.
The electrode 7B1 is connected to the electrode 6-2, and the electrode 7B2 is connected to the electrode 6-2.
4, the electrode 7S is pressed against the electrode 6-5. The electrodes 7A1 and 7A2 are connected to each other by a lead pattern 8-6 on the printed circuit board 4.

The electrodes 7A3, 7A4, 7B3, 7B4 are provided on the back surface of the disk portion of the printed circuit board 4 at positions corresponding to the electrodes 6-1 to 6-4 of the piezoelectric element 1-2 similarly to the back surface. Is formed and the ground electrode 7G is formed.
In the vibrator assembly state, the electrodes 7A3 and 6-2, 7A4 and 6-
4, 7B3 and 6-1 and 6-5 and 7B4 and 6-3 are pressed against each other. Also, the electrodes 7B3 and 7B4
Are connected by a lead pattern 8-7. The grounding electrode 7G is electrically grounded by contacting the fastening bolt 5 formed of a metal material. The electrode 7A1 is connected to the electrode 7A3 on the back side through a through hole 101, and similarly, 7A2 and 7A4, 7B1 and 7B3, and 7B2 and 7B4 are connected to each other through holes. The electrodes 6-1 and 6-3 of the piezoelectric element 1-1 and the electrodes 6-2 and 6-4 of the piezoelectric element 1-2 are A-phase electrodes. Similarly, the electrodes 6-2 and 6-4 of the piezoelectric element 1-1 and the electrodes 6-1 and 6-5 and 6-3 of the piezoelectric element 1-2 are B-phase electrodes.
The electrode 6-5 of the piezoelectric element 1-1 is a sensor electrode, that is, has an S phase.

A connection terminal 9 for connection to an external control circuit is provided on the printed circuit board 4. The electrode 7A1 is connected to the terminal 9A, the electrode 7B1 is connected to the terminal 9B, and the electrode 7G is connected to the terminal 9G. , Electrode 7S is terminal 9S
, Respectively.

The fastening bolt 5, the upper vibrating body 2 and the lower vibrating body 3 are made of a metal material, and have the same electric potential (ground). Also, the ground electrode 7G of the printed circuit board 4
Is grounded in close contact with the fastening bolt 5, and the electrodes 6-G of the piezoelectric elements 1-1 and 1-2 are in pressure contact with the upper vibrating body 2 and the lower vibrating body 3, respectively. It has the same potential as the electrode 7G. The piezoelectric elements 1-1 and 1-2 are connected to the piezoelectric elements 1-1 and 1-2 by applying a voltage to the connection terminals 9 of the printed circuit board 4 to which a GND potential is applied. Power is supplied.
By setting the connection terminal 9G to the GND potential and applying a voltage to the connection terminal 9A, the A phase of the piezoelectric element is driven. Similarly, the B phase is driven by applying a voltage to the connection terminal 9B.
Then, a sensor signal in which an S phase occurs is detected by the connection terminal 9S.

When a voltage is applied to the connection terminal 9A, the A phase of the piezoelectric element generates a strain, and the vibrator bends in the X direction shown in FIG. Similarly, when a voltage is applied to the B phase, it is bent in the Y direction substantially orthogonal to the X direction. When the applied voltage is an AC voltage and, for example, an AC frequency near the natural frequency of the bending vibration of the vibrator is selected, a periodic and stable bending vibration of the vibrator can be obtained. When an appropriate time phase difference is applied to the voltage applied to the phase A as the voltage applied to the phase B, an arbitrary point of the vibrator vibrates so that the trajectory draws an ellipse.
When a moving body (not shown) is brought into pressure contact with an arbitrary point of the vibrator vibrating in this manner, for example, the upper end face of the upper vibrating body, the moving body is moved by the elliptic motion of the surface particles of the vibrator. Empowered.

The electrode 6-5 of the piezoelectric element is distorted by bending deformation of the vibrator, and generates electric charge by the piezoelectric effect. By detecting this charge from the connection terminal 9S, the vibration state of the vibrator is monitored. The electrode 6-5 is arranged at a position shifted from the A-phase piezoelectric element by 0 rad. When the vibrator is assembled, the piezoelectric element 1-1 and the printed circuit board 4 are in close contact with each other.
Contacts the electrode non-formed portion 104-1 of the piezoelectric element 1-1. The piezoelectric element 1 to which this lead pattern 8-4 contacts
If the region 1 is polarized, electric charges are generated similarly to the region having the electrode 6, which is included in the signal detected from the connection terminal 9S, and the positional phase of the S phase is shifted. This makes accurate monitoring of the vibration state impossible. The piezoelectric element 1-1 has a lead pattern 8-
By setting both surfaces of the region in contact with 4 with no electrode formed portion, polarization due to a leaked electric field is prevented, and detection of a sensor signal without phase shift is performed.

The relationship between the applied voltage of the A-phase piezoelectric element and the phase difference between the output signals of the sensor phase with respect to the frequency at this time (hereinafter θA
-S), and the magnitude of the output signal of the sensor phase (V
FIG. 4 shows the relationship s). When the vibrator is driven in the bending primary vibration mode, the phase difference θA−S at the resonance frequency Fr
Is CW (clockwise), CCW (counterclockwise)
Both become (90π / 180) rad, and gradually shift at frequencies higher than the resonance frequency. The magnitude (Vs) of the output signal has a maximum value near the resonance frequency, and gradually decreases at frequencies higher than the resonance frequency. Therefore,
By detecting the phase difference θA-S and the magnitude of the output signal when vibration is applied, the relationship between the input frequency and the resonance frequency of the vibrator can be monitored, and the vibrator can be driven stably.

FIG. 10 is a longitudinal sectional view of a rod-shaped ultrasonic motor using the rod-shaped ultrasonic transducer of the present invention. The fastening bolt 5 of the vibrator has a small-diameter support 5p at the tip, and this support 5
The motor itself can be fixed by the fixing member 15 fixed to the tip of p, and the function of supporting the rotation of the moving body is also used. The moving body 18 comes into contact with the distal end surface of the upper elastic body 2, and pressurization is applied from the fixed member 15 to the spring case 1 provided inside the moving body 18 via the bearing member 13 and the gear 14.
7 is provided by pressing the coil spring 16.

FIG. 11 shows an optical device using the rod-shaped ultrasonic motor of this embodiment .

The gear 14 integrated with the rod-shaped ultrasonic motor meshes with the input gear GI of the gear transmission mechanism G, and the output gear G0 is a gear formed on the lens holding member H holding the lens L1. It is engaged with HI. The lens holding member H is helicoidally coupled to the fixed barrel K, and is driven to rotate by a driving force of an ultrasonic motor via a gear transmission mechanism G to perform focusing.

Embodiment 2 FIG. 5 shows the configuration of a laminated piezoelectric element used in an ultrasonic transducer according to a second embodiment of the present invention. FIG. 6 shows the polarization state of the laminated piezoelectric element. FIG. 7 shows a flexible printed circuit board used in this embodiment. In this embodiment, a single-phase driving phase is provided in the laminated piezoelectric element. However, two-phase driving phases can be formed by changing the configurations of the laminated piezoelectric element and the flexible printed circuit board.

The laminated piezoelectric element 10 is formed by laminating a plurality of piezoelectric element plates in which ceramic powder which has been calcined in advance and then pulverized is formed into a sheet. Multilayer piezoelectric element 1 of the present embodiment
Reference numeral 0 denotes five piezoelectric element plates 100-1 to 100-5, each of which has a diameter of 8 mm, a thickness of each layer of 0.1 mm, and a total length of 0.5 mm. An electrode film is formed on one or both sides of each piezoelectric element plate and
Conduction holes (holes covered with a metal film for electrodes) 101a to
101c is provided at the same position.

FIG. 5 shows each of the piezoelectric element plates 100-1 to 100-100.
The surface of Table -5 and the back surface of the piezoelectric element plate 100-5 are shown.

On the front surface of the first piezoelectric element plate 100-1, an annular electrode-free portion 104- is formed along the outer periphery of the center hole.
14 and the electrode non-forming portion 104-14.
Electrode non-forming portions 104 having radial portions connected to
-11 and 104-12, two divided electrodes 30a
1, 30b1 are formed, and an arc-shaped sensor split electrode 30s is formed inside the arc-shaped electrode-free portion inside the split electrode 30a1.

On the front surface of the second piezoelectric element plate 100-2, an annular electrode non-formed portion 104-14 is provided along the outer periphery of the center hole, and the electrode non-formed portion 104 of the piezoelectric element plate 100-1 is formed. No electrode forming portion 104-13 having the same shape as -11
Is provided at the same position as the portion 104-11, and the other surface is covered with an electrode film as the entire surface electrode 31-1. In addition, two of the three through-holes formed through the two through-holes 1
A ring-shaped electrode non-formed portion is provided around 01a and 101b.

On the front surface of the third piezoelectric element plate 100-3, an annular electrode non-forming portion 104-1 along the outer periphery of the center hole is provided.
4 and two radial electrode-free portions 104-15 and 104-15.
04-16, and two divided electrodes 30a2 and 30b2 separated by the electrode non-formed portions 104-15 and 104-16 are formed.

On the front surface of the fourth piezoelectric element plate 100-4, an annular electrode-free portion 104-14 is provided along the outer periphery of the center hole, and the entire surface of the electrode 3 is entirely covered with an electrode film.
1-2 are formed, and two conduction holes 101a and 101b are formed.
Is also provided with an annular electrode non-formed portion.

On the front surface of the fifth piezoelectric element plate 100-5, an annular electrode non-forming portion 104-1 along the outer periphery of the center hole is provided.
4 and two radial electrode-free portions 104-17 and 104-17.
04-18, and the electrode non-forming portion 1
Two divided electrodes 30a3 and 30b3 separated by 04-17 and 104-18 are formed. Also,
Only one conduction hole 101c is provided in the electrode non-formed portion 104-18.
Is open. On the other hand, on the back surface of the piezoelectric element plate 100-5, an annular electrode non-formed portion 104-14 is provided along the center hole, and a conduction hole 101c is opened.
1-3 are formed.

Each of the piezoelectric element plates 100-1 to 100 as described above
The laminated piezoelectric element 10 is formed by superimposing 0-5 with their front surfaces facing up so that the positions of the electrode non-formed portions and the conductive holes coincide with each other.

The laminated piezoelectric element 1 thus formed
6 is connected by using two high resistances as shown in FIG. 6A so that a voltage can be divided, and a contact pin is brought into contact with each of the divided electrodes 30a1, 30b1, and 30s on the upper end surface of the laminated piezoelectric element. By applying a DC voltage from a DC power supply, the laminated piezoelectric element 10 is polarized in the direction of the arrow shown in FIG. As a result, the region where the divided electrode 30a1 is disposed and the region where the divided electrode 30b1 is disposed are polarized in opposite directions, and can be used as, for example, an A-phase driving piezoelectric element in the ultrasonic transducer. The piezoelectric element plate 100-
The split electrode 30s provided in 1 becomes a sensor phase electrode.

A printed circuit board 20 shown in FIG. 7 is used for making an electrical connection to the outside when the laminated piezoelectric element 10 is incorporated in a vibrator. The printed circuit board 20 shown in FIG. 7 includes an annular disk portion that is in pressure contact with the laminated piezoelectric element 10 to make electrical connection and a portion that makes connection to the outside. A substrate electrode 7A in contact with the divided electrodes 30a1 and 30b1 of the piezoelectric element plate 100-1 and a substrate electrode 7S in contact with the divided electrode 30s are formed in the annular disk portion of the printed circuit board 20,
Each board electrode is connected to a connection terminal by a lead pattern on the printed board 20. Substrate electrode 7S and connection terminal 9S
Since the lead pattern 8S connecting the electrodes makes pressure contact with the electrode non-formed portion 104-11 of the laminated piezoelectric element 10 in the annular disk portion, if this region is polarized, electric charges are generated due to distortion of the piezoelectric element. Thus, a desired sensor signal cannot be obtained by the connection terminal 9S. In consideration of this point, the laminated piezoelectric element 10 has the electrode non-forming portions 104-1 on both sides of the area of the piezoelectric element plate 100-1 where the lead pattern 8S contacts.
1, 104-13 are formed to prevent polarization due to a leakage electric field and generate a desired sensor signal.

Note that the laminated piezoelectric element 10 shown in this embodiment is
Although the ultrasonic transducer using the device is different from the conventional example shown in FIG. 8 in that a printed circuit board is used for the arrangement of sensor phases and connection to the outside, the driving method is the same as that of the conventional example. is there.

[0039]

As described above, in the ultrasonic transducer according to the present invention, a printed circuit board is used as a connecting means for electrically connecting the piezoelectric element to an external circuit and a power supply, and the printed circuit board is connected to the piezoelectric element. Because it is configured to hold the piezoelectric element together with the piezoelectric element in the state of being in close contact with the elastic body of the vibrator,
This eliminates the need for soldering lead wires, and avoids various problems associated with soldering lead wires. As a result, it is possible to efficiently manufacture ultrasonic transducers with more stable quality than before. It became possible to do. Further, in the ultrasonic transducer of the present invention, since the sensor lead pattern on the printed circuit board comes into contact with the electrode non-formation part of the piezoelectric element, there is no possibility that noise may enter the sensor signal, so that the detection accuracy is high. That is, even if the area of the sensor phase on the piezoelectric element is small, highly accurate detection can be performed.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a rod-shaped ultrasonic transducer according to a first embodiment of the present invention.

FIG. 2 shows a front surface (a), a back surface (b), and a cross section (c) of a piezoelectric element 1-1 used in the rod-shaped ultrasonic transducer shown in FIG.
FIG.

FIG. 3 is a diagram showing a front surface and a back surface of a flexible printed circuit board used for the rod-shaped ultrasonic transducer shown in FIG. 1;

FIG. 4 is a diagram showing sensor phase characteristics when a rod-shaped ultrasonic transducer is driven.

FIG. 5 is a diagram showing a configuration of a laminated piezoelectric element used in a second embodiment of the present invention.

6 is a diagram showing a polarization method (a) and a polarization state (b) of the laminated piezoelectric element shown in FIG.

FIG. 7 is a plan view of a flexible printed circuit board used in a second embodiment.

FIG. 8 is an exploded perspective view of a conventional bar-shaped ultrasonic transducer.

FIG. 9 is a view showing a conventional piezoelectric element.

FIG. 10 is a longitudinal sectional view of a rod-shaped ultrasonic motor according to the present invention.

11 is a longitudinal sectional view of a lens barrel incorporating a lens drive mechanism using the rod-shaped ultrasonic motor of FIG. 10 as a drive source.

[Explanation of symbols]

1-1, 1-2 Piezoelectric element 2 Upper vibrator 3 Lower vibrator 4 Flexible printed circuit board 5 Fastening bolts 6-1 to 6-5, 6G Electrodes 7A, 7S, 7A1, 7A2, 7B1, 7B2, 7A
3, 7A4, 7B3, 7G, 7B4: substrate electrode 8-1 to 8-7: lead pattern 9A, 9B, 9
S, 9G connection terminal 10 laminated piezoelectric element 13 bearing member 14 gear 15 fixing member 16 coil spring 17 spring case 18 rotor 19 electrode plate 20 flexible printed circuit board 22 insulating sheet 100-1 to 100- 5. Piezoelectric element plates 101, 101a to 101c: Through holes or conduction holes 104-1 to 104-5, 104-11 to 104-18
... electrode non-forming portions 30a1, 301b1, 30s, 30a2, 30a3
30b3, 31-1, 31-2, 31-3 ... electrodes

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H02N 2/00

Claims (4)

(57) [Claims] And 1. A resilient body forming the vibration Doko body portion, and a piezoelectric element which is clamp held the elastic body, is nipping held with the piezoelectric element to the elastic body while being pressed against the piezoelectric element an ultrasonic vibrator having a printed circuit board for connecting the piezoelectric element and an external circuit and a power supply, a though, wherein the on the piezoelectric element, a sensor on the printed circuit board
The electrode is provided opposite to the electrode lead pattern.
Ultrasonic transducer, characterized in that a free non-electrode portion. 2. The piezoelectric element according to claim 1, wherein the piezoelectric element is a laminated piezoelectric element in which several piezoelectric element plates are laminated, and the laminated piezoelectric element has at least one split electrode having a plurality of divided electrodes only on one surface. A first piezoelectric element plate, at least one second piezoelectric element plate having an entire surface electrode only on one side,
The first piezoelectric element plate and the second piezoelectric element plate are alternately overlapped with their respective electrode-forming surfaces facing upward, and the electrodes of each piezoelectric element plate are directly below the piezoelectric element. has become electrode shared plate, the printed circuit board is pressed against the electrodes forming surface of said first piezoelectric element plate Tei
On the first piezoelectric element plate and the second piezoelectric element plate
Is the lead pattern of the sensor electrode of the printed circuit board.
Electrode-free part where no electrode is provided facing the electrode
The ultrasound transducer of claim 1, characterized in that provided. Wherein the ultrasonic motor, characterized in that it has a claim 1 or 2 is pressed against the end surface of the ultrasonic transducers according to the friction driven movable body. 4. Contact ultrasonic motor according to claim 3
Equipped with a driving mechanism driven by a moving body
A device equipped with an ultrasonic motor .